i hereby declare that the work contained in this thesis

I hereby declare that the work contained in this thesis was carried out by myself during the period 1993-1996. The work contained in this thesis has not been submitted for any other degree or diploma.

ACKNOWLEDGEMENTS

I would like to thank Professor Brian Johnson for his unbridled enthusiasm and knowledge of the material contained in this work. Special thanks to Dr Philip Bailey for taking over my supervision in the final year, and for his excellent proof reading of this thesis. Thanks to Zeneca in Grangemouth, particularly Dr Nick Evens, for their financial support. Thanks also to Dr Simon Parsons for the crystallographic work contained in this thesis.

Thanks to the many people I have shared a lab with over the years: Ruth M., Ali, Scott, Jane, Gideon, Ruth P., Ken, Nick, and Alan, and also to the many other people in the group, and at Edinburgh, who made my time there so enjoyable. Thanks also to the technicians responsible for all the NMR and mass spectroscopy data included in this thesis.

Special thanks to my parents without whom this thesis would not have been possible. And finally to Lesley, for all her support and love over the years.

List Of Compounds And Numbers

1 { (bpy)Pd(C6H1000CH3)) (OTf) 2 { (bpy)Pd(C6H8COCH3) } (OTf) 3 { (bpy)Pd(C6H8COCH3) ) (OTf) 4 { (bpy)Pd(C6H 12COCH3) } (OTf) 5 { (bpy)Pd(C6H6COCH3) } (OTI) 6 {(bpy)Pd(C 6H5FCOCH3)}(OTf) 7 {(bpy)Pd(C 6H5BrCOCH3) } (OTt) 8 {(bpy)Pd(C 8H8COCH3)} (OTt) 9 { (bpy)Pd(C6H5CH3COCH3) } (OTt) 10 { (bpy)Pd(C 6H4(OH)2COCH3) } (OTt) 11 (tmeda)Pd(Ph) 2 12 0s3(CO)12 13 0s3(CO) io(MeCN)2' 14 0s3(C0)9(p.-H)2(C6H3F) 15 Os3(C0)9(t-H)2(C6H3C1) 16 0s3(C0)io(.i-Br)2 17 0s3(C0)9(t-H)2(C6H3CH3) 18 0s3(CO)9Q.x-H)2 {ortho-C6H2(CH3)3 } 19 Os3(CO)9(t-H)2 {meta-C 6H2(CH3)2 } 20 Os3(CO)9(j.t-H)2 {para-C 6H2(CH3)2) 21 0s3(C0)9(p-H)2 { C 6H3C(CH3)CH2) } 22 0s3 (C0)9Q.-H)2 { C6H3C(CH3)CH2) } 23 0s3(C0)9(j.t-H)2(C6H3CHCH2) 24 0s3(C0)9Qt-H)2 { C6H2(C(CH3)CH2)2) 25 Os3 (C0)9(t-H)2{ C 6H3F(COMe) } 26 Os3(C0)9(t-H)2 { C 6H3C1(COMe) } 27 0s3(CO)9(t-H)2 { C6H3CH3(COMe)) 28 0s3(CO)9(p-H)2 { ortho-C6H(CH3)2(COMe)) 29 0s3(CO)9Q.t-H)2 {meta-C 6H(CH3)2(COMC) } 30 Os3 (CO)8(.t-H)(CH2CHCHCH3)(C6H3F) 31 0s3(CO)8(p.-H)2(CH3HCCH3)(C6H3F)

Contents

1 CHAPTER ONE- INTRODUCTION

1 1 Friedel-Crafts Reactions

1 1.1 Introduction

2 1.2 Historical

4 1.3 Aromatic Ketone Synthesis

4 1.3.1 Introduction

5 1.3.2 Mechanism

6 1.3.3 Ratios and Addition Sequences

7 1.3.4 Solvents

8 1.3.5 Catalysts

15 1.3.6 Acyl Component

19 1.3.7 Houben-Hoesch Reaction

21 1.3.8 Fries Rearrangement

23 1.4 Conclusion

24 2 Cluster Chemistry

24 2.1 Introduction

24 2.2 The Surface Cluster Analogy

28 2.2.1 Chemisorption of Ethylene on a Pt(1 11) Surface

29 2.2.2 CO-adsorption of Benzene and CO on Rh(1 11)

31 2.3 Trinuclear Cluster Arene Chemistry

31 2.3.1 Introduction

32 2.3.2 Structures and Bonding Modes

33 2.3.3 Synthesis

37 2.3.4 Reactions

40 2.3.5 Conclusion

41 3 References

49 CHAPTER TWO- PALLADIUM COMPLEXES AS ACYLATION

CATALYSTS.

49 2.1 Introduction

49 2.1.1 Palladium Complexes and their use in Synthesising

CO/alkene Co-Polymers

56 2.1.2 Industrial Background

60 2.2 Reactions of(bpy)Pd(COMe)(I) with Cyclic Alkenes and Diene

62 2.3 Reactions of(bpy)Pd(COMe(I) with Arenes

64 2.4 Reaction of(tmeda)PdC1 2 with Phenyl Lithium

67 2.5 Conclusion

68 2.6 References

69 CHAPTER THREE- SYNTHESIS OF ARYNE OSMIUM CLUSTERS

69 3.1 Introduction

74 3.2 Reactions of 0s3(C0) 10(MeCN)2

74 3.2.1 Reactions of 0s3 (CO) io(MeCN)2 with Arenes of the Type

C6115R (where R = F, Cl, Br, and CH 3)

82 3.2.2 Reactions of 0s 3(CO) 1o(MeCN)2 with C6H4(CH3)2

87 3.2.3 Conclusion

89 3.3 Reactions of 0s 3(C0) 10(MeCN)2 with a-methylstyrene, styrene,

and 1,3 diisopropenylbenzene

89 3.3.1 Results and Discussion for Reaction with a-

methyistyrene

91 3.3.2 Results and Discussion for Reaction with styrene

92 3.3.3 Results and Discussion for Reaction with 1,3

diisopropenylbenzene

92 3.3.4 Conclusion

94 3.4 References

95 CHAPTER FOUR- REACTIONS OF OSMIUM ARYNE CLUSTERS

95 4.1 Introduction

95 4. 1.1 Attack on Metal Framework

98 4.1.2 Attack on the Arene Ring

100 4.2 Reactions of Clusters 0s 3(C0)9(t-H)2(C6H2R'R2) Towards

Acylation

105 4.3 Reaction of 0s3(C0)9(.t-H)2(C6H3F) with 2-butyne

114 4.4 References

115 CHAPTER FIVE- EXPERIMENTAL

115 5.1 General Experimental Procedures and Instrumentation

118 5.2 Experimental Details for Chapter Two

124 5.3 Experimental Details for Chapter Three

131 5.4 Experimental Details for Chapter Four

135 5.5 References

136 5.6 Crystallographic Tables

Chapter One

Chapter One

INTRODUCTION

The introduction which follows in this chapter is divided into two distinct

sections, Friedel-Crafts Acylation Reactions and Cluster Chemistry. This is to reflect,

and give a background to, the later work contained in this thesis.

In the first section the introduction deals with Friedel-Crafts Acylation

Reactions, and covers in detail the different aspects and areas of Friedel-Crafts

Aromatic Ketone Synthesis. This is to give a background to the work carried out in

Chapter 2, which is concerned with using Palladium complexes as acylation catalysts.

In the second section the introduction deals with Cluster Chemistry, covering

in detail the Surface Cluster Analogy, and the synthesis, reactions, and bonding modes

in Trinuclear Arene Cluster Chemistry. This is to give an understanding of this type of

chemistry in relation to the cluster work carried out in Chapters 4 and 5.

1 FRIEDEL-CRAFTS REACTIONS

1.1 Introduction

Friedel-Crafts reactions are named after the two men who first discovered and

observed the action of aluminium chloride in organic reactions, Charles Friedel and

James Mason Crafts. Fnedel-Crafts reactions, as they are now termed, have grown

with the Grignard methods to be the most widely used, and versatile tools of organic

chemistry, covering aromatic and aliphatic systems alike.

1

Chapter One

1.2 Historical

Before Friedel and Crafts first publication (l) earlier workers had reported

reactions similar in character. In 1869 Zincke 2 reported the formation of

diphenylmethane during the attempted synthesis of 3-phenylpropionic acid. The

reaction was carried out in a benzene solution in the presence of Cu or Ag to remove

the metal chloride which is formed with the chlorine gas. However he noted the

evolution of HCl gas and the formation of diphenylmethane.

CHC1 CH2CH2COOH

+ CICH2COOH + C12

CH2C1

II I + AgorCu IN

+ HCI

Scheme 1.2.1: synthesis of 3-pheny1propiomc acid and diphenylmethane

In Zincke's later work ' 2 , he investigated the similar reactions of toluene,

benzene, and xylene. In these reactions he discovered that Zn powder enabled the

reaction to proceed more easily. Later papers (4,5) re-emphasised the use of Zn or

reduced Fe.

The first mention of acylation related to the latter Friedel-Crafts method

appeared in a communication by Grucarevic and Merz, 6 and was closely followed by

a paper by Zincke. 7 In Zincke's paper he attempted to synthesise dibenzoyl from

benzoyl chloride, in the presence of Cu, Zn, or Ag. Instead he noted evolution of HCl

gas and the formation of benzophenone. He also reported similar reactions with

toluene and xylene.

napier tjne

0 II

O(coc1 a + + I II.I

Scheme 1.2.2: Reaction between benzoyl chloride and benzene at room temperature

Grucarevic and Merz in their main communication 8 confirmed Zincke's work

and they then extended it to more aromatic compounds.

None of these papers realised that it was the metal chloride that catalysed the

reaction although some had observed its formation. It was left to Friedel and Crafts to

prove and demonstrate that it was the metal chloride that was the catalyst. Their first

two communications (9,10) gave details of the action of aluminium chloride on amyl

chloride to produce hydrocarbons and HC1 gas. They realised that the residues were

longer chain hydrocarbons that had been produced by combining the shorter chain

hydrocarbons in the reaction.

They then extended this work to attempt to create a general synthesis suitable

for use with any hydrocarbons, and they succeeded in synthesising amyl benzene(ii)

from amyl chloride, benzene and aluminium chloride.

II I + CH3(CH2)4C1

0((CH2)4CH3 +

Scheme 1.2.3: Reaction between benzene and amyl chloride in the presence of Aid 3

In a further paper " 2 they described the synthesis of diphenylmethane,

triphenylmethane, acetophenone, benzophenone, phthalophenone, and anthraquinone.

The paper attempted to show the generality of their method and to work out some of

the reaction's limitations.

C]

Chapter One

In later years "2 ' 7 they extended the scope of their reaction to include the use

of organic bromides and iodides, and to use aluminium bromide and aluminium iodide

to give alkylated and acylated products. They also extended their work into the use of

other metal halides, zinc chloride and ferric chloride, and they proved that the earlier

work by Zincke and others was due to the presence of zinc chloride acting as a

catalyst in the reaction.

1.3 Aromatic Ketone Synthesis

1.3.1 Introduction

The essential reaction of Friedel-Crafts ketone synthesis is between an acyl

component and an aromatic substrate in the presence of a catalyst to give an aromatic

ketone. A typical reaction is shown below in Scheme 1.3.1.1.

RCOC1 + ArH Aid3

" ArCOR + HO

Scheme 1.3.1.1: General equation for the reaction of an acyl chloride with an aromatic substrate

A variety of acyl groups can be used, and are usually acids, anhydrides or

esters.

Aid 3 ArH ± RCOX ArCOR + HX

ArH + (RCO)20 A103

b. ArCOR + RCOOH

ArH + RCOOH' BF3 ArCOR + H20

Aid 3 ArH + RCOOR' ArCOR + R'OH

Scheme 1.3.1.2: General reactions of acyl halides, anhydrides, carboxylic acids, and esters with an

aromatic substrate

4

Chapter One

1.3.2 Mechanism

The mechanism for the acylation reaction can proceed in one of two ways;

O—MX3 I O—MX3

R— + AsH I R—C—X I I + X [ ArH

Path I I 0+ MX' O—MX3 O—MX3

R—C R—C __ 4 R—C

x Ar Ar

+ IIX

OtMX3

R—C - - MX,- + RCO

Path B 0+ UX - 3

RCOArH MX4

R—C' Ar

'I

Scheme 1.3.2.1: Reaction mechanisms for aromatic ketone synthesis

Path A involves a reagent which may or may not be solvated. Gore (18) showed

that Path A is always the more likely mechanism, unless there are steric

considerations in the acyl halide or aromatic substrate.

Path B is an acylium cation mechanism (19) and is the more likely mechanism

when sterically bulky reagents are used, and when the substitution position on the

aromatic is sterically hindered. The structure of the acylium cation intermediate was

first proposed by Meerwein, 20 and results of exchange studies (21) have suggested the

Chapter One

presence of acylium cations in solution. In these experiments halogen exchange was

observed between aluminium halides and 2,4,6-tribromobenzoyl halides. It is argued

that the steric hindrance of this aromatic group precludes the formation of any other

intermediate except the acylium cation.

1.3.3 Ratios and Addition Sequences

In practice the use of the catalyst in the stoichiometric amount gives the

maximum total yield of ketone. A deficiency of catalyst will lower the overall yield

because of incomplete use of the acyl compound. Insufficient use of aluminium

chloride may cause self-condensation of the partially complexed ketone, as in the

formation of dypnone in the attempted acylation of benzene. (22)

The stoichiometric equations 123-291 for the formation of the reactive complex

with aluminium chloride are shown below in Scheme 1.3.3.1.

RCOC1 + Aid 3 P, RCOCIAIC13 (1)

RCOOH + 2A1C13 o RCOCIA1C13 + A100 + HCl (2)

RCOOR' + 3A1C13 ip RCOCLAICI3 + AI00 + R'Cl (3)

(RCO)20 + 3A1C13 01 2RCOCLA1C13 + A100 (4)

Scheme 1.3.3.1: Stoichiometric equations for the formation of the reactive complex

In practice the ratio of moles of aluminium chloride:acyl component of 1.1:1

has been found to be optimum for equation 1,(25) at least 2:1 for equation 2.2:1

for equation 3,(31) and at least 3:1 for equation 4(32) Similar ratios have been found

for other catalysts, and experimental values found to be in close agreement with those

calculated.

Chapter One

Gradual addition of one component to a mixture of the other two, usually in a

solvent, provides the three general experimental methods used in Friedel-Crafts

ketone synthesis.

Elbs Procedure

This is the most widely used procedure, and is the one which Friedel and

Crafts used themselves. It was further developed by Elbs, 33 and in this method the

catalyst is added last to the acyl chloride/aromatic mixture.

Bouveault Procedure

In this method the acyl halide is added last to the catalyst/aromatic mixture. (34)

This procedure is generally not preferred as the presence of hydrogen halide, formed

after the first addition of acyl halide, or from impurities, can cause extensive

isomerisation or disproportionation.

Perrier Procedure

In the Perrier method (31,11) of the reaction the aromatic substrate is added last

to the catalyst/acyl halide mixture. The reaction is generally carried out in carbon

disulfide, dichloromethane, or ethylene chloride as the solvent, because the complex

RCOC1.A1CI 3 is soluble in these solvents, but aluminium chloride is not. This means

that excess aluminium chloride will not be used in the reaction. When the aromatic

substrate has been added, the acylation product tends to be insoluble and is therefore

difficult to purify.

1.3.4 Solvents

A variety of solvents can be used in Friedel-Crafts ketone synthesis.

Nitrobenzene and carbon disulfide are the most commonly used, and these at the same

time govern the type of the reaction taking place. A polar solvent, such as

nitrobenzene, not only dissolves aluminium chloride but also the RCOC1.A1C1 3

7

Chapter One

complex and the aluminium chloride complex of the ketone. (17) This makes the

reaction essentially homogeneous in nature.

In a non-polar solvent, such as carbon disulfide, neither the aluminium chloride

or the complex RCOC1.A1C13, are appreciably soluble, making the reaction

heterogeneous in nature. In an intermediate solvent, such as dichloromethane,

aluminium chloride is not appreciably soluble, (3 ') but the complex RCOC1.A1C1 3 is.

The main factors governing solvent choice have been discussed by Gore (39) and

the main influence is the yield of the ketone obtained in the reaction. The choice of

solvent can affect the acylation rate observed for the reaction, as in the case of the

benzoylation of toluene. (40) The relative rates varied form 1.0 in 1,2,4-

trichlorobenzene, to 30 in excess benzoyl chloride.

Minor differences in the orientation of substitution have been observed with

benzene derivatives. For example in the case of the benzoylation of chlorobenzene,

twice as much meta-isomer is formed in nitrobenzene as in using excess

chlorobenzene. 41

1.3.5 Catalysts

1.3.5.1 Aluminium Chloride

Aluminium chloride is the main catalyst used in Friedel-Crafts reactions,

mainly because of its high catalytic activity and relative cheapness.

The purity of the aluminium chloride may have some influence on the yield of

the product, 42 as in the case of the benzoylation of benzene where the use of pure

aluminium chloride (99.95%) gave a higher yield than commercial aluminium chloride

(98%). Trace amounts of ferric chloride have been reported to cause increases in

Ll

Chapter One

yields (43) and to exert an accelerating effect on the reaction (44) when used in

conjunction with aluminium chloride.

Traces of water have been used to moderate otherwise violent reactions, (45)

and alternatively to accelerate sluggish reactions. 46 In other investigations 47 '48 it has

been observed that a little water added to the anhydrous aluminium chloride causes

considerable improvements in yield. In general practice perfectly anhydrous conditions

are difficult to obtain, and the activating influence of water has been explained (49) by

the formation of hydrates of the type [A1X 30H] H , which probably function like

other strong proton acids.

The use of partially hydrated or pure anhydrous aluminium chloride can result

in different products being formed, as in the case of the reaction of trichloroacetyl

chloride and benzene. If moist aluminium chloride is used the product observed is

trich1oroacetophenone, 50 but with anhydrous aluminium chloride the product is

triphenylvinyl alcohol. (51)

c13cc0

Moist

CI3CCOCI + I A

Anhydrous Ph3CCHCHOH

Figure 1.3.5.1.1: Reaction of trichioroacetyichioride with benzene with both anhydrous and moist

Aid 3

1.3.5.2 Side Effects

The high catalytic activity of aluminium chloride, i.e. its high Lewis Acid

strength, 52 brings certain disadvantages. Aluminium chloride can give rise to side

Chapter One

reactions, such as intramolecular migration of alkyl groups, (53) or the removal of alkyl

groups, especially tertiary groups. (54) (Scheme 1.3.5.2.1)

CH3 CH3

COCH3 Aid 3

a-i3coa

R

C(CH3)3 CI-131, C -10

A1a3 II Qi3dOQ

C(CH3)3 C(CH3 )3

Scheme 1.3.5.2.1: Example of intramolecular migration and removal of alkyl groups

Other side effects include the replacement of halogen atoms, and the splitting

of ortho-alkoxy groups, both within the acyl halide and within the substrate.

1.3.5.3 Other Metal Halides

Other highly active metal halides recommended for use in acylation reactions

include A1Br3 , FeC13, FeBr3, SbCI 5 , SbC13, TiC14, GaC13, TeC14, TeC12, ZrC14, and

ZnC12 . Some Of these halides give yields which are comparable to those obtained with

aluminium chloride.

Aluminium bromide and iodide are both active catalysts, but aluminium

fluoride has been shown to be inactive in acy1ations. 5" An example of the use of

aluminium bromide (16) is shown in Scheme 1.3.5.3.1

10

Chapter One

CH3

CH3 OCH3

COCl CH3 CH3 +

Co

CH3 CH3

OCH3

Scheme 1.3.5.3.1: Reaction of 1-acetylmesitylene with anisole using AIBr 3 as a catalyst

In a comparison of the effectiveness of the aluminium halides, (") it was found

that their effectiveness depends upon the reaction, but that aluminium iodide is more

useful for alkylation than for acylation. The iodide also makes the products difficult to

purify because free iodine is formed in small but significant amounts.

Cod 0 II

I + a A113,j II

Scheme 1.3.5.3.2: Formation of benzophenone using A113 as a catalyst

Dermer 57 ' 58 investigated a series of halides for their effectiveness in the

acylation of toluene with acyl chloride. He found the sequence to be A1C1 3> SbCI5>

FeCI3> TeCl2> SnC14> TiC14> TeC14> BiC13> ZnC12. This sequence generally holds

true for the simpler aromatic compounds, but when the aromatic substrate becomes

more complicated different metal halides work better than others. Examples of the

reactions catalysed by some of the mentioned metal halides 593 are shown in Table

1.3.5.3.1.

11

Chapter One

CATALSYST ACYL COMP AROMATIC PRODUCT REF.

FeC13 CH3COC1 m-xylene (CH3)2C6H5 COCH3 59

GaC13 CH3COCL benzene acetophenone 60

MoC1 5 CH3COCI toluene CH3C6H5COCH3 61

SbC13 C6H5COC1 benzene benzophenone 62

SbC15 C6H5COCI benzene benzophenone 62

SnC14 CH3COCI toluene CH3C6}{5COCH3 57,58

TeC12 CH3COC1 toluene CH3C6H5 COCH3 57,58

TiC14 CH3COC1 toluene CH3C6H5COCH3 57,58

ZnC12 CH3COC1 benzene acetophenone 63

Table 1.3.5.3.1: Table of metal halides and the reactions they catalyse

1.3.5.4 Metals

Some metals in their powdered form have been used as effective acylation

catalysts in conjunction with acyl halides, usually in the absence of solvents, and at

elevated temperatures. The metals which have been used are Zn, Cu, Ce, Mo, Al, W,

and Fe. Examples of some of the reactions which involve their use are shown below in

Table 1.3.5.4.1.

CATALYST ACYL COMP AROMATIC PRODUCT REF

Zn, Ce Phthalyl Cl benzene anthraquinone 64

Cu, Mo, Fe Benzoyl Cl toluene 4-methylbenzophenone 64

Al, Mo, W Benzoyl Cl m-xylene dimethylbenzophenone 64

Table 1.3.5.4.1: Table of metals and the reactions they catalyse

12

Chapter One

Their mode of action is not understood, but in the case of the electropositive

metals Zn, Al, and Fe, it appears probable that the corresponding metal halide is first

formed.

1.3.5.5 Acids

Mineral acids have been used in special cases with significant success. Acids

such as concentrated sulfuric acid, HCI0 4, and HOS02 have been the most widely

used, and the mechanism probably involves the formation of the free acylium cation.

In the diagram shown below, an example of the use of two of these acids 65 is shown.

(RCO)20 + HC104 RCO + RCOOH + C104• (5)

RCOC1 + AgC10 4 ' RCO + AgC1 + C104 (6)

RCOC1 + H2SO4 RCO + HCl + HSO4 (7)

CH3

CH3

+ (CH3CO0 H2SO4

CH3 N

CH3 NCOCH3

OCH3 OCH3

I 1 + (CH3CO)20

COCH3

Scheme 1.3.5.5.1: General reaction scheme using mineral acids as catalysts, and examples of

specific reactions in which they are used

13

Chapter One

A series of phosphoric acids; .H3PO4 (100% and 85%), H3P03, H2PO3F, and

H4P207, have been shown to be effective in the acylations of thiophene and furan. 66

~S3 + (CH3CO)20

P acid IL,

COCH3

II II + (CH3CO)20 Pacid [111

OCOCH3

Scheme 1.3.5.3.2: Acylation of thiophene and furan using phosphorous acids as the catalyst

Weaker acids, such as alkanesulfonic acid, sulfoacetic acid, p-toluenesulfonic

acid, have been less successful in acylation reactions, and the more powerful the acid

is, the more chance there will be a successful reaction.

1.3.5.6 Non-metallic Catalysts

Boron trifluoride, and its complexes with ether, methanol, and acetic acid are

pre-eminent among non-metallic halides capable of catalysing acylation reactions.

Li + (CH3CO)20 BF3

S COCH3

COCH3

I II + CH3COF I II

Scheme 1.3.5.6.1: Acylation of thiophene and benzene using BF3 as the catalyst

In the second example shown (67) the acyl fluoride is probably converted by the

catalyst into acylium fluoroborate, [CH3CO 4 ] [BF4 }, which then attacks the substrate.

14

Chapter One

The chloride (68) and bromide (69) of boron are both active catalysts, but they are

not as effective, or their use as widespread as the trifluoride. The chloride reacts best

with anhydrides, and the bromide with acids, in conjunction with aluminium chloride

or tin chloride.

Phosphorous pentachioride has been used in the benzoylation of naphthalene,

and phosphorous chloride on its own, 70 or in conjunction with zinc chloride, has

been used more widely, and with some success. (71)

Trace amounts of iodine have proved to be useful catalysts for the acylation of

reactive substrates, such as anisole, 72 thiophene, 73 and mesitylene. 74

1.3.6 Acyl Component

The acyl component in Friedel-Crafts acylation reactions may be any

substance capable of being converted into a potential acylium cation, or other reactive

entity, under the influence of a catalyst or heat alone.

For the introduction of an acyl group into an aromatic nucleus, RCOC1 is the

most frequently used, but other reagents which can be used are carboxylic acids,

esters, and anhydrides, as discussed.

1.3.6.1 Acyl Halides

The reactivity of the acyl halides when used in conjunction with aluminium

chloride has been shown to decrease with the increasing electronegativities of the

halogens. 55 This makes the order of reactivity RCOI> RCOBr> RCOC1> RCOF, and

this sequence generally holds for the simple reactions with benzene, anisole, and

15

Chapter One

mesitylene. As the aromatic substrate becomes larger and more complex, the

maximum reactivity is generally found with the bromide or the chloride.

The organic R group in an acyl halide can be almost any organic fragment, for

example, unsaturated aliphatics, hetero-aliphatics, and polycyclic arenes. Generally,

the simpler the R group, the higher the yield achieved in the reaction. For example, in

the acylation of toluene using aluminium chloride 75 the order of reactivity for three

acyl chlorides was acetyl chloride> benzoyl chloride> 2-ethylbutyl chloride.

For the simplest R groups, aluminium chloride and the acyl chloride, are

generally used. Replacement by acyl bromides has resulted in improved yields in some

cases, but the chloride is generally used.

1.3.6.2 Anhydrides

The use of anhydrides is common, and two mechanisms exist in their use. In

the first only one of the acyl components is used , whilst in the second both acyl

components are used.

(RCO)20 + 2A1C13 RC00A1C12 + RCOCLAIC13

(RCO)20 + 3A1C13 2RCOCLA1Cb + AIOC1

Scheme 1.3.6.2.1: General reaction scheme using anhydrides and A1C1 3

There are two factors which govern which mechanism operates; first the

amount of catalyst used, and second the reactivity of the acyl group. The more

reactive the acyl group, the more likely both components will be used, providing there

are three or more moles of catalyst used.

16

Chapter One

When a mixed anhydride is used the situation becomes more complex,

especially if a deficiency of catalyst is used. This means that only one of the acyl

residues will become activated.

RCOOCOR' + 2A1Cb 10 RCOCLAlCl + R'COOA1Cl2

Scheme 1.3.6.2.2: General reaction scheme using a mixed anhydride

If sufficient catalyst is used, then both acyl residues will be activated, and two

products will be formed, reactivity permitting. For example when benzoic acetic

anhydride was reacted with benzene in the presence of aluminium chloride,

benzophenone and acetophenone were obtained. 76

COC 6H5 COCH3

r') (C6H5CO)O(CH3CO) + L) + 16

7% 12%

Scheme 1.3.6.2.3: Reaction of benzene with benzoic acetic anhydride in the presence of A1C1 3

1.3.6.3 Acids

Acylation using carboxylic acids and aluminium chloride has occasionally

proved attractive, providing the substrate is inert to the catalyst, and when the acid

chloride or anhydride is obtained only with difficulty. (77)

The acylation of phenols using carboxylic acids and anhydrous zinc chloride is

known as the Nencki Reaction, 78 ' 79 but this reaction often gives low yields and

undesirable by-products. (80)

17

Chapter One

OH a + CHCOOH zna2

OH OH

+ rCOCH3

C OCR3 2-10%

2-10%

Scheme 1.3.6.3.1: Nencki Reaction, acylation of phenol using acetic acid and A1C1 3

This reaction has been largely superceded by three newer acylation

procedures. The first uses boron trifiuoride, 81 ' 82 the second uses polyphosphoric acid

(PPA), 83 ' 84 and the third is known as the Fries Rearrangement (see later), which does

not use an acid as the acyl component.

OH OH

II + RCOOH PPA

L1jJ >70%

COR

OH OH

+ RCOOH BF, I

I >70%

COR

Scheme 1.3.6.3.2: Two newer methods for the acylation of phenol using PPA and BF 3

BF3 tends to work better for polycyclic phenols than the PPA. The yields

achieved are excellent, there is little decomposition, and the work up and purification

of the products is easily achieved.

1.3.6.4 Esters and Ketenes

The use of an ester as an acyl component results in both alkylation and

acylation of the aromatic substrate, as in the case of ethyl acetate reacting with

18

Chapter One

benzene in the presence of aluminium chloride. Two products are obtained,

ethylbenzene and acetophenone.

Ketene has been used as the acyl component with some success, usually using

aluminium chloride as the catalyst, as in the reaction of ketene with benzene, anisole,

or naphthalene (85,86)

COCH3 C2H5

+ CH3COC2H5 + Ala3

IN

acylation alkylation

COCH3

+ CH2=C=O A103

I 1 ketene

Scheme 1.3.6.4.1: Acylation of benzene using an methyl ethylester and ketene

1.3.7 Houben-Hoesch Reaction

In synthesising hydroxyaryl ketones from phenols and nitriles, Hoesch noted

the difficulties encountered in preparing this class of compound, either by the normal

Friedel-Crafts method using polyhydric phenols and acyl chlorides, or by the Nencki

method using phenols and carboxylic acids. These routes often led to compounds

which had more than one acyl group.

In a series of publications, Gattermann 8793 showed that aromatic aldehydes

are readily prepared by reaction of aromatic compounds with HCN, in the presence of

HC1 and aluminium chloride. This reaction is now known as the Gattermann Reaction.

19

Chapter One

OH OH OH

HCN &CH=NRHCI

IN

HO

LCH=o I II

(H A103)

HO HO >

Scheme 1.3.7.1: Gattermann Reaction, preparation of aromatic aldehydes

Hoesch 9497 modified the reaction using nitriles instead of HCN, and replaced

aluminium chloride with zinc chloride. Houben (9"101 then made a thorough

investigation into the scope and limitations of the reaction between aromatics and

nitriles. From then it has been used principally with polyhydric phenols and their

ethers.

OH OH NH.HC1

RCN L{cR

HO Ha. za2

HO

OH NH OH 0

C' R

'& R HO> HO

Scheme 1.3.7.2: Acylation of polyhydric phenols using RCN and ZnC1 2

The reaction is known as the Houben-Hoesch Reaction, and the mechanism is

thought to occur via electrophilic attack of a carbonium ion in a normal aromatic

substitution process.

20

Chapter One

e R—C=N + IN R—C=NH

OH OH H

NH if R II ____________________

HO +

HO H

I II C'

/ OH NH

HO"& 11

Scheme 1.3.7.3: Mechanism of the attack of RCN on polyhydric phenols

1.3.8 Fries Rearrangement

Fries attempted to find a method which was more suitable than the Friedel-

Crafts method for the preparation of oriho-chloroacetyl phenols. He achieved good

results with the phenolic esters of chioroacetic acid and aluminium chloride, (111,112)

and in this way he prepared ortho- and para-chioroacetyl phenols. Fries also observed

a similar rearrangement in the case of the phenolic esters of acetic acid." 2

21

Chapter One

OH OCOCH2C1 OH

COCH2C1 Ala3

COCH2C1

OH OCOCH3 OH

Ala3 COCH3

AKi3

COCH3

Scheme 1.3.8.1: Fries Rearrangement of the phenolic esters of, chioroacetic acid and acetic acid

The Fries Rearrangement can be expressed in general terms by the reaction

below.

ArOCOR HOArCOR

where R = acid, Ar = phenolic

Scheme 1.3.8.2: General equation of the Fries Rearrangement

Although phenols may be acylated directly using aluminium chloride and acyl

halides, these ortho- and para-hydroxyketones are more frequently synthesised using

the Fries Rearrangement. ' 13 This is a reaction whereby an ester of a phenol is

transformed into an ortho- or para-hydroxyketone, in the presence of aluminium

chloride.

OCOR OH OH a J _COR +

COR

Scheme 1.3.8.3: Synthesis of ortho- and para-hydroxyketones using the Fries Rearrangement

22

Chapter One

The overall preparation requires two steps from the phenol, i.e. preparation of

the ester and the rearrangement. However the yields are usually better than those

obtained by direct Friedel-Crafts acylation of the phenol. The normal procedure is the

action of aluminium chloride on the ester in nitrobenzene for several hours and then

rearrangement. Aluminium chloride is the normal catalyst used, although SnC4,TiC1 4 ,

FeCl3, and ZnC12, have been shown to be active. (114)

Although the reaction produces a mixture of two products, they can

frequently be separated by distillation. The composition of the ratio of isomers can

depend on the reaction conditions employed, as in the case of the rearrangement of

meta-cresyl acetate, 115 in which the ratio depends upon the temperature employed.

Other experimental variables, such as solvent and proportion of catalyst can also

influence the product ratio.

1.4 Conclusion

Friedel-Crafts and related reactions are widely used as synthetic tools in

organic chemistry. The essential reaction discovered by Friedel and Crafts has opened

up a large area of related reactions and syntheses, all of which have had large areas in

the scientific literature devoted to them.

The Fnedel-Crafts Aromatic Ketone Synthesis has been shown to vary widely,

with large numbers of species able to take part in the reaction. The variety of

catalysts, aromatics, and acyl components is vast, and the number of reactions they

can take part in is huge.

23

Chapter One

2 CLUSTER CHEMISTRY

2.1 Introduction

The term cluster is commonly defined as a metal complex with two or more

metal atoms mutually bonded to each other. As such, the first clusters to be identified

were metal chioro-salts of the type W 2C193 and Re3 C1 123 which led to the realisation

of the existence of metal-metal bonds within complexes. A second class of clusters

the metal carbonyls, were later discovered with the emergence of the X-ray structural

characterisation of Fe 2(CO)9 in 1939,(' 16,117) and later the characterisation of

Mn2(C0) 10 in 1963.(h18) This represented the first example of an unsupported metal-

metal bond in this area of chemistry. Interest in the subject grew with the possibility of

producing new structural types, and this area developed further with effort being

focused on the reactivity of these species with small organic molecules e.g. alkynes,

alkenes, and arenes, to form a large number of compounds, the nature of whose ligand

co-ordinations were precisely defined by solid state X-ray molecular structures.

Muetterties 119 postulated that these bonding modes may not be too dissimilar to

those observed on metal surfaces as found in catalysts, and hence this led to their

proposition as possible models for heterogeneous catalysis and chemisorption, and

this postulation became known as the Surface Cluster Analogy.

2.2 The Surface Cluster Analogy

Although metal carbonyl clusters have been found to act as catalysts, ' 20 for

example [Fe(p.3-00)( 5-05H5)]4 in the hydrogenation of alkynes to alkenes, and

Ru3(CO) 1 2 in the water gas shift reaction, they have not to date found major industrial

application. The analogy of clusters as models for catalysis is now no longer regarded

as totally plausible, although as a model of chemisorption it has been widely applied.

Indeed, a few years after his original proposal, Muetterties 21 published a detailed

24

Chapter One

and critical review of the analogy with respect to chemisorption. This work is now

considered below.

The geometry of a cluster and a surface are usually not comparable, although

notable exceptions to this are the metal frameworks observed for some of the higher

nuclearity clusters: [Rh 13(CO)H3] 2 , [0s ioC(C0)24]2 , and [Rh14(C0)25]4

(124) which represent fragments of hexagonal close packed, cubic close packed, and

body centred cubic lattices respectively (Figure 2.2.1). However, a flat metal surface

cannot be adequately modelled by the square and triangular faces which are exhibited

by these and other polyhedral clusters. It has been suggested that they could act

instead as models for films or small particles on solid supports rather than as single

metal crystals. However, when using spectroscopic methods to study the products

resulting from chemisorption processes on poorly defined surfaces such as these, in

which the geometry of the surface is random and not ordered as in crystalline samples,

problems arise in the interpretation of the vibrational data. Because a range of

possible sites are present on which adsorption could occur, assignments of vibrational

modes can be ambiguous. Hence such systems tend not to be studied.

(a) fRhl3(CO)24H3)2 ' (b) (OsiC(CO)24) 2 (c) (Rh14(CO)25]

h.c.p. C.C.P. b.c.c.

Figure 2.2.1: The molecular geometries of the clusters [Rh 13(C0)24H3]2 , [Os1oC(CO)24] 2 , and

[Rh14(CO)1.

25

Chapter One

Even though comparable geometries are possible in clusters and surfaces,

further problems arise from the co-ordination number of the metal atom to its

neighbours, and from the metal-ligand connectivity. The co-ordination number is

usually much greater for an atom on a metal surface, typically six to nine, than for an

atom in a cluster which shows a metal-metal connectivity of two for triangular, three

for tetrahedral, and four for an octahedral geometry. The co-ordination number only

approaches that for the surface in some of the larger polyhedra such as

[Rh13(CO)24-13 ] 2 with a co-ordination of five, and a maximum of seven in the cluster

[Rh 14(CO)25 ]4 . This difference results from the close packing of metal atoms in the

bulk and their co-ordination to atoms in the sub-layer. The metal-ligand connectivity

is comparatively larger for the cluster, in the region three to five, than for the surface

which is typically one or less, and again highlights some incompatibilities between the

two regimes. Of particular importance is that the local atomic and electronic structure

of a surface is influenced by other atoms in the layer and sub-layers, for which there is

no possible cluster analogue.

Theoretical calculations have shown that a cluster of metal atoms becomes

metal-like only with nuclearities in the range 13-19 for Ni and Pd and 30-5 1 for

Ag. 112 However, these large metal-like structures show properties which are

dissimilar to the bulk metal, and only approach a truly bulk metallic state with higher

nuclearities.

A consideration of these factors clearly shows that a cluster and a metal

surface are quite distinct in nature. Hence, it is not possible to consider a cluster to

closely model a metal surface. However, the Muetterties analogy was not based on

this, although it is often misconstrued, but rather considered the "comparison between

a discrete or molecular metal cluster which has a polyhedral metal core and a

periphery of ligands, and a metal surface with a similar set of ligands chemisorbed at

the surface". Thus, it is suggested that there is no real difference in the metal-ligand

bond formed in these two extremes. Indeed, calculations have shown that it is

26

Chapter One

reasonable to approximate the adsorption of a group of atoms or a single molecule as

involving the interaction with only a small group of metal atoms, although longer

range interactions are important. For example, experiments have shown that, the

binding energy of CO on an array of Ni atoms is not greatly affected by the size of the

array. (126) The co-ordination of the ligand to a cluster is thus representative of similar

plausible co-ordination types on metal surfaces, and indeed appropriately substituted

clusters have been prepared which show many of the known adsorbate geometries. (127)

Clusters can therefore be regarded as reasonable models of chemisorbed

species on metal surfaces.

The techniques of surface analysis have in the past been considered to be

somewhat imprecise. However, as technological advances have been made, and new

techniques introduced, problems such as spectral resolution have been overcome, so

that for example using the vibrational techniques (1211 RAIRS (Reflection Absorption

Infra Red Spectroscopy) or DRIFTS (Diffuse Reflectance Infra Red Spectroscopy),

JR spectra can typically be recorded to 4 cm' resolution, although EELS (Electron

Energy Loss Spectroscopy) can only give a Ca. 10 cm-1 resolution. However the

interpretation of such data is not always straightforward, and hence a number of

techniques are usually combined to give complementary information. The comparison

of a proposed adsorbate type and co-ordination geometry with that observed in a

cluster has often proved a valuable technique in such analyses.

Chemisorption processes at metal surfaces fall into two main classes:

associative, in which there is no fragmentation, and dissociative, which results in

bond cleavage of the chemisorbed fragment e.g. dissociation of H2 gives M-H, and

examples of these processes have been reported for clusters. Likewise, mobility can

be considered as dissociative or non-dissociative. The mobility of ligands has been

established by NMR for clusters, for example the interconversion of Ru6C(C0)i1(11 6-

C6H5Me)(93 - n2 :ii 2 : i2-C6H5Me) and Ru6C(CO) i i(i6-C6HsMe)2129 and carbonyl

27

Chapter One

scrambling in M3(CO) 1 2 (M= Fe, Ru, Os). (130) The techniques of field ion microscopy

and more recently the pioneering work of Bradshaw "31 on PLEEM (Photoemission

Low Energy Electron Microscopy) have shown the mobility of ligands on metal

surfaces. PLEEM is one of the most fascinating, innovative and important techniques

to have been conceived in surface science, and has allowed the migration of molecules

on metal surfaces to be observed and recorded in real time on video tape.

Only two general examples of the analogy are cited below to typify its

application, although many others have been reported, 132 and its applicability to

surface science has proved to be helpful in interpreting a range of vibrational data.

The view of Ertl ("' ) is that the analogy although imperfect, ' 34 works for structure

and bonding but does not extend to reactivity and catalysis.

2.2.1 Chemisorption of Ethylene on a Pt(111) Surface

EEL spectra were recorded by Ibach et a! (135) for the adsorption of ethylene

on a Pt(1 11) surface at low temperature and at room temperature. Two quite distinct

spectra were observed at these temperatures, and were postulated to result from a di-

c; adsorbed species (a) and an ethylidene species (b) respectively (Figure 2.2.1.1)

H3 H3C H

H2C—CH2

Pt Pt Pt7Pt

Pt a b

C

Figure 2.2.1.1: Proposed bonding modes of ethylene on Pt (I 11)

28

Chapter One

Subsequent LEED (Low Energy Electron Diffraction) studies 11161 led to the

room temperature species being reassigned as the ethylidyne species (c). These

species were further justified by a detailed analysis of the vibrational spectra (IR and

Raman) of the cluster models C O3(CO)9( .t3 CCH3)u 37) and Os2(CO) 8(t2-CH2CH2)'38

which show analogous bonding modes (Figure 2.2.1.2).

H3

/\ (CO)3Co - 7CO(CO)3

(CO)3

H2C—CH2

/ \

(CO)40s Os(CO)4

Figure 2.2.1.2: The model clusters CO3(CO)9(.t3-CCH3) and 0s2(CO)8(j.t-C2144).

2.2.2 Co-adsorption of Benzene and CO on Rh(111)

An interesting example of the surface cluster analogy arises from the LEED

pattern observed for the co-adsorption of benzene and carbon monoxide on a Rh( 111)

surface (139) (Figure 1.2.4), and the comparable bonding mode observed for the cluster

species M3(CO)9(.t3 -C6H6) (M=Ru,Os) ( 140,141) and Ru6C(CO) i j(ii6-C6H6)(t3 -

C6H6)(l 4 la 42) (Figure 2.2.5). The benzene ligand shows co-ordination to a three-fold

site and a rehybridisation of the it orbitals so as to maximise their interaction with the

metal orbitals. This results in the shorter double bonds of the Kekulé benzene lying

directly above the metal centres and the bending of the C-H bonds away from the

metal centres. However, conflicting results have been reported which suggest that the

benzene molecule is adsorbed at a single rather than three-fold metal site and shows

no Kekulé distortion. (143)

29

Chapter One

Rh(lI 1)-(3 x 3)-C6H0 +2C0 II

Rh( 11 I)-02(3) 112 X4}re0.C6H6 + CO

Figure 2.2.2.1: The LEED pattern observed for the co-adsorption of benzene and CO on a)

Rh(1 11)- (30) C6116 + 2 CO surface, and b) Rh(1 1 1)-c(2(3) x4)rect - C 6!!6 + 2 CO surface.

Ru

Ru7tu

Ru Ru 7M M-

Figure 2.2.2.2: The structures of M3(C0)9(.L3-C6H6) (M=Ru,Os), and Ru6C(CO) 31 (p.3-C611)( 6-

C6H6).

Although the JR spectra of the benzene ligand bound to the aforementioned

clusters has been briefly reported, ( '44) a detailed comparison with the vibrational data

for the surface species has apparently not been examined.

Chapter One

2.3 Trinuclear Cluster Arene Chemistry

2.3.1 Introduction

Recently arene cluster chemistry has begun to emerge as an important entity

within the field of organometallic cluster chemistry, although the roots of this subject

date back as far as the 1960's. There is a rich chemistry associated with the arene

ligand in mono- and dimetallic compounds, and complexes of virtually every transition

metal have been prepared. Several review articles concerned with the synthesis and

structure of these compounds have been published.' 45 ' 50

Until recently relatively little effort has been directed towards the arene ligand

and its interactions with cluster complexes. The interest has been focused on arene

clusters of cobalt, ruthenium, and osmium.

Early approaches to arene cluster synthesis involved the direct reaction of the

metal carbonyl with the appropriate arene under refiux. Recently other synthetic

routes have been devised and will be discussed later.

The reactivity of arene clusters has centred on both nucleophilic substitution

reactions on the metal core, and on the aromatic ring.

The clusters produced are diverse, and many different bonding modes of the

arene ligands have been observed. The bonding modes 71 2, 116 and I.L312:12:fl2 have

been observed directly°45148 and others have been postulated. The 93-fl2:12:12 type

has been studied extensively, both on its own and its interconversion to the i6 mode.

31

Chapter One

2.3.2 Structures and Bonding Modes

2.3.2.1 Facial

The facial bonding mode of the benzene ring in the complexes 0s 3(CO)9(p.3 -

71 2:i2 :

112-C6H) and Ru3(CO)9(3-if:112:i2-C6116) are shown in Figure 2.3.2.1.1.

/

Figure 2.3.2.1.1: Facial bonding mode in 0s 3(CO)9(i.L3-11 2 :71 2 :71 2-C6H6) and Ru3(C0)9( 3-7f:1 2 :12-

C)

The bond lengths in these complexes in the benzene ring resemble that of the

hypothetical 1,3,5-cyclohexatriene molecule. The bonds are alternatively long and

short, with the short bonds being those in which the two carbon atoms concerned

interact with the one metal atom.' ° The bond lengths are 1.41A and i.siA in the

Os complex, and 1.41A and 1.45A in the Ru complex. The H molecules were located

directly in the Ru complex, and the C-H bonds were observed to bend out of the C 6

plane away from the Ru triangle by between 21.10 and 21.50 respectively. The

benzene ring and the metal triangle are almost parallel to one another.

The electronic structure of 0s3(C0)9(.t3-112:i2:i2-C6H6) has been subjected to

an ab initio calculation and an MO analysis. ( ... ) The interaction of the benzene with

the Os triangle can be rationalised in terms of donation and back donation, which is

32

Chapter One

favoured by C-H bending. The distortion of the benzene has been attributed to

enhanced back donation, and a decrease in exchange repulsion due to the it-electrons

of the benzene.

2.3.2.2 Apical

The apical bonding mode is shown below in the cluster Os 3(CO)7(93 -

C2Me2)(i6-C61-16).

Figure 2.3.2.2.1: Apical bonding mode in Os3(CO) 7( 3-C2Me2)(16-C6H).

The benzene ligand is now in a terminal position and is bound in the 116

bonding mode. The alkyne bridge is bound to the cluster by two cr interactions and

one it interaction. The average bond length in the benzene is 1.39A, which is shorter

than that in the facially bound ligand.° 52

2.3.3 Synthesis

A large number of arene clusters contain a trinuclear metal framework, and

they have recently been reviewed by Johnson et

The triosmium cluster Os3(CO)9(93-i 2:i2:ii2-C6H6) was the first example of a

cluster found to contain a facially bound arene ring. It was reported along with the

related hexaruthenium cluster Ru6C(CO)u(i 6-C6H)(.t3-i 2 :i 2:i2-C6H4."41 The

33

Chapter One

related hexaruthenium cluster Ru 6C(CO) 11 (16-C6H6)(t3-rl2 :r 2 :r 2-C6H). 141 The

synthetic route to the Os cluster begins with the complex H0s3(C0)9(t3-7i 2 :i 1 :ii 2-

C6H7) which was synthesised from H 20s3(C0) io and 1 , 3 cyclohexadiene. ( 1 S4)

sz:j octane octane Os

0s3(CO) 12 go H20s(CO)10 + 1,3-C6H8 H2, heat heat

OHOs

H0s3(CO)9(C6H7)

Scheme 2.3.3.1: Formation of HOs3(CO)9(3-i 2 :11' :1 2-C6H7)

The complex can also be synthesised from the reaction of 0s 3(CO) io(MeCN)2

with 1,3-cyclohexadiene, and the reaction proceeds via the intermediate cluster

Os3 (CO) io(r14-C6H8). (154b,1 55)

2 eqs Me3NO 0s3(CO)12

MeCN go

Os

MeCN MeCN

0s3(C0) 1 0(MeCN)2

Os 1,3-C6H8

o( Os

Q~, 0s3(CO)10(C51-18 )

S=1 IS

octane

OHOs heat

H0s3(C0)9(C6H7)

Scheme 2.3.3.2: Formation of H0s3(CO)9(,.t3-i 2 :i' :11 2-C6H7) via the intermediate cluster

0s3(C0) 10(14-C6H8)

34

Chapter One

The resultant complex HOs3(CO)9(43-1 2 :1':rl 2-C6H7) can then be converted in

two steps to the desired product Os3(CO)9(.t3-ri 2 :rl 2 :Tl 2-C6H6).

cl [ri3cI[BF4j 1 +

DBU Os Os Os

H L OHOs] o( >Os

[HOs3(CO)9(C6H6)] 0s3(CO)9(C61-16)

Scheme 2.3.3.3: Formation of 0s3(CO)9(43-i 2 :r, 2 :11 2-C6H6)

A hydride is firstly extracted from the facially bound cyclohexadienyl .ring

using the trityl cation [Ph 3C], which yields the cationic benzene cluster

[H0s3(CO)9Q.13-11 2 :i2 :i2-C6H6)1. This cluster is then deprotonated with the non-co-

ordinating base DBU to give the desired product 0s3(CO)9(.t3 -i2 :11 2 :if-C6H6).

The analogus Ru cluster R11 3(CO)9(13 -11 2 :11 2 :ri2-C6H6) was prepared five years

later, (140b) and the reaction scheme was based upon the activated Ru 3(CO) io(MeCN)2

cluster as the hydrido analogue H2Ru3(CO) io of H20s3(CO) io is not available. The

route is shown on the next page.

35

Ru 2 eqs MC3NO

Ru3(CO)12 MeCN Ru Ru

{eCN MCCN

Chapter One

heat

Ru3(CO) 10(MeCN)2

1,3H8 2 eqs Me3NO

1,3C6H

Ru H _Ru

HRu3(CO(C6H7)

[ph3q[BF4 ]

Ru

Ru H _Ru

[HRu3(CO)9(C6H6)J

DBU

Ru Ru

Ru3(CO)9(C6H6)

Scheme 2.3.3.4: Reaction sequence to form Ru 3(CO)9(43-12 :1 2 :ri2-C6H)

36

Chapter One

The route parallels that of the Os analogue, but several more convenient steps

have been incorporated and used. Firstly, I ,3-cyclohexadiene reacts directly with the

Ru3(CO) 1 2 in the presence of two equivalents of amine oxide to yield the clusters

Ru3(CO)9(93-1 2 :11 1 :11 2-C6H7) and Ru3(CO)9Q.3-71 2 :11 2 :11 2-C6116) in one step. The dienyl

cluster can then be converted into the benzene cluster by thermolysis in hexane, giving

a much simpler overall synthetic route. The Os cluster will not react in the same way,

and it has to follow the route in Figures 2.3.3.1, 2.3.3.2, and 2.3.3.3.

2.3.4 Reactions

In the scheme below, there are shown a number of reactions that have been

carried out on the Os3(CO)9(.t3-ri 2 :ri 2 :ii 2-C6H6) cluster.

o,osr

[0s3(C0)9(C6H6R1

os Os-Os

11 JABHEI3)or

4J H4] [Os I

[0s3(C0)9C6H7

[ri 3g[BF4 )

0s3(CO)(C6H5R)

0s3(CO)9(CA)

D4Et20

HBF4.EtO

~=l Os

H0s3(CO)9(C6H7)

4]

Os

O H OS

[1i0s3(C0)9(C6H6)1+

Scheme 2.3.4.1: Reactions on the arene ring of Os3(CO)9(3-i 2 :ii2 :i 2-C6H.6)

37

Chapter One

A detailed study into the reactivity of the benzene ring on the cluster

Os3(CO)9(p3-T1 2 : 2 :i12-C6H6) has recently been carried out. (156)

The increased electrophilic nature of the coordinated benzene ring favours

reactions with nucleophiles in nucleophilic substitution reactions. Good hydride

donors such as Li[BHEt 3] and [NEt4}[BH4] react easily in TI-IF to form the dienyl

cluster [Os 3(CO)9(t3-i2 :i' :i 2-C6H7)f. Exo attack of the hydride has been established

by deuterium labelling experiments.

The benzene cluster can be regenerated by abstraction of hydride from the

anionic cluster [Os3(CO)9(t3-i1 2 :1:i2-C6H7)1 - on treatment with [Ph3C][BF4]. The

anionic cluster can also be protonated with HBF 4 .Et20 to yield the neutral cluster

HOs3(CO)9(p3-TI 2 m':rl2-C6H7), which upon treatment with [Ph 3C][BF4] undergoes

hydride extraction to form the cationic cluster [HOs3(CO)9(L3-1 2 :112 :112-C6H)]. This

cluster can also be generated by treatment of the parent cluster Os 3(CO)9(p 3-i 2 :i 2 :i 2-

C6H6) with HBF4.Et20, which is reversible with DBU.

The cluster Os3(CO)9(3-71 2 :1 2 :12-C6H6) undergoes reaction with the

nucleophilic reagents MeLi and PhLi in THE This results in the substituted

cyclohexadienyl clusters [Os3(CO)9(,.13-11 2 :i1 :112-C6H6R)f, which are a result of exo

addition. Further treatment with [Ph 3C][BF4] results in the neutral clusters

Os3 (CO)9(93-71 2 : : 12-C6H5R).

These reactions display a marked similarity to those for ri6-arenes bonded to a

single metal complex.

Reactions can also be carried out on the metal framework of the parent

Os3(CO)9(43-71 2 :112 :ri2-C6H6) cluster, and they usually involve the replacement of a

carbonyl ligand by acetonitrile.

38

Chapter One

Os Me3NO Os C2H4 Os

O( Os_ O Os MeCN Os

Os3(CO)9(C6H6)

R R

/ Os

Os Os0

Os3(CO)8(C6H6)(MeCN) 0s3(CO)8(C6H6XC2H4)

Me37/"

C2R2 Os

MeCN—O( Os-

0S3(CO)7(C6H6XC2H4)(MeCN)

0s3(CO)7(C6H6XC2R2)

Scheme 2.3.4.2: Reactions on the metal triangle of Os3(CO)9(3- 2 :i2 :11 2-C6H6)

Treatment of the benzene cluster with trimethylamine N-oxide in the presence

of acetonitrile yields the cluster Os3(CO)8(43-71 2 :112 :r1 2-C6146)(MeCN). Treatment of

this cluster with a two electron donor ligand, such as tertiary phosphines and alkenes,

result in the displacement of the acetonitrile and formation of derivatives with

equatorial substitution. The co-ordination mode of the benzene ring is retained. In a

typical reaction, ethylene will react with Os3(CO)8(t3-71 2 :ri2 :n2-C6H6)(MeCN) to

produce the cluster 0s 3(CO)8(.t3 -r1 2:i2 :i2-C6H6)(i1 2-C2H4), in which the ethylene

group occupies an equatorial position on the cluster framework. 1157

The substituted cluster Os 3(CO)8(93 - 2 :1 2 :1 2-C6H6)(T 2-C2H4) will undergo

further carbonyl substitution if reacted with amine oxide and acetonitrile to produce

the cluster 0s3(CO)7(j.i3-i 2 : r12:i 2-C6H6)(ii 2-C21-L)(MeCN). This cluster reacts readily

with alkynes [RCCR'] to form the clusters 0s3(CO)7(p.3-i 2-C2RR')(q 6-C6H6). In this

cluster the benzene has now migrated to a terminal position, and the Os triangle is

face capped by the alkyne." 58

39

Chapter One

Although the Ru3(CO) 12 cluster does not undergo substitution reactions,

treatment with . alkynes in refluxing dichioromethane results in the cluster

Ru3(CO)7(i3-1 2-C2RR')(T1 6-C6H6), which is analogus to the above Os cluster. (14)

2.3.5 Conclusion

The Surface Cluster Analogy, although flawed, does show that clusters can be

regarded as reasonable models for chemisorbed species on metal surfaces. New

surface techniques, when used in conjunction with clusters, can give, a useful insight

into what happens at a metal surface.

With the combined effort of synthesis and spectroscopic methods the field of

arene cluster chemistry has expanded greatly in recent years. Newer techniques in

their synthesis are now much more selective than before. Indirect methods in which

molecules are bonded and then chemically modified are providing useful routes into

previously unobtainable arene clusters. Nucleophilic addition reactions dominate in

the reactions of arene clusters, just as they do in the chemistry of mononuclear arene

complexes.

40

Chapter One: Introduction

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48

Chapter Two

Chapter Two

2.1 Introduction

2.1.1 Palladium Complexes And Their Use In Synthesising CO/alkene Co-

polymers

The discovery in the late 1940's by Reppe and Magin" of a nickel catalysed

co-polymerisation of CO with ethylene to yield a CO-ethylene co-polymer generated

considerable interest. Significant attention was focused on these polyketones because

of the low cost of the CO feedstock. The CO accounts for half the weight of the co-

polymer, thus there are significant savings in the cost of the polymer in comparison

with poly alkenes.

Until recently, reactions to create 1:1 co-polymers gave random co-polymers,

and very few of these contained 50% weight of CO. Developments in transition metal

chemistry has regenerated the interest in these systems, and has led to the discovery of

new catalytic systems capable of producing high molecular weight, strictly alternating

polyketones.

In 1982 Sen and Lai (2) discovered that the palladium complex,

[Pd(CH3CN)4]BF4 .nPPh3 (n = 1-3), catalysed the co-polymerisation reaction of

ethylene or norbornadiene with CO.

[Pd(CH3CN)4] BF4 . n PPh3

ICH2CH2J CH2=CH2 + CO

1000psi, 250C, CHC13 n

Scheme 2.1.1.1: The copolymerisation of CO with ethylene at 1000psi

The synthesis was the first to yield a polymer with a CO:ethylene ratio of 1:1,

with the CO accounting for 50% of the weight of the polymer.

Chapter Two

In a later paper (' ) they were able to use the same complex,

[Pd(PPh3)(CH3CN)4.] BF4 (n = 1-3), to make the same reaction proceed at a lower

pressure of 300 psi.

[Pd(PPh3)(CH3CN)n 41 BF4 11

CH 2=CH 2 + CO ICH2CH2 0; 300psi, 250C, CHC13 n

Scheme 2.1.1.2: The copolymerisation of CO with ethylene at 300psi

They found the complex where n = 2, was the most effective and they

proposed a mechanism for the formation of the co-polymer.

0 0

Pd CO

Pd C2H4

Pd

0 0

CO C2H4 PdH

0 0

Coil. Pd'

C2H.4

[ 0

Scheme 2.1.1.3: The proposed insertion mechanism in the formation of (CCOCH 2CH2CH2)

In their mechanism they propose that the polymer is formed by the alternate

addition of CO and ethylene into the growing polymer chain. They argued that the CO

inserts into the preformed Pd-alkyl bond because of the greater binding ability of the

CO compared to the ethylene, and because there is a greater local concentration of

CO. The mechanism leads. to the possibility for of stepwise build up of the co-

polymer, with control over each step.

50

Chapter Two

Understanding the mechanism of the insertion process is important with regard

to developing new catalytic systems, and improving on those already established.

Subsequent work has investigated this stepwise control over the polymer build up by

investigating different palladium catalysts, and their reactions with alkenes and CO

In 1990 Brumbaugh el al. 4 investigated the insertion of norbornene and

norbornadiene into the complex [(PPh 3 )2Pd(CH3CN)(COR)] (R = Me, Et, Ph).

L Ph3P\ Pd

,COR BF4 + ,

Ph3P CH3CN

+ r Ph3P\

Pd

L p3'

Scheme 2.1.1.4: The insertion reaction of norborene into the Pd-acyl bond

They found that when the R group was electron withdrawing group, i.e. Ph,

the complex was unstable, but when the R group was electron donating, i.e. Me or

Et, the complex was stable for several days.

The crystal structure of the complex revealed that it had a square planar

structure, with the two tnphenylphosphines occupying cis positions, and the 2-

acetylnorborn- l-yl acting as a chelating ligand by coordinating through the norbornyl

carbon and the carbonyl oxygen. Until this point these types of olefin insertion into a

metal-carbon bond had rarely been reported. There are three main factors preventing

51

Chapter Two

the formation of these complexes, although they are thermodynamically favoured.

Firstly the complexes can decompose to secondary products through fl-hydride

elimination. Secondly the products derived from multiple insertions are formed, and

thirdly, kinetic barriers prevent the reaction from taking place.

Similar types of palladium complexes but with bidentate phosphine ligands

were synthesised (6) and their reactivity with a range of alkenes was investigated. (" The

simple complexes (P-P)Pd(CpCH 3)(C1) (where P-P = 1 ,2-bis(diphenylphosphino)

ethane (dppe), 1,3-bis(diphenylphosphino)propane (dppp), and 1,4-bis(diphenyl

phosphino)butane (dppb) reacted with both norbornene and norbornadiene to yield

the inserted acyl complexes.

P\

Pd

,COCH3 norborene I

Lv" CI aD2Cl2

[[>d / cH3 J + Cl.

Scheme 2.1.1.5: The reaction of (P-P)Pd(COCH 3)(C1) with norbornene

They found the reaction rate to be dppbdppp>dppe. They also found that the

reaction proceeded better and in higher yields if the complex was made ionic by

substituting a PPh 3 ligand for the Cl, and by adding silver triflate to produce the

complexes [(P-P)Pd(COCH3)(PPh3)1 + S03CF3 . These complexes would undergo

insertion reactions with a larger range of alkenes, including styrene, 1 -pentene,

norbornene, and norbornadiene.

r COCH3 OTF I CH3

OC' 1.pcnten OTf

[) ( e \ /

L C3CN]

E

[ 112

Scheme 2.1.1.6: The reaction of (P-P)Pd(COCH 3)(CH3CN) with 1-pentene

52

Chapter Two

This enabled the reactions to proceed at ambient pressure and temperature

yielding the desired CO-inserted products. The extra stability exerted by the bidentate

phosphine ligands seems to account for the ease at which the reaction proceeds.

Around the same time de Graaf et al. 8 ' 9 synthesised the analogous Pd

complexes with bidentate nitrogen ligands, instead of bidentate phosphine ligands.

CH3\ /CH3

CH

k Pd ligand = tetramethylethylene diamine (tmeda

CH( "CH3

Figure 2.1.1.1: The complex (tmeda)Pd(COCH 3)(I)

Markies et al.'° made the bpy equivalent complex of the above, and then

reacted both complexes with norbornene and dicyclopentadiene to investigate any

differences in reactivity between the two

N COCH3 LN><I

bipyridyl COCH3

N G N

"'Pd\ I

53

Chapter Two

N COCH3 r N COCH3 1

/ A8OTf OTFPd r >d \ CH3CN /

LN L 'N CH3CN]

norbomenc \di.yclopentadienc

+

CH3

[

+ 0Tf

[

]OTU

FN1 — N

= tmeda and bpy L = bpy only N

Scheme 2.1.1.7: The reaction of [(bpy)Pd(COCH 3)(CH3CN)]OTf with norborene and

dicyclopentadiene

They discovered that the bpy complex is the more reactive of the two, reacting

with both the norborene and the dicyclopentadiene whereas the tmeda complex only

reacts with the norborene.

They found that the reactions would only proceed in the presence of silver

triflate, indicating that the reaction proceeds via ligand dissociation of the acetonitnle,

proceeded by formation of complex. The precipitate formed in the reaction was

identified as AgI, further confirming that the reaction proceeds via the mechanism

shown in scheme 2.1.1.7.

This type of system, using the complex (bpy)Pd(COCH3)(I), was developed

further to allow the controlled stepwise build up of a CO/alkene co-polymer."

0 54

Chapter Two

+ OTF

cOcH3 I COCH3 AgOTf ~-N

"Pd CH3CN

CH3CN norbomene

-1 + OTf CH3

(

O ,

f y CO, NaX

I I I 'Pd

-

/

OTf aectone

N' X UIJ 0 ' othoe

+

OTf

Scheme 2.1.1.8: The stepwise build up of a CO/norborene co-polymer using the complex

(bpy)Pd(COCH 3)(I)

The reaction is a controlled stepwise build up of the CO/alkene chain, using 1

equivalent of the complex to produce a polymer. The inserted complex with the five

membered Pd-acyl ring is synthesised as before with acetonitrile, silver triflate, and

norbornene. The resultant complex then undergoes further CO insertion in the

presence of a large excess of sodium halide, Cl or I. This complex can then undergo

further insertion of norborene, allowing the stepwise build up of the CO/norbornene

co-polymer.

55

Chapter Two

2.1.2 Industrial Background

The work specifically in this chapter was funded by Zeneca in Grangemouth,

where they have recently built a new fiuorobenzene plant. This plant currently runs at

around 50% capacity, and they were specifically interested in the reactions of

fluorobenzene to produce two target molecules. These complexes offered the

possibility of using up some of the spare capacity of the plant.

The first target molecule was the acylated derivative of fiuoroben.zene, with

the acyl group in either the ortho- or the para- positions. The reason behind the work

was to find an alternative catalyst to aluminium chloride because of environmental

considerations.

COCH3 COCH3

ortho para

Scheme 2.1.2.1: Ortho - and para- acylated fluorobenzene

The aim was to synthesise this molecule by inserting an acyl group into

fluourobenzene by the use of a bidentate N-N Pd complex. This meant progressing

the previous work from simple alkenes, and investigating its usefulness with regard to

aromatics, specifically fluorobenzene.

56

CM3 oC,

CJN/\X O

O.CH3

F

acylated fluorobenzer

COCH '-r "Pd" (NV \ MeCN

AgOTf

OTf -

+

OTf -

CO-1/ NaX

Chapter Two

1+ r CH3

I ' Pd OTf

I

, \ AgOTf,Q{, LO' F U 7 7

Scheme 2.1.2.2: Insertion of fluorobenzene into the complex (bpy)Pd(COCH 3)(I)

If this inserted acyl complex could be made, it is postulated that it may be

possible to separate the 'acylated' fluorobenzene and set up a catalytic cycle,

regenerating the Pd complex for further reaction, with the complex becoming a

catalytic reagent.

Scheme 2.1.2.3: Catalytic cycle for the production of acylated fluorobenzene

57

Chapter Two

In the first stage of the reaction the fiuorobenzene inserts into the Pd-acyl

bond forming a five membered metallocycle with the palladium. The complex would

then undergo a further CO insertion, before the acylated fiuorobenzene is separated,

and the catalyst regenerated. This proposal results in the formation of acylated

fiuorobenzene catalysed by the complex {(bpy)Pd(COCH3)(I)}.

The second of the target molecules was the 4-4 'difiuorobenzophenone shown

below in figure 2.1.2.1.

a I F"

II

Figure 2.1.2.1: 4,4'-difluorobenzophenone

This molecule is currently synthesised by Laporte using fiuorobenzene and

phosgene in the reaction shown below.

0 F F

+ cIcI F

4,4 70%

4,2 15%

4,3 10%

Scheme 2.1.2.4: Synthesis of difluorobenzophenone

Chapter Two

The main drawback with the reaction is that it is not stereospecific. The yield

of 4-4'difluorobenzophenone is 70%, and the remaining 30% of the products are of

little use to the chemical industry. Laporte currently manufacture and sell 700 tonnes

per annum of the 4-4' difluorobenzophenone to polymer manufacturers to synthesise

the polymer Victrex (PEEK).

1 II

F)C 1OF 0 n

VICTREX (PEEK)

Scheme 2.1.2.5: The reaction of 4-4' difluorobenzphenone to produce the polymer Victrex

Zeneca wanted to be able to make the starting material, 4-4'

difluorobenzophenone for £10-12 per kg, thus undercutting the Laporte price of

£20/kg. This would give them the option of making it themselves, or selling the

technology to Laporte with a tie in deal to buy the fluorobenzene exclusively from

them.

The palladium complex{(bpy)Pd(COCH3)(I)} is also postulated to be a

catalyst in the synthesis of the polymer PEK. The proposed synthetic route is shown

below in Scheme 2.1.2.6. The starting material for the synthesis is

(bpy)Pd(CODPE)(I), which is converted as before to the ionic complex

{(bpy)Pd(CODPE)(CH 3CN)}OTf This complex is then reacted alternately with DPE

and CO to build up the polymer PEK.

59

Chapter Two

N. CODPE

NI I + cao DPE

MCCN! AgOTf

1+ DPE

o c/

I OTC

N/

N

NaX

1+

1 0 0 OTf I ii

N ,C)LDpEl o nPd

[

N"

% X

j

PEK

Scheme 2.1.2.6: Potential use of a Palladium complex to produce the polymer PEK

2.2 Reactions of (bpy)Pd(COMe)(I) with Cyclic Alkenes and Dienes

A dichioromethane solution of (bpy)Pd(COMe)(I) was cooled to 0 °C. To the

solution was added acetonitrile, silver triflate, and cyclic alkene or diene, and a yellow

solid of silver iodide immediately precipitated out of solution. The solution was stirred

for three hours before being filtered, and the solvent removed under vacuum. The

product was identified on the basis of mass spectrum and IR.

Me

Chapter Two

Results and Discussion

In Table 2.2.1 the relevant spectroscopic data is shown.

Cyclic Diene or Alkene Product MS/amu ER (CO)/ cm'

Cyclohexene { (bpy)Pd(C6H1 000Me) }(OTf), 1 M = 387 1690

1,3-cyclóhexadiene {(bpy)Pd(C6H8COMe))(OTf), 2 M = 385 1682

1,4-cyclohexadiene {(bpy)Pd(C6H8COMe)}(OTf), 3 M 385 1656

1,5-cyclooctadiene {(bpy)Pd(C6H12COMe)}(OTf), 4 M = 389 1654

Table 2.2.1: Spectroscopic data for acyl inserted Pd complexes

All of the products were identified on the basis of their mass spectra, which all

showed the parent ion peak at the expected value. The resultant complexes are shown

below in figure 2.2.1

/ CH3

IN\ Pd

oC

{(bpy)Pd(C 6H8COMe)) 0T1 3

+ _+ CR3

OTF OTf

flPd

{(bpy)Pd(C 6H8COMe)}OTf 2

CH3 O '

N C OTF

N / [ 'Pd

'

{(bpy)Pd(C 8HCOMe)} OTf 4

IN\ Pd

o C/ CR3

{(bpy)Pd(C 6HCOMe)} OTf 1

+

OTf

Figure 2.2.1: The complexes from in the reaction with { (bpy)Pd(COCH3)(CH3 CN) }OTf

61

Chapter Two

The complexes are all unstable in the presence of an inert gas. This contrasts

with previous work with the alkenes norbornene and dicyclopentadiene, where the

complexes have been described as being stable in air for several days at room

temperature. 9 In this case all the solutions begin to turn black upon addition of the

alkene or diene. The black colour comes from elemental palladium precipitating out of

solution. The JR shows the presence of a peak for the COCH3 peak at around 1600-

1 700cm', indicating that the desired complexes have been formed.

The solutions were left to stir for several days until all the elemental palladium

precipitated out of the solution. The solution was filtered and reduced under vacuum,

leaving no evidence of any of the desired complexes being formed.

Conclusion

The complex (bpy)Pd(COCH3)(I) will react with cyclic alkenes and dienes to

form the resultant acyl inserted complexes. These complexes however, are

unexpectedly unstable, even in the presence of an inert gas. The complexes are

probably unstable due to the five membered metallocycle of the alkene or diene. This

part of the complex is physically strained making it unstable, and this instability

probably results in the whole complex falling apart.

2.3 Reactions Of (bpy)Pd(COMe)(I) with Arenes

A dichloromethane solution of (bpy)Pd(COMe)(I) was cooled to 0 °C. To the

solution was added acetonitrile, silver trifiate, and cyclic alkene or diene, and a yellow

solid of silver iodide immediately precipitated out of solution. The solution was stirred

62

Chapter Two

for three hours before being filtered, and the solvent removed under vacuum. The

products were analysed for their Mass Spectra and 1W.


Below in figure 2.3.1 are shown the complexes that were hoped to be

synthesised by this route.

CH3 oc,

IN le ~~b

+ I CH3 OTf Oc/

Pd I rN I I

LN

+

OTf -

{(bpyPd(C 6H6COMe)}OTf 5

Oc/ CH3 oTF

IN ,Pd B

{(bpy)Pd(C 6H3rCOMe)) 0T1 7

r CH3 OTf I o"

I N / IN\ Pd

H3j

{(bpy)Pd(C 6H5MCCOMe)} 0T1 9

((bpy)Pd(C 6H5FCOMe)} OTf 6

{(bpy)Pd(C 8H8COMe)} OTf 8

CH3 i r N

O' OTf / 0H

IN.' \ I HO

{(bpyC6H4(OH)2COMC)} OTt 10

+

OTF

Figure 2.3.1: The expected complexes from the reaction with {(bpy)Pd(COCH3)(CH3CN)}OTf

63

Chapter Two

In the case of the above complexes there is no evidence of their formation in

either the IR spectrum or in terms of mass spectroscopy. There are no peaks at the

expected range of 1600-1700cm' for the IR, and their is no evidence of any parent

ion peak in the mass spectrum.

In each of the reactions there is a large degree of decomposition with

elemental palladium precipitating out of solution. The decomposition in these

reactions also happens more quickly than in the reactions with the alkenes and the

cyclic dienes, making analysis difficult. These complexes are expected to be much

harder to form than the alkene type complexes because of the strength of the aromatic

C-C bond..

Conclusion

There is no evidence for the formation of the desired palladium complexes

with arene rings. The strength of the aromatic C-C bond appears to be prevent the

acyl insertion. This part of the work was the least likely to be successful as this type of

insertion into an arene ring is not a known reaction. However, after finding evidence

for the formation of the alkene and diene complexes it was attempted with the

industrial aim of the thesis in mind.

2.4 Reaction of (tmeda)PdCl 2 with Phenyl Lithium

A solution of (tmeda)PdC1 2 suspended in diethyl ether was cooled to -30T

using an acetone/CO 2 bath. The stirred solution was treated with PhLi and was

allowed to warm slowly to 0°C. The resultant solution was stirred for 1 hour, before

ice cold water (lOml) was added. The organic layer was separated and dried over

MgSO4, and the solvent was removed under vacuum. The product was identified as

the starting material (tmeda)PdC1 2 on the basis of 'H nmr and mass spectra.

64

Chapter Two

Results And Discussion

H 5/ppm

2x -N(CH3)2 2.54 (s, 6)

2x -CH2- 2.26 (s, 4)

Table 2.4.1: The NMR results of the reaction

In the 'H NMR the appearance of only two peaks indicates that the starting

material, (tmeda)Pd(Cl)2, has been formed. This is confirmed by the mass spectra

which has a parent ion peak at 291amu.

The aim of the reaction was to synthesise the complex (tmeda)PdPh 2, 11,

which could then be reacted with CO to produce benzophenone as shown below in

scheme 2.4.1

N Ph %% / Co Pd

'Ph Ph-Ph

Scheme 2.4.1: The reaction of (tmeda)Pd(Ph)2 to produce benzophenone, palladium, and tmeda

Previous work by De Graaf et. al. 8 has shown that the similar complex

(tmeda)PdMe2 would undergo a reaction with CO. yielding acetone, tmeda, and

palladium.

65

Chapter Two

1—N /CH3 d6-benzene I /Pd\

l LN CH3

eqCO

0 II + Pd + tmeda

CH3CH3

tmeda

Scheme 2.4.2: Reaction of (tmeda)Pd(CH 3)2 to produce acetone, palladium, and tmeda

The reaction was undertaken in d 6-benzene, and the aim was to attempt to

repeat the reaction with two phenyl groups instead of the two methyl groups. If the

reaction was possible, it may then have been possible to attempt the reaction with a

stereospecific lithium para-fluorobenzene, making the reaction generate the desired

target complex 4-4' difluorobenzophenone.

rN Cl

I Pd + LN Cl

Li

F

F

10 [Pd

N / \

0 F

11

[Pd Co

IN

FF + Pd + tmeda

Scheme 2.4.3: Possible synthetic route for the synthesis of 4-4'diflnorobenzophenone

Chapter Two

The data form the 1H nmr and the mass spectra indicate that attempts to form

the complex (bpy)Pd(Ph)2 have failed, with only the starting material evident in the

analysis. This failure is most likely explained by the large size and steric bulk of the

two phenyl ligands making it impossible for both to occupy cis positions around the

palladium metal.

Conclusion

It is not possible to form the complex (bpy)Pd(Ph)2 as a possible reactant to

produce benzophenone. The steric bulk of the arene ring prevents its formation.

2.5 Conclusion

The complex (bpy)Pd(COCH3)(I) has been shown to react with simple cyclic

alkenes extending previous work with simple alkenes. The work however was not

able to be further extended into allowing the complexes to react with benzene and

substituted benzenes. This meant that the industrial aim of the project of setting up a

catalytic cycle producing an acylated fluorobenzene, and regenerating the palladium

complex (bpy)Pd(COCH 3)(X), were not able to be achieved

Attempts to synthesise the second industrial target molecule 4,4'-

difluorobenzophenone also failed. The proposed synthetic route via the complex

(bpy)Pd(C6H4F)2 was not possible as the steric bulk of a phenyl ring is too large to

occupy the cis positions on the Pd metal centre.

67

Chapter Two

2.6 References

W. Reppe, A. Magin, US Patent 2,577,208 (1951)

A. Sen, T.-W. Lai, J. Am. Chem. Soc., 1982, 104, 3520

A. Sen, T.-W. Lai, Organometallics, 1984, 3, 866

J.S. Brumbaugh, R.R. Whittle, M. Parvez, A. Sen, Organomelallics, 1990, 9, 1735

J.P. Coilman, L.S. Hegedus, J.R. Norton, R.G. Finke, Principles andApplications of Organotransition Metal Chemistry, University Science Books, Mill Valley, CA, 1987

G.P.C.M. Dekker, C.J. Elsevier, K. Vrieze, P.W.N.H. van Leeuewen, Organometallics, 1992, 11, 1598

G.P.C.M. Dekker, C.J. Elsevier, K. Vrieze, P.W.N.H. van Leeuewen, CT Roobeek, .J. Organomet. Chem., 1992, 430, 357

W. de Graaf, J. Boersma, W.J.J. Smeets, A.L. Spek, G. van Koten, Organomelallics, 1989, 8, 2907

W. de Graaf, J. Boersma, G. van Koten, Organometallics, 1990, 9, 1479

B.A. Markies, M.H.P. Rietveld, J. Boersma, A.L. Spek, G. van Koten, J. Organomet. Chem., 1992, 424, C12

B.A. Markies, M.H.P. Rietveld, J. Boersma, A.L. Spek, G. van Koten, K.A.N Verkerk, H. Kooij man, .1. Chem. Soc., Chem. Comm., 1993, 1317

Chapter Three

Chapter Three

3.1 Introduction

In chapter one the bonding of a benzene ring to an Os or Ru three atom

cluster in the face capping and apical modes was discussed. A benzene, or more

generally an arene, can also bond to a cluster in the benzyne bonding mode.

C(114) C(115)

Q116)

C(111) 0003)

Ci

0(23) __-- C(33,1 CL 0(21)

C(23) -

=IO(C3(

) 0(13)

C(

Figure 3.1.1: Crystal structure of 0s 3(CO)9(H)2(C6H4)

In the above structure the benzene is bonded to the cluster through two of the

ring carbons. The benzene is bound through two a bonds and one it bond, over the

face of the cluster. The ring is at an angle of between 63.9° from the plane of the

cluster. The ligand is a four electron donor, donating one electron each to Os(1) and

Os(2) via the two a bonds, and two electrons to Os(3) via the it bond.

This type of cluster was first synthesised by Deeming and Underhill (2) directly

from the reaction of 0s3(CO)12 with benzene at 200 °C. More recently clusters of the

type Os3(CO)(L)(,.13:i1 2 :i12 :112-C6H) have been shown to undergo conversion to the

benzyne complexes of the type

We

Chapter Three

The Os(1)-Os(2) distance is long, 3.026(2)A, considering that a metal-metal

bond is present, and it is very similar to the Os-Os bond in the complex

0s3(C0) 10(0Me)2 This cluster has two -OMe bridges and the Os-Os distance of

3.078(2)A is for a formal bond order of zero. 4

The fragment 0s(1)(.t-H)C(1 1 1)C(1 12)0s(2) is best considered as a

delocalised bonding unit.

C C

/ \ Oszr------Os

Figure 3.1.2: The delocalised bonding unit OsQ.-H)CCOs

Bridging metal hydrides, in the absence of other bridging groups, usually result

in the M-M bond being lengthened." When a second bridging group, with a single

bridgehead atom is added, the M-M bond is usually found to be shortened. (' ) If the

second bridging group has two bridgehead atoms the shortening effect is less

pronounced, as in the case of the cluster Os 3(t-H)(CO) io(C3H3N2). 7

(CO),

(CO)3 OS OS (CO)3

f c N H

Figure 3.1.3: The bonding mode of Os3(1.-H)(CO) 1 o(C3H3N2)

In the benzyne cluster there is no shortening effect, and instead a lengthening of

0.05A is observed, when compared to the hydride bridged Os-Os bond of 2.989(1)A

in the cluster 0s3(9-H)2(C0)10. 8

70

Chapter Three

The benzyne ligand is able to adapt to span various metal-metal edges in

cluster species. The Os-Os bond length of 3.791(1)A in the cluster H0s3(C0)9Q.t-

H)-SMe)(C614) 9 represents the Os-Os bond which is bridged by the benzyne and

the -SMe group. The thiol group is a three electron donor, and this causes the Os-Os

bond to lengthen.

0 Os— -H

/7 \I

Me

Figure 3.1.4: The bonding mode of 0s 3(C0)9(4-H)(j.t-SMe)(C 6H4)

The Os-Os bond length of 2.866(2)A in the benzyne cluster

0s3(C0)9(H)2(C61Q is bridged by a hydride, but is slightly shorter than the Os-Os

distance .of 2.877(3)A in the parent cluster, 0s 3(C0) 12 .' 8 This suggests that the it

interaction of the benzyne ligand on Os(3) has a shortening effect on the Os-Os

distance. A similar influence appears on the unbridged Os(2)-Os(3) bond which, is

shortened by around 0.03A compared to the parent cluster 0s 3(CO) 12 .

In their paper Johnson et al also reported the synthesis of aryne clusters in

which the ligands used were substituted benzenes such as toluene. ( ' ) The substituted

aryne clusters are thought to exist in four different isomeric forms.

71

Chapter Three

R

r\R

Os-- H

__ / \ i Os-Os

a

R

R R//\\ f

1' 8

Figure 3.1.5: Four isomeric forms of 0s 3(CO)9(H)2(C6H3R)

The first proposals were that the isomers resulted from a ring flipping

mechanism which is occurring rapidly on the NMR timescale at room temperature.

The mechanism was also postulated as possible exchange between two different

forms, i.e. a exchanging with y, and 0 exchanging with 6. This means that the ring is

in a fixed position, and that it is the hydrides that are exchanging, resulting in only two

isomeric forms."

'H NMR studies carried out by Shapely and Kneuper' ° using spin saturation

techniques have led to the postulation that the hydrides on the cluster are fluxional,

and also exchange with those on the benzene ring.

72

Chapter Three

Figure 3.1.6: Exchange mechanism of hydride and arene proton

In the proposed exchange mechanism the bridging hydride moves from a site

bridging a pair of Os atoms to a site associated with a pair of electrons between a C

and an Os atom. This creates an agostic three centre two electron bond of C-H-Os.

The arene ligand then rolls so that a new C-H-Os bridge is created while the other is

broken. Exchange is completed by proton migration back to the Os-Os site creating a

new Os-H-Os bridge. Some it bonding or interaction between the aryl and the Os

framework is maintained throughout the reaction.

73

Chapter Three

3.2 Reactions of 0s3(C0), 0(MeCN)2 with Substituted Arenes

Following on from the work of Johnson et al,' a series of substituted benzene

aryne complexes were synthesised and their crystal structures investigated.

3.2.1 Reaction of 0s 3(C0),0(MeCN)2 with Arenes of the Type C 6115R (where R =

F, Cl, Br, and CR3)

An arene solution of 0s3(CO),o(MeCN)2 (13) was heated under reflux for 1

hour before being left to cool to room temperature. The solution changed from yellow

to dark brown after reflux. The arene was removed under vacuum and three main

products were separated chromatographically using hexane as eluant. In order of

elution these products were identified as unreacted cluster 0s 3(CO),o(MeCN)2 (13),

0s3 (CO) 12 (12), and 0s3(C0)9(t-H)2(C6H3R) (14, 15, and 17) and 0s3(C0), o(p.-Br) 2

(16), on the basis of IR, mass spectrometry, and in addition for 14, 15, and 17 by 'H

NMIR. All four products were confirmed by X-ray crystallography.


JR and Mass Spectroscopy

In each case the unreacted cluster 13 and the parent cluster 12 were identified

on the basis of their IR spectra in the carbonyl stretching region, and their mass

spectra. The unreacted cluster 13 was present in 10-15% yield. Clusters 14, 15, 16,

and 17 were characterised on the basis of their mass spectra which showed the parent

ion peaks at the expected positions, followed by the subsequent loss of carbonyl

ligands. The IR spectra showed peaks in the region 2100-1970 cm' indicating that

only terminal carbonyls are present. The data are shown over the page in table

3.2.1.1.

74

Chapter Three

0s3(C0) 9(p-ll)2(C6H3F), 14

IR (vCO)I cm"

2114, 2083, 2056, 2035, 2021, 2007, 2000

MS/amu

M' = 920 (caic. 918)

0s3(C0)9(p.-H)2 (C6H3CI) 1 15

IR (vCO)I cm'

2110, 2083, 2058, 2037, 2025, 2025, 2011, 2003

MS/amu

M' = 936 (caic. 934)

0s3(C0) 10(J.L-Br)2, 16

ER (vCO)/ cm'

2113, 2082, 2053, 2014, 2007

MS/amu

M+ = 1012 (calc. 1008)

0s3(CO)9(p.-R)2(C6113C113), 17

JR (vCO)I cm 1

2109, 2079, 2052, 2033, 2022, 2002

MS/amu

M' = 918 (caic. 914)

Table 3.2.1.1: Spectroscopic data for the aryl cluster species

Cluster 16 was an attempted synthesis of the cluster Os 3(CO)9(.t-H) 2(C6H3Br),

but the IR spectrum showed no expected peak at 2035 cm 1 , as in the case of the

fluoro- and chlorobenzene derivatives. There was also an additional peak at 2053

cm'. In the mass spectrum the parent peak was thought to be M= 984 (caic. 984)

amu which indicated the desired product. However a smaller peak at M= 1012 (caic

1010) amu can be attributed to the parent peak of cluster 16, making the peak at 984

amu the peak for 16 with the loss of one carbonyl. The 'H NMR was recorded in

CD2C12 but gave only the signal for free bromobenzene. This evidence along with

crystallographic information proved that the cluster was in fact 0s 3(C0), o(.t-Br)2."

Os—Br OS•__Br___OS

Figure 3.2.1.1: The bonding mode of 0s3(CO) 1o(-Br) 2

75

Chapter Three

'H NMR

The 'H NUR of the remaining three clusters were measured in CDCI 3, and the

results are shown below.

Hb Mc Hb Mc

sHd Hd

Hd Hd

Ic

flu

14 15 15

0s3(CO) 9(1i-R)2 (C6H3F), 14 Os3(CO)9(i-H)2(C6H3CI), 15

H 6/ppm 11 8/PPM

Ha 7.63 (d) Ha 7.83 (d), 7.89 (d)

Hb 6.58 (t) Rb 6.82 (t)

Hc 6.94 (m) Hc 7.30 (d)

Hd -18.3 (s) Hd -18.7(s)

Figure 3.2.1.2: The clusters Os 3(CO) 9(pt-H)2(C6H3F) and Os 3(CO)9(-H)2(C6H3Cl) and a table of

their 'H NMR data

For cluster 14, four resonances were observed at ö values of 7.63 (1H), 6.94

(1H), 6.58 (1H), and -18.3 (2H) ppm. These resonances can be readily assigned to the

hydrogens on the fluorobenzene as shown in the diagram, and the data suggests that

the cluster exists in one isomeric form, with the F-atom occupying the site nearest to

the cluster.

The 'H NMR of cluster 15 indicates the presence of two isomers with the

observation of five resonances at 5 values 7.89 (1H), 7.83(1H), 7.30 (IH), 6.82(1H),

76

Chapter Three

The 'H NM1R of cluster 15 indicates the presence of two isomers with the

observation of five resonances at ö values 7.89 (1H), 7.83(1H), 7.30 (1H), 6.82(1H),

and -18.7 (211) ppm. The signals are assigned to the hydrogens as shown in the

diagram with the predominate isomer being the one where the -Cl atom occupies the

site nearest to the cluster, as in the case with 14.

In figure 3.2.1.3 below is the 'H NUR data for the for cluster 17.

Ha Ha

H s/ppm

Ha 7.74 (d) 7.84 (d)

Hb 6.73 (m) 6.73 (dd)

Hc 7.08 (d) 7.71 (s)

Hd 2.45 (s) 2.31 (s)

He -18.5(s) -18.9(s)

Figure 3.2.1.3: The two isomeric forms of the cluster 0s 3 (CO)9(4-H)2(C6H3CH3) and its 'H NMR

data

The 'H NMIR data for 17 indicates the presence of two isomers with the

observation of eight resonances at ö values 7.84 (111), 7.74 (1H), 7.71 (111), 7.08

(111), 6.73 (1H), 2.45 (3H), 2.31 (3H), -18.5 (2H), and -18.9 (2H) ppm. The signals

have been assigned above, and the ratio of isomers is approximately 1:4.

The observation of a single hydride resonance in each of the three spectra

implies that the hydrides are fluxional in all the complexes.

77

Chapter Three

X-ray Structure Determination

Single crystals of 0s 3(C0)9(.t-H)2(C6H3F) 14, 0s3(C0)9(t-H)2(C6H3C1) 15,

and 0s3(C0)9(t-H) 2(C6H3CH3) 17, suitable for X-ray analysis were grown from a

solution of pentane at 5 °C. The solid state molecular structures are presented in the

following pages together with some relevant bond lengths for each structure. In each

case the structure confirms that the Os trinuclear cluster framework remains intact,

and that the arene ligand is aryne bonded to the cluster framework. The carbonyls are

all terminally bound, as indicated by the IR spectrum, with three attached to each Os

atom.

A single crystal of 0s3(C0) io(t-Br)2 was also grown from a solution of

pentane at 5 T. The structure was not solved as it has been reported previously."

78

0(23) 0(31)

0(33)

0(22]

L.flupwr inre

Figure 3.2.1.4: The molecular structure for Os 3(CO) 9(-H)2(C6H3F)

Os(1)-Os(2) 2.7554(8)

Os(1)-Os(3) 2.8615(7)

Os(2)-Os(3) 3.0417(8)

Os(3)-C(2) 2.14(2)

Os(2)-C(1) 2.11(2)

Os(1)-C(1) 2.400(13)

Os(1)-C(2) 2.358(13)

C(1)-C(6) 1.42(2)

C(1)-C(2) 1.48(2)

C(2)-C(3) 1.41(2)

C(3)-C(4) 1.36(3)

C(4)-C(5) 1.41(3)

C(5)-C(6) 1.37(3)

C(1)-F(1) 1.36(2)

mean C-0 1.14

Table 3.2.1.2: Selected bond lengths for Os 3(CO)9(-H)2(C6H3F)

79

031

Chapter Three

013

Figure 3.2.1.5: Molecular structure of Os 3(CO)9(-H)2(C6H3Cl)

Os(1)-Os(2) 2.7502(13)

Os(1)-Os(3) 3.010(2)

Os(2)-Os(3) 2.852(2)

Os(1)-C(6) 2.102(11)

Os(3)-C(5) 2.152(11)

Os(2)-C(6) 2.439(11)

Os(2)-C(5) 2.298(11)

C(5)-C(6) 1.42(2)

C(1)-C(2) 1.32(2)

C(2)-C(3) 1.41(2)

C(3)-C(4) 1.37(2)

C(4)-C(5) 1.42(2)

C(1)-C(6) 1.43(2)

C(1)-Cl(1) 1.780(12)

mean C-0 1.14

Table 3.2.1.3: Selected bond lengths (A) for 0s3(CO)g(i.t-H)2(C6H30)

80

(13)

Chapter Three

Figure 3.2.1.6: Molecular structure of 0s3(CO)9()i-H)2{ C6H 3(CH3)}

Os(1)-Os(2) 2.8470(10)

Os(1)-Os(3) 3.0147(9)

Os(2)-Os(3) 2.7627(9)

Os(1)-C(76) 2.11(2)

Os(3)-C(71) 2.13(2)

Os(2)-C(71) 2.432(14)

Os(2)-C(76) 2.27(2)

C(71)-C(76) 1.36(2)

C(71)-C(72) 1.46(2)

C(72)-C(73) 1.35(2)

C(73)-C(74) 1.45(2)

C(74)-C(75) 1.36(2)

C(75)-C(76) 1.47(2)

C(73)-C(77) 1.50(2)

mean C-0 1.14

Table 3.2.1.4: Selected bond lengths (A) for Os3(CO)9(p.-H)2C6H3(CH3))

81

Chapter Three

3.2.2 Reaction of 0s 3(CO),o(MeCN)2 with C6114(CH3)2 (ortho-, meta-, and para-)

The reaction conditions utilised were as described previously, using an ortho-,

meta-, or para-xylene solution of 0s 3(CO), o(MeCN)2. For ortho- and meta-xylene,

three products were separated by TLC using hexane as eluant, and these were

identified as the unreacted cluster 13, cluster 12, and Os 3(CO)9(t-H)2 {C6H2(CH3)2}

18 and 19, on the basis of IR, mass spectrometry, 'H NMR, and X-ray

crystallography. For the para-xylene reaction two major products were separated by

TLC using hexane as eluent, and these were identified as unreacted cluster 13, and

cluster 12.


The unreacted cluster 13 and the parent cluster 12 were identified on the basis

of their IR carbonyl spectra, and their mass spectrometry. Clusters 18 and 19 were

characterised on the basis of their mass spectra which showed the parent ion peaks at

the expected values, followed by subsequent loss of carbonyl ligands. The IR

spectrum shows peaks in the region of 2100-1970 cm' indicating that only terminal

carbonyls are present. The 'H NMIR spectra were recorded in CDC1 3, and all the

spectroscopic data is shown below in figure 3.2.2.1.

U

Os3(CO),(H)2 {orth0CH2(CH3)2} 0s3(C0)9(1)2 {metaC 6H2(CH3)2 )

Figure 3.2.2.1: The bonding modes of the clusters Os 3(CO)9(-H)2 {ortho-C6H2(CH3)2} and

0s3(C0)9(-H)2{meta-C6H2(CH3)2}

82

Chapter Three

Os3(CO)9(-H)2 {ortho-C6II2(CH3)2}, 18

ER (vCO)Icm'

2107, 2079, 2053, 2033, 2022, 2006, 1997

MS/amu

M+ 930 (ca1c. 928)

1H NMR 6/ppm

Ha: 7.60 (s), Hb: 2.19 (s), Hc: -18.1 (s)

Os3(CO)9(-H)2 meta-C61I2(CH3)2), 19

IR (vCO)/cm'

2105, 2076, 2052, 2032, 2021, 2005, 1997

MS/amu

M = 932 (ca1c. 928)

'H NMR 6/ppm

Ha: 7.43 (s), Hb: 6.80 (s), Hc: 2.17 (s), Hd: 2.19 (s), He: -18.5 (s)

Table 3.2.2.1: The spectroscopic data for Os3 (CO)9(-H)2 {ortho-C6H2(CH3)2} and Os 3(CO)9(.t-

H)2{meta-C6H2(CH3)2}, and their spectroscopic data

The 'H NIvIR of 18 indicates the presence of a single isomer with the observation of

four resonances at ö values 7.60 (2H), 2.19 (6H), and -18.5 (2H).

The 'H NMR of 19 indicates the presence of one isomer with the observation

of five resonances at 6 values 7.43 (1H), 6.80 (1H), 2.19 (3H), 2.17 (3H), and -18.5

(2H) ppm.

The unreacted cluster 13 and the parent cluster 12 were identified on the basis

of their IR carbonyl spectra, and their mass spectrometry. There is no evidence for the

desired product Os 3(CO)9(.t-H)2{C6H2(CH3)2}, as shown in figure 31.2.2.

83

Chapter Three

Figure 3.2.2.2: The structure of 0s 3(C0) 9(-H)2(C6H2(CH3)2 ).

It appears that the product cannot be formed because of the steric interaction

of the two -CH3 groups with the Os cluster. Previously it has been shown, in the case

of meta-xylene, that one -CH 3 group can occupy the site closest to the cluster.

However in this case in which two -CH 3 groups would need to occupy these

positions, and the steric interaction appears to be too great.

X-ray Structure Determination

Single crystals of ortho- and meta- Os3(CO)9(..t-H)2 {C6H3(CH3)2) 18 and 19,

suitable for X-ray analysis were grown solutions of pentane at 5 °C. The solid state

molecular structure is presented together with some relevant bond lengths for each

structure. The structure confirms that the Os trinuclear cluster framework remains

intact, and that both the xylenes are aryne bonded to the cluster framework. The

carbonyls are all terminally bound, as indicated by the IR spectrum, with three

attached to each Os atom.

84

Chapter Three

031

021

Figure 3.2.2.3: Molecular structure of 0s3(CO)9(9-H)2{C6H2(CH3)2 }

Os(1)-Os(2) 2.766(3) I Os(1)-C(6) 2.38(2)

Os(1)-Os(3) 2.881(4)

Os(2)-Os(3) 3.056(3)

Os(2)-C(1) 2.10(2)

Os(3)-C(6) 2.12(2)

Os(1)-C(1) 2.30(2)

C(1)-C(6) 1.43(3)

C(1)-C(2) 1.44(3)

C(2)-C(3) 1.37(3)

C(3)-C(4) 1.40(3)

I C(4)-C(5) 1.37(3)

C(5)-c(6) 1.47(3)

C(3)-C(30) 1.55(3)

C(4)-C(40) 1.53(3)

mean CO 1.13

Table 3.2.2.2: Selected bond lengths (A) for Os3(CO)9(t-H)2[C6H2(CH3)2]

85

033

Chapter Three

021

Figure 3.2.2.4: Molecular structure of 0s3(CO)9(9-H)2 [C6H2(CH3)2]

Os(1)-Os(2) 2.7425(12)

Os(1)-Os(3) 2.8666(13)

Os(2)-Os(3) 3.0379(15)

Os(3)-C(1) 2.108(10)

Os(2)-C(2) 2.123(10)

Os(1)-C(1) 2.306(10)

Os(1)-C(2) 2.408(9)

C(1)-C(2) 1.441(14)

C(2)-C(3) 1.445(13)

C(3)-C(4) 1.39(2)

C(4)-C(5) 1.39(2)

C(5)-C(6) 1.368(15)

C(6)-C(1) 1.451(15)

C(3)-C(3M) 1.51(2)

C(5)-C(5M) 1.504(14)

mean C-O 1.13

Table 3.2.2.3: Selected bond lengths (A) for 0s3(CO)9(i.t-H)2[C6H2(CH3)2]

86

Chapter Three

3.2.3 Conclusion

From the spectroscopic and crystallographic data it can be observed that

different substituted benzenes yield different predominant isomers. The fluoro- and

chlorobenzenes yield species where the halogen occupies the site closest to the Os

cluster, i.e. the most steric hindered site. Previous studies by Deeming and Arce (12) on

the cluster { Os 3H(CO)9(AsMe2)(C6H3OMe) } have indicated that the the orientation

of the benzyne ligand is dependent on electronic effects. As the halogens are electron

donating they favour adopting the position nearest to the cluster because of the

conjugative effect on the benzyne ring. If the halogen occupies the site furthest away

there is unfavourable competition between the halogen and the metal for the benzyne

LUMO that is involved in it-bonding between the Os atom and the benzyne ligand.

When the substituted benzenes contain -CH 3 groups, the preferred site is the least

sterically hindered site, which is that furthest away from the Os cluster. A single -CH 3

group will, however, occupy the site closest to the cluster as in the reaction with

meta-xylene, but two -CH 3 groups will not occupy these sites simultaneously, as

shown in the unsuccessful reaction with para-xylene. This position of a -CH 3 group is

probably a combination of both electronic and steric effects.

A summary of the relevant bond lengths in the five structures are shown below

in table 3.2.3.1.

Chapter Three

Cluster Number -

Bond Description 14 15 17 18 19

AvOs-Os 2.87 2.87 2.87 2.90 2.88

Max Os-Os 3.042 3.010 3.014 3.056 3.038

Mm Os-Os 2.756 2.750 2.763 2.766 2.743

Av ring C-C 1.39 1.39 1.41 1.41 1.41

Max ring C-C 1.49 1.43 1.47 1.47 1.45

Nfin ring c-c 1.34 1.32 1.35 1.37 1.37

C-R 1.396 1.78 1.36 1.55, 1.53 1.50, 1.51

a-Os-C 2.11, 2.14 2.10, 2.15 2.11, 2.13 2.10, 2.12 2.11, 2.12

t-Os-C 2.36, 2.41 2.30, 2.44 2.27, 2.43 2.30, 2.38 2.31, 2.41

Ày c-o 1.14 1.14 1.14 1.13 1.13

Table 3.2.3.1: Summary of bond distances of the five crystal structures

In the crystal structures there is no great variation in the bond lengths between

the different structures. The average Os-Os distances are all in the range 2.87-2.90 A.

Each structure has one long and one short Os-Os bond, with the short bond being the

one which is bridged by the aryne ligand in the a-bonded manner. This bond is also

bridged by a hydride, and as demonstrated in the introduction, this exerts a shortening

effect on the Os-Os bond. The longest bond in each case is the one which has a

bridging hydride only, causing the bond to lengthen to 3.01-3.06 A. In each case this

means that the cluster is slightly distorted, and this is reflected in the ic-Os-C bonds. In

each structure one is longer than the other by 8-16 A. From structure to structure

there is a slight variation in the average length of the ic-bonds, which are slightly

longer at an average of 2.38 A for the halobenzenes than the average of 2.35 A for the

methylbenzenes. The a-Os-C bonds are more equal in value, with only a slight

differences in each structure.

The arene rings all have an average C-C bond length of 1.39 to 1.41 A. This

compares almost exactly to the bond length in free benzene of 1.396 A. The average

Chapter Three

C-C distances in the arene rings are slightly shorter at 1.395 A in the halobenzenes

than they are in the methylbenzenes at 1.41 A. The C-C bond lengths vary in each

structure from that approaching a C-C double bond to a C-C single bond. In four of

the structures C-C bond bridging the cluster is one of the longest, except in the case

Of Os3(CO)9(4-H)2 {C6H3(CH3)} (17) where the bridging C-C bond is short at 1.36(2)

A.

In each structure the C-R bond lengths are the normal bond lengths expected

for each structure. The average carbonyl bonds are almost identical in each structure

at 1.13-1.14 A.

In all the structures the hydride ligands were not located directly. In some the

XHYDEX programme was used to place the ligands, and in the others their position

can be determined by examination of the bond lengths.

3.3 Reactions of 0s3(C0) 10(MeCN)2 with ct-methylstyrene, Styrene, and 1,3

diisopropenebenzene

An octane solution of 0s3(CO) io(MeCN)2 (13) and the arene complex was

heated under refiux for 1 hour before being left to cool to room temperature. The

solvent was removed under vacuum and the products were separated

chromatographically by TLC using hexane as eluent.

3.3.1 Results and Discussion for Reaction with a-methylstyrene

Four main products were separated in the reaction and these wee identified as

unreacted cluster 13, cluster 12, and Os3(CO)9(.t-H)2[C 6H3(C(CH3)CH2)] 21 and 22,

Chapter Three.

by their IR and mass spectra. The unreacted cluster (13) and the parent cluster (12)

were identified on the basis of their JR spectra in the carbonyl stretching region and

their mass spectroscopy.

Compounds 21 and 22 both have similar IR spectra, and both have mass

spectra with parent ion peaks M= 941 (calc. 939) amu followed by subsequent loss

of carbonyls. This indicates that the products are very similar, and may be different

isomers of the same product. Previous work reported in this chapter has shown the

evidence for different isomers being formed, but these are not usually separable by

TLC. As the bands are very close on the TLC plate, clusters 21 and 22 may be two

different isomers of the product, as shown below in figure 3.3.1.1.

H2C

H C—CH3

H—?J5—H ,,CH

a b

Figure 3.3.1.1: The possible isomers of Os3(CO) 9(-H)2 [C6H3(C(CH3)CH2)]

Isomer a would appear to be the most likely to be formed as it is the least

sterically hindered of the two. As shown previously with toluene and the xylenes, a -

CH3 group will not occupy the site closest to the Os cluster in preference to a site

further away. This would be expected to exclude isomer b, but a possibility for its

formation is with the pendant arm parallel to the Os cluster. With the reactive

substituent in such a position it may be possible to form isomer b. As the yields are so

low the 'H NMR spectrum of the two species are too weak to assign peaks:

Me

Chapter Three

3.3.2 Results And Discussion Of Reaction with Styrene

Three products were separated by TLC using hexane as eluent. In order of

elution these products were identified as the unreacted cluster 13, cluster 12, and

Os3(CO)9(t-H)2 {C6H2(C6H3(CHCH2)) 23, on the basis of IR, mass spectrometry, and

in addition for 23, by 'H NMR.

Cluster 23 was characterised on the basis of its mass spectrum which showed

the parent ion peak at M= 926 (caic. 926) amu followed by subsequent loss of

carbonyl ligands. The JR spectrum shows peaks in the region 2100-1990 cm'

indicating that only terminal carbonyls are present. The compound may exist in the

isomers shown below.

H2C

Figure 3.3.2.1: Possible isomers of 0s 3(CO)g(j.t-H) 2 { C6H2(C6H3(CHCH2) )

The 'H NN'IR, which would be able to give structural details, is to weak to

assign because of the low yield of the cluster, but it does appear that the compound

has been formed.

91

Chapter Three

3.3.3 Results And Discussion Of Reaction with 1,3 diisopropenebenzene

Three products were separated by TLC using hexane as eluent. In order of

elution these products were identified as the unreacted cluster 13 and cluster 12 on

the basis of ER, and mass spectrometry.

The desired product with the 1,3 diisopropenylbenzene aryne bonded to the

cluster is not formed in the reaction. This is probably because of the steric interaction

of the pendant arm with the cluster.

H

Figure 3.3.3.1: A possible structure of 0s 3(C0)9(4-H)2 { C6H2(C(CH3)2) }

3.3.4 Conclusion

The evidence that the ct-methylstyrene product can exist as two isomers is not

supported by the non-reaction of the 1,3 diisopropenylbenzene with the Os cluster.

This reaction, although unsuccessful, indicates that the most likely products are those

shown below (Figure 3.3.4.1) where the reactive substituent occupies the site furthest

away from the metal cluster.

92

Chapter Three

H2C H C—H

H

H,C

Figure 3.3.4.1: Bonding modes of Os3 (CO) 9(-H)2 {C6H3(CHCH2)} and Os3(CO) 9(-

H)2 ( C6H3(C(CH3)CH2) }

With extremely low yields of the products, it has not been possible to obtain

any structural information from NMR, or from crystallography, although the products

do appear to have been formed.

93

Chapter Three

3.4 References

I.- R.J. Goudsmit, B.F.G. Johnson, J. Lewis, P.R. Raithby, M.J. Rosales, J. Chem. Soc., Dalton Trans., 1983, 2257

A. J. Deeming, M. Underhill, .1. Chem. Soc., Dalton Trans., 1974, 1415

M.A. Gallup, B.F.G. Johnson, J. Lewis, A. McCamley, R.N. Perutz, J. Chem. Soc., Chem. Comm., 1988, 1071

V.F. Allen, R. Mason, P.B. Hitchcock, J. Organomet. Chem., 1977, 140, 297

M.R. Churchill, B.G. DeBoer, F.J. Rotella, Inorg. Chem., 1976, 15, 1843

P.R. Raithby, Transition Metal Clusters, ed. B.F.G. Johnson, John Wiley and Sons, Chichester, 1980

J.R. Shapley, D.E. Samkofi C. Bueno, M.R. Churchill, Inorg. Chem., 1982, 21, 634

M.R. Churchill, B.G. DeBoer, Inorg. Chem., 1977, 16, 878

R.D. Adams, D. A. Katahira, L.-W. Yang, Organometallics, 1982, 1, 235

H.-J. Kneuper, J.R. Shapley, Organometallics, 1987, 6, 2455

B.F.G. Johnson, J. Lewis, P.A. Kilty, J. Chem. Soc., 1968, 2859

A.J.Arce, A.J. Deeming, .1. Chem. Soc., Dalton Trans., 1982, 1155

94

Chapter Four

Chapter Four

4.1 Introduction

In chapter three the synthesis of triosmium arene clusters with the arene

bonded in the benzyne mode were discussed. The benzyne cluster Os 3(CO)9(j-

H)2(C6H4), where the arene ring is bound to the metal cluster through two aromatic

carbons, is known to undergo subsequent reactions on both the arene ring, and on the

metal centre. Both types of reaction on the cluster Os 3(CO)9(j.t-H)2(C17l4) will be

discussed in this chapter. This type of work will then be extended later in the chapter

to deal with both types of reaction on the functionalised clusters 0s 3(CO)9(p.-

H)2(C6H2 R'R2) (where R' = H, R2 = F, Cl, CR3 ; R1 = CH3,R2 = CH3 ).

4.1.1 Attack on Metal Framework

The benzyne cluster, Os 3(CO)9(t-H)2(C6H4), is readily activated using

trimethyl N-amine oxide and acetonitrile to yield both the mono- and bis-substituted

acetonitrile derivatives."

I eq. Me 3NO 0s3(CO)8(MeCN)(H)2(C 6H4)

MeCN

Os3(CO)i)2(C6H4)

MeCN '

2 eq. Me3NO 0s3(CO)7(MeCN)2(H)2(C6H4)

Scheme 4.1.1.1: Reaction of 0s3(CO)9(H)2(C6H4) with 1 and 2 eqs. of amine oxide

Chapter Four

These clusters are both highly reactive and air sensitive, and they both react

readily with PPh 3 and P(OMe) 3 to yield the clusters 0s 3(p.-H) 2(CO)8(PR3)(C6H4) and

Os3(.t-H)2(CO)7(PR3)2(C6H4).

Both these clusters can also be synthesised by the photolysis of the face

capped benzene clusters Os3(CO)9(PR3)(t3-ri 2 :ii2 :ii 2 -C6116), where n = 1,2, and R

Ph, OMe.

hv/toluene Os3(CO)9..(PR3)(C6H6) 5°C ' Os3(CO)9..(PR3)(C61-I4)

Scheme 4.1.1.2: Reaction of face capping cluster Os3(CO)9(PR3)(j43-7, 2 :1 2 :11 2 -C6116) to yield the

benzyne cluster Os 3(4-H 2(CO) 9.(PR3)(C6H4)

In the mono-substituted product two possible isomers can occur, and they are

shown below in Figure 4.1.1.1.

Figure 4.1.1.1: Two possible isomers of 0s3(4-H)2(CO)8(PR3)(C6H4)

The isomers are either axial or equatorially substituted. In the case of PPh 3 ,

the major isomer is the axial substituted cluster, while for the P(OMe) 3 , the major

isomer is the equatorial substituted cluster. This is mainly due to the steric

requirements of the two types of phosphine ligand. The steric repulsion between the

Chapter Four

bulky PPh3 ligand and the C 6H.4 moiety is minimised by the PPh3 occupying the axial

position.

The bis-substituted cluster 0s 3 (j.i-H)2(CO)7(PPh3)2(C6H4) appears as only one

isomer, while the cluster Os 3(.t-H)2(CO)7 {P(OMe) 3 } 2(C6H4) appears as two isomers.

The 31P NM1R shows one signal for one of the hydrides coupling to both phosphines,

and one signal for the other hydride coupling to only one of the phosphines, indicating

the structure below for the Os 3 (t-H)2(CO)7(PPh3)2(C6H4) cluster.

Figure 4.1.1.2: Isomer for the cluster Os 3(4-H)2(CO)7 (PPh3)2(C6F4)

The cluster Os3(t-H)2(CO)7 {P(OMe)3 } 2(C6H4) exists as two isomers, and the

31P NMR indicates that the molecule is asymmetric. ( ' ) The NMR indicates that one of

the hydrides is trans to one phosphite and cis to the other, while the other hydride is

cis to only one of the phosphites.

The benzyne cluster has been shown to undergo reactions with

diphenylacetylene 2 to yield the disubstituted cluster 0s 3(CO)7(C 6H4){PhCC(H)Ph}2.

The benzyne cluster is activated by amine oxide and acetonitrile to yield the cluster

Os3(9-H)2(CO)7(C6}{4)(MeCN)2. This reactive cluster undergoes reaction at room

temperature to produce the disubstituted cluster.

97

Chapter Four

aim

fIi

040

CW Y a4 OM W

a311'lJp

cm

Figure 4.1.1.3: Molecular structure of Os 3(-H)2(CO)7 (C6H4)(PhCC(H)Ph) 2

The diphenylacetylene ligands have inserted into the two cluster hydrides, and

these are now bonded to one of the acetylene carbons. The ligands bridge an edge,

and each acts as a three electron donor, donating two electrons via a it bond, and one

electron through a a bond. Os(3) is it bound to C(29) and C(28), and Os(1) is a

bound to C(28). The cluster is a 48 electron species, with each metal atom obeying

the 18 electron rule.

The Os-Os distances are significantly shorter at 2.717(2)A for Os(2)-Os(3)

compared to 2.877(3)A in the parent cluster Os 3(CO)i2. 3 The acetylene bridge exerts

a shortening effect on the Os-Os bond distance.

4.1.2 Attack on the Arene Ring

The benzyne ligand in this cluster will undergo Friedel-Crafts acylation and

ailcylation under mild conditions, displaying the nucleophilicity of the arene ligand

despite the loss of electron density upon co-ordination to the metal cluster. (4)

98

Chapter Four

When an arene ring co-ordinates to a cluster, the electron density of the arene

will decrease and, the arene is therefore deactivated towards reaction with

electrophiles. For example, in the face capping benzene cluster Os 3(CO)9(C6H), the

co-ordinated benzene ligand easily undergoes reaction with nucleophiles, which is in

contrast to the behaviour of free benzene which favours reaction with electrophiIes."

In the benzyne cluster, although there is a loss of electron density on the arene

ligand, the cluster readily undergoes reactions under Friedel-Crafts conditions,

yielding acylated and alkylated products.

0s3(C0)9(H)2(C6H4) Rd/Aid 3

0s3(CO)9(H)2(C6H3R) 2' OoC to RI

where R= CH3 CO, or But

Figure 4.1.2.1: Acylation and alkylation of 0s 3(CO)9(H)2(C6H3R)

The products have the same JR pattern as the parent cluster, but the

absorptions shift 1-5 wavenumbers higher for acylation and 1-3 wavenumbers lower

for alkylation. This implies that electrophilic sustitution does not change the symmetry

of the molecule but does slightly change the electron density on the arene and the

cluster carbonyl ligands.

In the case of acylation, the presence of an electron withdrawing group

COCH3 decreases the electron density on the arene and the metal framework.

Therefore back donation from the metal atoms to the carbonyls is weakened, which in

turn results in stronger bonding between the C and the 0 atoms of the carbonyl. The

IR is therefore shifted to higher wavenumbers.

Chapter Four

In the case of alkylation the tertiary butyl group is weakly electron donating,

and the result is the opposite to above, weakening the bonding between the C and the

0 atoms of the carbonyl.

4.2 Reactions of Clusters Os 3(CO)9(9-H)2(C6H2R'R2) (where R' = H, R2 = F, Cl,

CH3; R' = CR3, R2 = CH3) Towards Acylation

A carbon disulphide solution of aluminium chloride and acetyl chloride was

cooled to 0 CC. A solution of 0s3(C0)9(j.i-H)2(C6H2R1 R2) in carbon disulfide was

added dropwise over 1 hour, and the resultant solution was allowed to warm to room

temperature. The solution turned pale brown upon warming to room temperature, and

the solvent was removed under vacuum. In each case one major product was

separated chromatographically using hexane/dichloromethane (1:1 v/v) as eluent. The

products were identified as 0s 3(CO)9(1.t-H) 2 {C6HR'R2(COCH3)} on the basis of IR,

and mass spectra, and in addition for 25, by 111 NMR.


In the Table 4.2.1, all the relevant spectroscopic data is shown. For the IR

spectra the peaks of the parent complexes are also shown.

100

Chapter Four

Os3(CO)94i-H)2 {C6H2F(COCH3)}, 25

IR (vCO)/ cm'

Acylated: 2116, 2085, 2058, 2038, 2024, 2010, 2002

Parent: 2114, 2083, 2056, 2035, 2021, 2007, 2000

MS/amu

M 960 (caic. 960)

Os3(CO)9(9-ll)2 C(,H2Cl(COCH3)), 26

ER (vCO)/ cm'

Acylated: 2112, 2085, 2059, 2039, 2028, 2014, 2006

Parent: 2110, 2083, 2058, 2037, 2025, 2011, 2003

MS/amu

M= 978 (caic. 976)

Os3(CO)9(-ll)2{C6H2(CB3)(COCH3)}, 27

ER (vCO)/ cm'

Acylated: 2113, 2082, 2054, 2035, 2025, 2006

Parent: 2109, 2079, 2052, 2033, 2022, 2002

'MS/amu

M+ 954 (calc. 956)

Os3(CO) 9(9-H)2 1(ortho-C6H(CH3)2(COCH3)}, 28

ER (vCO)/ cm

Acylated: 2110, 2082, 2054, 2036, 2024, 2008

Parent: 2107, 2079, 2053, 2033, 2022, 2006

MS/amu

M+ = 975 (calc. 970)

Os3(CO)9(-H)2 1(meta-C6H(CH3)2(COCH3)}, 29

JR (vCO)/ cm'

Acylated: 2108, 2078, 2054, 2033, 2023, 2008

Parent: 2105, 2076, 2052, 2032, 2021, 2005

MS/amu

M = 972 (caic. 970)

Table 4.2.1: Spectroscopic data for the acylated cluster species

101

Chapter Four

All of the products were identified on the basis of their mass specra, which

showed the parent ion peak followed by loss of carbonyls. The IR spectra in the

carbonyl stretching region are all shifted by 1-3 cm' higher energy when compared to

the parent clusters. As discussed previously this is because of the electron withrawing

nature of the -COCH 3 group, affecting the carbonyl ligands of the cluster.

IR were attempted on all of the products but there was no evidence for any

peaks in the region 1600cm' as expected for a -COCH 3 group. However the solutions

were very weak as a result of the very low yields of the reactions.

The 'H NIMIR spectrum of 25 was recorded in CD 202, and four resonances

were observed at ö values 7.84 (1H), 7.36 (1H), 2.64 (1H), and -18.3 (1H). These

resonances can readily be assigned to the protons on the fiuorobenzene ring and the

hydrides on the cluster.

Rb C—C(HC)3

Fla— ij—F

Hd

5 Hd

H 8/PPM

Ha 7.84 (d)

Hb 7.36(d)

Hc 2.64(s)

Hd -18.3

Figure 4.2.1: The 'H NMR data for 25

102

Chapter Four

The NMR data implies that the -COCH3 group occupies the position oriho to

the F atom of the ring. This is expected as -F is an ortho/para director. As the ortho

position is occupied exclusively, this indicates that the para position is sterically

hindered by the Os cluster, and the bonded carbonyl ligands.

Although no 'H NTvIR spectrum was possible for 26, the product is expected

to be the in the same configuration as 25, with the -COCH 3 group occupying the

position ortho to the -Cl on the chlorobenzene ring.

The parent toluene cluster 17 exists in a different predominant isomeric form,

with the methyl group in a position furthest away from the Os cluster. The ortho/para

directing nature of the methyl group gives two possible sites for the -COCH 3 group to

occupy, both of which are ortho to the methyl group.

,$ H3C—C CH3

OS-OS

Figure 4.2.2: The structure of 0s 3(CO)9(H)2{C6H2(CH3)(COCH3)}

As in the acylation reactions of the fluoro- and chlorobenzene clusters, one of

the two possible sites for the -COCH 3 group to occupy is hindered by the cluster. The

most likely position is that shown above with the -COCH 3 group in the ortho site

furthest away from the cluster.

To investigate further if the -COCH3 group could occupy the hindered site

nearest to the cluster, the acylation reaction was attempted on 18,

103

Chapter Four

0s3(CO)9(H)2(C6H2(CH3)2 . This complex has two vacant sites in the ortho-xylene

ring, both of which are hindered sites near to the cluster.

Figure 4.2.3: The structure of 0s 3(CO)9(H)2 {C6H(CH3)2(COCH3))

The reaction was successful, but in lower yields than the other acylated

clusters. This indicates that the site nearest to the cluster can be occupied, although

the low yield, 6%, implies that there is a steric interaction with the Os cluster.

In the acylation reaction of 19, the resultant cluster, 29, is expected to have

the -COCH3 group in a position between the two methyl groups of the meta-xylene

ring.

[-I

Figure 4.2.4: The structure of 0s 3(CO)9(H)2 {C6H(CH3)2(C0CH3)}

The reaction proceeds in yields similar to that for 25, 26, and 27, indicating

that the reaction produces the structure shown above with the -COCH 3 group in the

site furthest away from the cluster.

104

Chapter Four

Conclusion

In all the acylation reactions the IR spectra are shifted 1-3 cm' higher,

indicating the presence of a -COCH 3 group. The yields of the acylated complexes are

all very low and the 'H NMR data was only produced for one of the complexes. This

data indicated that the acyl group was occupying the position furthest away from the

cluster, indicating that the -COCH3 group is sterically hindered from occupying the

site nearest to the cluster. Although this position does not appear to be favoured, in

the acylation reaction of the ortho-xylene cluster the acylated cluster is formed. As the

methyl groups are occupying the sites furthest away from the cluster, the acyl group

must occupy a hindered site nearest to the cluster.

In general, it is assumed that the -COCH 3 group is hindered from occupying a

site nearest to the cluster, and that where possible it avoids occupying these sites.

4.3 Reaction of 0s3(CO)9(p.-H)2(C6H3F) with 2-butyne

A dichloromethane solution of 0s3(C0)9Qt-H)2(C6H3F) and excess 2-butyne

was activated by the dropwise addition of trimethylamine N-oxide and left to react

over 1 hour. The solvent was removed under vacuum and two main products were

separated chromatographically using hexane as eluant. In order of elution these

products were identified as Os3(CO)8(.t-H)(CH2CHCHCH3)(C6H3F) 30 and

0s3(CO)8(9-H)(CH3CCCH3)(C6H3F) 31, on the basis of their IR, and mass spectra,

and in addition for 31 'H NIvIR, and for 30 X-ray crystallography.

105

Chapter Four


Clusters 30 and 31 were characterised on the basis of their mass spectra which

showed the parent ion peaks at M= 945 (calc. 945), and M= 953 (calc. 945) amu

respectively, followed by the subsequent loss of carbonyls. The IR spectra of the two

species in the carbonyl region are quite similar, although cluster 31 has an extra peak

at 2057 cm". Both spectra indicate that only terminal carbonyls are present.

The 'H NMR spectra of both complexes were recorded, but in the case of 30

the sample was too weak to give a meaningful spectrum. The spectrum of 31 shows

seven resonances were observed at ö values 7.65 (1H), 6.96 (1H), 6.62 (t), 3.15 (3H),

3.00 (3H), -16.1 (1H), and -18.4(1H) ppm. Theses resonances can be readily assigned

to the hydrogens on the fiuorobenzene, and to the two -CH 3 groups of the 2-butyne.

H 8/PPM

Ha 7.65 (d)

Hb 6.96(m)

Hc 6.62 (t)

Hd 3.15 (s)

He 3.00(s)

Hf -16.1 (s)

Hg -18.4(s)

Figure 4.3.1: Cluster 31 and its 'H NMR data

106

Chapter Four

The observation of the two singlets at 3.00 and 3.15 ppm indicates that the

butyne remains intact and that the two -CH 3 groups are inequivalent. This suggests

the structure shown, with the butyne ligand replacing one of the carbonyls, and

bonding as shown. The butyne ligand acts as a two electron donor, and the cluster is

formally a 48 electron species. The signals due to the fluorobenzene ligand remains

the same as those for the parent cluster and suggests that it has not been altered. The

peaks at -16.1 and -18.4 ppm shows that there are two inequivalent hydrides in the

cluster.

This type of bonding mode with alkynes is well known in monomeric and

dimeric complexes, for example in Os(NO)(CO)(PR 3)2(PhCCPh) 6 and

Pd2C14(ButCCBut) (7)

X-ray Structure Determination Of 30

Single crystals of 0s 3(CO)g(p-H)(CH2CHCHCH3)(C6H3F) 30, suitable for X-

ray analysis were grown from a solution in pentane at 5 °C. The solid state molecular

structure is presented in Figure 4.3.2 together with some relevant bond lengths and

angles in Table 4.3.1. The structure confirms that the Os cluster framework remains

intact, and that the fluorobenzene ligand remains aryne bonded to the cluster. The 2-

butyne has undergone an H atom shift from one of the methyl groups to one of the

alkyne carbons, and has also added a further presumably cluster derived, H to the

second alkyne carbon. This generates an 3-1-methylallyl ligand which replaces one

carbonyl and one hydride ligand in the parent cluster. The remaining carbonyls are all

terminally bound, as indicated by the IR spectrum.

107

012

Os(1)-Os(2) 3.067(2) I Os(1)-C(7) 2.25(3)

Os(1)-Os(3) 2.816(2)

Os(2)-Os(3) 2.745(2)

Os(2)-C(1) 2.06(3)

Os(1)-C(6) 2.13(3)

Os(3)-C(1) 2.34(2)

Os(1)-C(8) 2.20(3)

Os(1)-C(9) 2.33(3)

C(7)-C(8)-C(9) 134(4)

C(10)-C(9)-C(8) 135(4)

C(9)-C(10) 1.34(4)

Chapter Four

032

Figure 4.3.2: Molecular structure of 0s3(CO)8(j.t-H)(CH2CHCHCH3)(C6H3F)

Os(3)-C(6) 2.23(3) I C(2)-F(2) 1.39(3)

C(1)-C(6) 1.42(3)

C(1)-C(2) 1.45(3)

C(2)-C(3) 1.32(4)

C(3)-C(4) 1.36(4)

C(4)-C(5) 1.45(4)

C(5)-C(6) 1.40(3)

mean C-0 1.167

Table 4.3.1: Selected bond lengths (A) and angles (°) for 0s3(CO)g(jt-H)(CH2CHCHCH3)(C6H3F)

108

Chapter Four

The cluster is a 48 electron species, with the butyne-derived ligand allyl

bonded to Os(1), and donating 3 electrons. A possible mechanism for the formation of

this ligand is represented in Figure 4.3.3.

Os

V \-H CH3

\ %—O

\I

s PClI

HI H H

Os V H CH3

Figure 4.3.3: Reaction of 2-butyne with the Os cluster to become an allyl group

The 1-methylallyl ligand is possibily formed in a one step process, with the

cluster hydride and the methyl proton undergoing transfer to their respective carbons,

causing the butyne to adopt an allyl bonding mode.

These 1-methyl allyl groups are generally formed using dienes or allyl halides,

not alkynes. Two well known examples are, the reaction of CoH(CO) 4 and

butadiene, (8) and the reaction of Pt(cod) 2 with an allyl halide. (9)

109

Chapter Pour

H H

CoH(C0)4 + C\ ,C, H2Cc?7CH_CI13

10

H H2 CH Co

H

Pt(cod)2 + H3C—C=C---C1 (cod)P(23

I I I Cl H H H

',

C + II/\

(cod)P\ /CH

CH

CH3

Figure 4.3.4: Formation of a 1 -methylallyl group from an alkyl halide and butadiene

In the butadiene reaction the hydride on the Co atom shifts to one of the

terminal -CH 2 groups, changing it into a -CH 3 group and causing the ligand to allyl

bond to the Co atom.

In the crystal structure of 30 the average Os-Os distance is 2.876 A, which is

almost the same as in the parent cluster 14 where the distance is 2.866 A. The butyne

Os-C bonds vary from 2.20(3) A to 2.33(3) A. The Os(1)-C(8) distance is the

shortest at 2.20(3) A, and Os(1)-C(9) is the longest at 2.33(3) A. The bond is

probably lengthened because of the close proximity of the C(1O)H 3 group to the

fluorobenzene ring. The steric interaction between the two is sufficient ot lengthen the

Os-C bond. The C(9)-C(10)H3 is very short at 1.34(4) A for a C-CH 3 bond, and is

almost approaching that of a C-C double bond.

110

Chapter Four

The bonds between the Os cluster and the fluorobenzene ring are slightly

distorted because of the butyne derived ligand. The ring has twisted slightly causing

the it-bond Os(3)-C(6) to shorten significantly to 2.23(3) A compared to 2.36(2) .A in

the parent cluster. This twisting has also shortened Os(2)-C(1) by 0.06 A to 2.06(3)

A. The other c- and it-bonds are almost the same length as in the parent cluster,

suggesting that the fiuorobenzene ring is closer, and more tightly bound than in the

parent cluster.

In the fiuorobenzene ring the C-C distances range from 1.32(4) A to 1.45(4)

A, and the C-F distance is 1.39(3) A. These compare almost exactly with those in the

parent cluster.

The carbonyls are all terminal, and have an average C-O length of 1.167 A.

This is very long compared to the parent clusters average of 1.14 A, and the longest

are those bonded to Os(1) which are 1.18(3) A and 1.20(3) A. This is due to the

presence of the butyne group, and the steric bulk of the group causes the carbonyls to

lengthen.

Conclusion

A second proposal for the mechanism for the conversion of the 2-butyne

ligand to a 1 -methylallyl ligand, which takes into account the characteristaion of both

30 and 31, and previous work on clusters, is shown in Figure 4.3.5.

111

Chapter Four

CH

CH3

H3C H 'C,

zi

Os Os

H—C—H

A

/ Os\

H,CH3

\çOscçCH

Figure 4.3.5: Stepwise formation of 1-methylallyl from 2-butyne

The proposed mechanism involves three main steps to change the ligand from

a 2-butyne to a I -methylallyl. The first step is the 2-butyne ligand bonding to an Os

atom in the cluster as a two electron donor, as in 31. A cluster hydride then transfers

to one of the alkyne carbons, breaking the triple bond. The ligand becomes it-bonded

to the Os atom, and a-bonds to an adjacent Os atom forming an edge bridging

alkylidene. This type of bonding mode is well known for alkynes, and is observed in

the Os cluster 0s3(CO)7(C6FL4)(PhCC(H)Ph)2 for the diphenylacetylene ligands, where

they have inserted into the bridging hydrides of the cluster. (2)

In this case the butyne then undergoes an internal hydrogen shift from the

terminal methyl group, breaking the bridging a-bond, and creating a 1-methylallyl

group. In the cluster 0s 3(CO)7(C6H4)(PhCC(H)Ph)2 there are no available hydrogens

to undergo a similar shift to create an allyl ligand.

The proposed mechanisms both seem possible explanations for the unexpected

formation of the 1-methylallyl ligand from 2-butyne, and the mechanism that

predominates depends upon species 31. This species is either the first step in the

112

Chapter Four

formation of the 1-methylallyl ligand, as in the second mechanism, or a separate

species, with the 2-butyne forming a 1-methylallyl ligand independently in one step.

113

Chapter Four

References

H. Chen, B.F.G. Johnson, J. Lewis, P.R. Raithby, I Organomet. Chem., 1991, 406, 219

H. Chen, B.F.G. Johnson, J. Lewis, P.R. Raithby, I. Organomet. Chem., 1989, 376, C7

M.R. Churchill, B.G. DeBoer, Inorg. Chem., 1977, 16, 878

H. Chen, B.F.G. Johnson, J. Lewis, Organometallics, 1989, 8, 2965.

M.A. Gallup, B.F.G. Johnson, J. Lewis, A.H. Wright, I. Chem. Soc., Dalton Trans., 1989, 481

J.A. Segal, B.F.G. Johnson, I Chem. Soc., Dalton Trans., 1975, 1990

T. Hosokawa, I. Moritani, S. Nishioka, Tetrahedron Lett., 1969, 3833

J.A. Bertrand, H.B. Jonassen, D.W. Moore, Jnorg. Chem., 1963, 2, 601

N.M. Boag, M. Green, J.L. Spencer, F.G.A. Stone, I Organomel. Chem., 1977, 127, C51

114

Chapter Five

Chapter Five

5 Experimental

5.1 General Experimental Procedures and Instrumentation

General

Trimethylamine-N-oxide dihydrate (Me 3NO.2H20), purchased from Aldrich,

was carefully dried by refluxing the sample (15g) in benzene (250 ml), typically

overnight, to remove the water of crystallisation via a Dean and Stark distillation. The

benzene was then decanted and the sample dried under vacuum on a Schienk line, and

sublimed prior to use. Addition of Me3NO to the reaction solutions was carried out

under an atmosphere of dry nitrogen, although no strict measurements were taken to

completely exclude air from the reaction systems.

Dichioromethane and diethyl ether were dried using CaH 2 and freshly distilled

prior to use. Acetonitrile was dried over 4A molecular sieves purchased from

Lancaster Chemicals. All other reagents were used as supplied without purification.

Osmium carbonyl was purchased from Oxkem Ltd. and all other reagents were

purchased from Aldrich or Lancaster Chemicals.

Seperations

All separations were achieved chromatographically on silica, on the open

bench without any precautions to exclude air. Thin layer chromatography (tic) was

carried out using glass plates (20 cm x 20 cm) coated with a 0.25 cm layer of silica

115

Chapter Five

gel 60 F254, which were supplied by Merck. Column chromatography was carried out

using a 50 cm long glass column with an internal diameter of 3 cm, fitted with a 100

ml solvent reservoir, and a facility for pressurisation. The column was packed with 60

mesh silica and the eluants used for both column and thin layer chromatography were

mixed from standard grade laboratory solvents.

Crysiallisations

Single crystals of high quality were required for the collection of X-ray

diffraction data and were typically grown from pentane solutions at low temperature,

unless otherwise stated.

Infra-red Spectroscopy

Infra-red spectra were recorded in dichloromethane in NaCl cells (0.5 mm

path length) supplied by Specac Ltd., using a Perkin-Elmer Series 1600 fourier

transform instrument.

Mass Spectrometry

Fast atom bombardment mass spectra were obtained on a Kratos MS50TC

spectrometer which was run in positive mode. Samples were run in a matrix of 3-

NOBA (meta-nitrobenzyl alcohol).

116

Chapter Five

AMR Spectroscopy

'H NIvIIR spectra were recorded on Bruker WH 200 or 250 MHz fourier

transform instruments. All spectra described herein were recorded in deuterated

solvents and were referenced to an internal trimethylsilane (TMS) standard.

Single Crystal X-ray Diffraction Studies

Diffraction data were collected on a Stoe Stadi 4-circle diffiactometer. An

Oxford Cryosystems device was used for low temprature data collection.' The

appropriate crystal data, data collection and structural refinement parameters are

presented in the text, and full crystallographic listings are given in the appendices. All

refinements were carried out using the crystallographic program SHELXL 93, (2) and

all figures were produced using SHELXTL PC. 3 When metal hydrides could not be

located by direct experiment they were positioned using the program XHYDEX. 4

This program employs a potential energy technique in order to define the most likely

site for a hydride ligand to adopt in a cluster. Optimum positions are found for each

postulated hydride site by minimisation of the potential energy of the intramolecular

non-bonded interactions involving the hydride. The resultant potential energy enables

a quantitative comparison to be made of the various possible hydride locations on the

cluster.

117

Chapter Five

5.2 Experimental Details for Chapter Two

Preparation of ('t7neda,)Pd'Cl,.)2 (5)

Palladium chloride (0.9895g, 5.55mmol) was dissolved in acetonitrile (50 ml)

and was heated at reflux for lh. The solution was allowed to cool to room

temperature and a pale yellow suspension formed. A slight excess of tmeda (1.20 ml,

1.5 mol. equiv.) was added, and the suspension immediately turned bright yellow in

colour. The precipitate was filtered off, and washed three times with diethyl ether (3 x

15 ml). The resultant yellow solid was dried under vacuum. (Yield 84%)

Preparation of (t,neda)Pd(Me)2 (5)

The compound (tmeda)Pd(Cl) 2 (1 .3624g, 4.63 mmol)) was suspended in diethyl

ether (30 ml) and cooled to -30 °C using an acetone/CO2 bath. A slight excess of

MeLi (7.5 ml, 2.5 mol. equiv.) was added with stirring. The solution was allowed to

warm to 0 °C and was stirred for a further lh. Ice cold water (10 ml) was added until

a clear organic layer and a black water layer had formed. The organic layer was

seperated and dried over MgSO 4, before the solvent was removed under reduced

pressure leaving a white precipitate. (Yield 77%)

Preparation of (tmeda)Pd(Me) (7) (5)

The compound (tmeda)Pd(Me)2 (0.3565g, 1 .4Ommol)) was dissolved in

benzene (10 ml) before the addition of Mel (0.12 ml, 1.1 mol. equiv.). A brown

precipitate was formed, which was filtered and dried at reduced pressure. (Yield 91%)

118

Chapter Five

Preparation of (rmeda)Pd(COMe) (6)

The compound (tmeda)Pd(Me)(I) (0.5549g, 1 .52mmol)) was dissolved in

chloroform (5 ml) and a slow stream of CO gas was bubbled through the solution for

the period of im. The solution immediately turned pale brown and was left to stir for

I under a CO atmosphere. The solution was then reduced in volume to 1 cm' under

vacuum, and pentane (10 ml) was added. A light brown precipitate appeared which

was filtered off and dried at reduced pressure. (Yield 64%)

Preparation of (bpy)Pd(COMe) (I) (7)

The compound (tmeda)Pd(COMe)(I) (0.55g, 1 .4Ommol) was dissolved in

dichloromethane (50 ml) and the solution was cooled to 0 T. An excess of 2-2'

dipyridyl (bpy) (0.7168g, 3 mol. equiv.) was added and the solution was stirred at 0

°C for 18h. The solvent was removed at reduced pressure and the resultant orange

solid was washed with diethyl ether (2 x 20 ml). The compound was finally dried at

reduced pressure. (Yield 96%)

Synthesis of {(bpy)Pd(Cd -Ii 000Me)} (OTj)

The compound (bpy)Pd(COMe)(I) (46mg, 0.1 lmmol) was dissolved in

dichloromethane (40 ml) and the solution was cooled to 0 T. To the solution was

added acetonitrile (2 ml), cyclohexene (0.016 ml, 1.5 mol. equiv.) and silver triflate

(41mg). A white solid immediately separated and the solution was allowed to stir at 0

°C for a further 3h. The solution was filtered and the solvent was removed under

reduced pressure. The resultant residue was washed with diethyl ether (2 x 40 ml) to

remove any residual acetonitnle and dried under vacuum. (Yield 12%)

119

Chapter Five

Spectroscopic data for {(bpy)Pd(C 6H1000Me)}(OTf): IR v(COCH3) 1690(m); MS: M4 = 387(calc.

387) amu

Synthesis of {(bpy)Pd(C 6H8COMe)} (OTJ)- (1,3)

The compound (bpy)Pd(COMe)(I) (45mg, O.lOmmol) was dissolved in


added acetonitrile (1.5 ml), 1,3 cyclohexadiene (0.015 ml, 1.5 mol. equiv.) and silver

trifiate (41mg). A white solid immediately separated and the solution was allowed to

stir at 0 °C for a further 3h. The solution was filtered and the solvent was removed

under reduced pressure. The resultant residue was washed with diethyl ether (2 x 40

ml) to remove any residual acetonitrile and dried under vacuum. (Yield 10%)

Spectroscopic data for {(bpy)Pd(C 6H3COMe))(OTf): IR v(COCH3) 1682 (m); MS: M = 385 (caic.

385) amu

Synthesis of {(bpy)Pd(C61LCOMe)} (OTj)- (1,4)

The compound (bpy)Pd(COMe)(I) (100mg, 0.23mmol) was dissolved in


added acetonitrile (1.5 ml), 1,4 cyclohexadiene (0.028 ml, 1.5 mol. equiv.) and silver

trifiate (96mg). A white solid immediately separated and the solution was allowed to




Spectroscopic data for {(bpy)Pd(C 6H8COMe)}(OTf): IR v(COCH 3) 1656 (m); MS: M = 385 (caic.

385) amu

120

Chapter Five

Synthesis of {(bpy)Pd(C 8H12COMe)} (OTj)

The compound (bpy)Pd(COMe)(I) (43mg, 0. lOmmol) was dissolved in


added acetonitrile (1.5 ml), cyclooctadiene (0.020 ml, 1.5 mol. equiv.) and silver

triflate (41mg). A white solid immediately separated and the solution was allowed to




Spectroscopic data for {(bpy)Pd(C 8H12COMe)}(OTf): IR v(COCH3) 1654 (m); MS: M = 413 (caic.

413) amu

Attempted Synthesis of {(bpy)Pd(C6 -I6COMe)} (0 Tj)



added acetonitrile (2 ml), benzene (0.020 ml, 1.5 mol. equiv.) and silver triflate

(5 0mg). A white solid immediately separated and the solution was allowed to stir at 0



remove any residual acetonitrile and dried under vacuum.

Attempted Synthesis of ((bpy)Pd(C 6Hs(F)COMe)} (07'))


dichioromethane (40 ml) and the solution was cooled to 0 °C. To the solution was

added acetonitrile (1.5 ml), fluorobenzene (0.017 ml, 1.5 mol, equiv.) and silver

triflate (4 1mg). A white solid immediately separated and the solution was allowed to

121

Chapter Five



ml) to remove any residual acetonitrile and dried under vacuum.

Attempted Synthesis of ((bpy)Pd(C 6J-15(Br)COMe)} (OTJ)

The compound (bpy)Pd(COMe)(I) (45mg, O.lOmmol) was dissolved in

dichloromethane (40 ml) and the solution was cooled to 0 °C. To the solution was

added' acetonitrile (1.5 ml), bromobenzene (0.017 ml, 1.5 mol. equiv.) and silver

triflate (41mg). A white solid immediately separated and the solution was allowed to




Attempted Synthesis of {(bpy)Pd(C 8H8COMe)} (OTJ)

The compound (bpy)Pd(COMe)(I) (46mg, 0.1 Immol) was dissolved in

dichioromethane (40 ml) and the solution was cooled to 0 T. To the solution was

added acetonitrile (1.5 ml), cyclooctatetraene (0.018 ml, 1.5 mol. equiv.) and silver

triflate (42mg). .A white solid immediately separated and the solution was allowed to




122

Chapter Five

Attempted Synthesis of {(bpy)Pd(C6H5(Me)COMe)} (OTj)

The compound (bpy)Pd(COMe)(I) (48mg, 0.1 immol) was dissolved in


added acetonitrile (1.5 ml), toluene (0.018 ml, 1.5 mol. equiv.) and silver trifiate





Attempted Synthesis of {(bpy)Pd(C6 -14(OH)2COMe)} (OTj)


dichloromethane (40 ml) and the solution was cooled to 0 °C. To the solution was

added acetonitrile (1.5 ml), hydroquinone (17mg, 1.5 mol. equiv.) and silver trifiate





Attempted Synthesis of (tmeda)Pd(Ph) 2

The compound (tmeda)PdC12 (120mg, 0.41mmol) was suspended in diethyl

ether (30 ml) and cooled to -30T using an acetone/CO2 bath. A slight excess of PhLi

(0.5 ml, 1.5 mol. equiv.) was added with stirring. The solution was allowed to warm

to 0°C and was stirred for a further lh. Ice cold water (10 ml) was added until a clear

organic layer was separated and dried over MgSO 4 . The solvent was removed under

reduced pressure.

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Chapter Five

Spectroscopic data: 'H NIvIR (CDCI 3): 6 2.54 (s, 2 x -N(CH3)2), 2.26 (s, 2 x -CH2-)

5.3 Experimental Details for Chapter Three

Preparation of 0s3(CO) jo(NCMe) 2

0s3(CO) 1 2 (0.5021g, 0.55mmol) was dissolved in a solution of

dichloromethane (200 ml) and acetonitrile (50 ml). A solution of Me 3NO (0.1052g.

2.5 mol. equiv.) in acetonitrile (100 ml) was added dropwise over 3h and the resultant

solution was allowed to stir for a further lh. The solution was then filtered through

silica to remove any unreacted starting material and the solvent was then removed

under reduced pressure.

Synthesis of 0s 3(CO) 9(H)2(C6H3F)

The compound 0s 3(C0) 1o(NCMe) 2 (0.5243g, 0.56mmol) was dissolved in

flourobenzene (50 ml) and was heated at reflux for lh. The solution was allowed to

cool to room temperature before being filtered through silica. The solvent was

removed under reduced pressure followed by product seperation by tic using hexane

as eluant. One major band was produced as well as two minor bands and cluster

decomposition. These were extracted into dichloromethane and characterised

spectroscopically as 0s 3(CO) 1 2 12 (yellow), 0s3(C0) 10(NCMe)2 13 (yellow), and

0s3(CO)9(H')2(C6H3F) 14 (yellow, 20 %). Single crystals of 14 suitable for X-ray

diffraction analysis were grown.

124

Chapter Five

Spectroscopic data for 0s 3(CO)9(H')2(C6H3F): IR (CH 202): v(CO) 2114 (m), 2083 (s), 2056 (s), 2035

(m), 2021 (m), 2007 (m), 2000 (sh) cm -'; 'H NMR (CDC1 3): 8 7.65 (d, J= 7.82 Hz, 1H), 6.95 (m, J

5.82 Hz, 1H), 6.58 (t, J= 7.74 Hz, 1H), -18.3 (s, 2H) ppm; MS: M= 920 (caic. 918) amu

Crystal measurement and details for 0s 3(CO) 9(H)2(C6H3F): Formula C 15H5F090s3, M.Wt. 918.79

amu, crystal size/mm 0.36 x 0.32 x 0.24, crystal system Monoclinic, space group P2(1)/c, a=

9.4776(8) A, b= 10.429(2) A, c= 20.023(2) A, oL= 90 0 3= 98.578(8) o . 90 0 Volume= 1957.0(4)

A, Z= 4, F(000) 1616, Pcaic= 3.118 Mgm 3 , ? (Mo-K,,,)= 0.71073 A, temperature 293(2) K, 20

range= 2.06 to 30.00 0 measured reflections 7334, unique observed reflections [1>2a(I)1 5713, No.

of refined parameters 259, goodness of fit on F 1.015, final R indices R [I>2c(I)J R1 0.0546,

wR2= 0. 1092, R indices (all data) R1= 0. 1073, wR2= 0.1333

Synthesis of 0s 3(CO) 9(H)2(CJI3C1)

The compound 0s3(CO) io(NCMe)2 (0.8205g. 0.88mmol) was dissolved in

chlorobenzene (50 ml) and was heated at reflux for lh. The solution was allowed to



as eluant. One major band was produced as well as two minor, bands and cluster

decomposition. These were extracted into dichioromethane and characterised

spectroscopically as 0s 3(CO) 12 12 (yellow), 0s3(CO) io(NCMe)2 13 (yellow), and

0s3(CO)9(H)2(C6H3C1) 15 (yellow, 22%). Single crystals of 15 suitable for X-ray


Spectroscopic data for 0s 3(CO)9(H)2(C6H3C1): JR (CH 202): v(CO) 2110 (m), 2083 (s), 2058 (s),

2037 (m), 2025 (m), 2011(m), 2003(sh), 1987 (m) cm'; 'H NMR (CDC1 3): 8 7.89 (d, J= 8.4 Hz,

1H), 7.83 (d, J= 7.8 Hz, 1H), 7.30 (d, J= 7.3 Hz, IH), 6.82 (t, J= 7.5 Hz, 11-I'), -18.7 (s, 2H); MS: M=

936 (calc. 934) ainu

Crystal measurement and details for 0s 3(CO)9(H)2(C6H3C1): Formula C 15H50090s3 , M.Wt. 935.24

amu, crystal size/nun 0.39 x 0.27 x 0.21, crystal system Triclinic, space group P-i, a= 8.666(5) A,

b= 9.309(5) A, c= 14.107(8) A, a= 100.04(3) 0 P= 97.27(2) 0 116.83(3) 0 Volume 972.3(9)

125

Chapter Five

A, Z= 2, F(000)= 824, p = 3.194 Mgm 3 , ? (Mo-K,)= 0.71073 A, temperature 150(2) K, 20

range= 2.54 to 25.06 0 measured reflections 3469, unique observed reflections [I>2c(I)] 3444, No.

of refined parameters 255, goodness of fit on F 1.027, conventional R [F>4c(F)] Ri- 0.0502, wR2=

0.0883, R indices (all data) R1=0.0242, wR2= 0.0860.

Attempted Synthesis of 0s3(CO)9(H)2(Cdl3Br)

The compound 0s3(CO) io(NCMe)2 (0.5673g, 0.61mmol) was dissolved in

bromobenzene (50 ml) and was heated at reflux for lh. The solution was allowed to





spectroscopically as 0s3(CO) 12 12 (yellow), 0s3(CO) 10(NCMe)2 13 (yellow), and

0s3(C0) 1o(jt-Br)2 16 (orange, 15%). Single crystals of 16 suitable for X-ray


Spectroscopic data for 0s 3(C0)9(H)2(C6H3Br): IR (CH202): 2113 (m), 2082 (s), 2053 (s), 2014 (w),

2007 (s), 1998 (sh) cm; 1H NUR (CDC1 3): signal oscured by unreacted bromobenzene; MS: M=

1012 (calc. 984) amu

Synthesis of Os 3(CO)9(H)2(C5J-L31vIe)

The compound 0s3(CO) jo(NCMe)2 (0.5998g. 0.64mmol) was dissolved in

toluene (50 ml) and was heated at refiux for lh. The solution was allowed to cool to

room temperature before being filtered through silica. The solvent was removed under

reduced pressure followed by product seperation by tic using hexane as eluant. One

major band was produced as well as two minor bands and cluster decomposition.

These were extracted into dichloromethane and characterised spectroscopically as

126

Chapter Five

0s3(CO)12 12 (yellow), 0s3(CO)io(NCMe)2 13 (yellow), and 0s3(CO)9(H)2(C6H3Me)

17 (yellow,24%). Single crystals of 17 suitable for X-ray diffraction analysis were

grown.

Spectroscopic data for 0s 3(CO) 9(H) 2(C6H3Me): IR (CH2C1 2): 2109 (m), 2079 (s), 2052 (s), 2033 (s),

2022 (w), 2002 (s), 1997 (sh) cm'; 'H NMR (CDC1 3): 8 7.84 (d, J= 8.3 Hz, 111), 7.74 (d, J= 8.3 Hz,

111), 7.71 (s, 111), 6.73 (m, 1H), 6.73 (dd, J= 8.3 Hz, 1H), 2.45 (s, 3H), 2.31 (s, 314), -18.5 (s, 2H);

MS: M 4 = 918 (calc. 914) amu

Crystal measurement and details for 0s 3 (CO)9(H)2(C6H3Me): Formula C, 6H8O9Os3 , M.Wt. 914.82

amu, crystal size/nun 0.43 x 0.23 x 0.19, crystal system Triclinic, space group P-i, a= 9.260(2) A,

b= 13.115(2) A, c= 16.633(3) A, a= 91.01(2) 0, 3= 93 . 58(2) 0, y= 92 . 23(2) 0 , Volume 2014.1(6)

A, Z= 4, F(000) 1616, Pcalc= 3.017 Mgm 3 , ?. (Mo-K)= 0.71073 A, temperature 150(2) K, 20

range= 2.59 to 27.53 0 measured reflections 9479, unique observed reflections [1>2(I)] 9234, No.

of refined parameters 505, goodness of fit on F 1.008, final refinement factor indices (R) [I>2c(I)]

R1= 0.0503, wR2= 0. 1215, R indices (all data) R1= 0.0786, wR2= 0.1358.

Synthesis of 0s 3(C0) 9(H) 2 {0rth0-C6 12(Me)2}

The compound 0s3(CO) jo(NCMe)2 (0.5746g, 0.62mmol) was dissolved in

ortho-xylene (50 ml) and was heated at reflux for lh. The solution was allowed to





spectroscopically as 0s3(CO)12 12 (yellow), 0s 3(CO) jo(NCMe)2 13 (yellow), and

0s3(CO)9(H)2 [ortho-C6H2(Me)2] 18 (yellow, 23%). Single crystals of 18 suitable for

X-ray diffraction analysis were grown.

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Chapter Five

Spectroscopic data for 0s3(CO)9(H) 2 {ortho-C 6H2(Me)2}: IR (CH202) v(CO) 2107 (m), 2079 (s),

2053 (s), 2033 (s), 2022 (m), 2006 (s), 1997 (m), 1981 (m) cm'; 'H NTvIR (CDC1 3): S 7.60 (s, 2H),

2.19 (s, 611), -18.1 (s, 2H); MS: M= 930 (caic. 928) amu

Crystal measurement and details for 0s 3(CO)9(H)2(C6H3(Me)2): Formula C 17H, 0090s3

M.Wt. 928.85 arnu, crystal size/mm 0.23 x 0.16 x 0.06, crystal system Triclinic, space group P-i, a=

8.873(11) A, b= 9.708(8) A, c= 13.664(12) A, cx= 79.95(7) 0 = 73.56(8) 0 y= 64.88(8) 0

Volume= 1019(2) A, Z= 2, F(000) 824, Pcalc= 3.028 Mgm 3 , ? (MOKa)= 0.71073 A, temperature

150(2) K, 20 range= 2.61 to 22.48 0 measured reflections 2341, unique observed reflections

[1>2(I)] 2333, No. of refined parameters 179, goodness of fit on P 1.016, conventional R [F>4c(F)]

R1= 0.045 1, R indices (all data) R1= 0.0660, wR2= 0.1143.

Synthesis of 0s 3(CO)p(H)2(meta-Cd-12(Me)2)

The compound 0s3 (C0),o(NCMe)2 (0.5243g, 0.56mmol) was dissolved in

meta-xylene (50 ml) and was heated at reflux for lh. The solution was allowed to




decomposition. These were extracted into dichioromethane and characterised

spectroscopically as 0s 3(CO) 12 12 (yellow), Os3(C0) 1o(NCMe)2 13 (yellow), and

0s3(C0)9(H)2[meta-C6H2(Me)2] 19 (yellow, 21%). Single crystals of 19 suitable for

X-ray diffraction analysis were grown.

Spectroscopic data for 0s3(C0)9(H)2{meta-C 6H2(Me)2 }: JR (CH202) v(CO) 2105 (m), 2076 (s),

2052 (s), 2032 (s), 2021 (m), 2005 (m), 1997 (sh) cm'; 'H NMR (CDC1 3): 8 7.43 (s, 1H), 6.80 (s,

IH), 2.19 (s, 311), 2.17 (s, 3H), -18.X (s, 2H); MS: M= 932 (calc. 928) amu

Crystal measurement and details for 0s 3(C0)9(H)2(C6H3(Me)2): Formula C171-11009Os3

M.Wt. 928.85 arnu, crystal size/nun 0.25 x 0.16 x 0. 16, crystal system Triclinic, space group P-i, a=

8.257(3) A, b 9.114(4) A, c= 14.771(6) A, a= 90.70(3) 0 P= 100.92(4) 0 y= 109.80(3) 0

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Chapter Five

Volume= 1023.4(7) A, Z= 2, F(000) 824, Pcaic 3.014 Mgm 3 , X (Mo-K)= 0.71073 A,

temperature 150(2) K, 20 range= 2.67 to 30.07 0 measured reflections 6781, unique observed

reflections [I>2c(I)] 5984, No. of refined parameters 265, goodness of fit on P 0.999, conventional

R [F>4cy(F)] R1= 0.0442, R indices (all data) R1 0.0660, wR2= 0.1097.

Attempted synthesis of 0s 3(CO) 9(H)2 {para-C6H2(Me) 2}

The compound 0s3(CO) io(NCMe)2 (0.5548g, 0.59mmol) was dissolved in

para-xyiene (50 ml) and was heated at refiux for lh. The solution was allowed to cool

to room temperature before being filtered through silica. The solvent was removed

under reduced pressure followed by product seperation by tic using hexane as eluent.

Two major bands and cluster decomposition. These were extracted into

dichloromethane and characterised spectroscopically as 0s 3(CO) jo(NCMe)2 13

(yellow), and 0s 3(CO) 1 2 12 (yellow).

Reaction of 0s 3(CO) j o(NCMe) 2 and a-methylstyrene

The compound 0s 3(CO) jo(NCMe)2 (0.5126g, 0.55mmol) and cc-methylstyrene

(2-3 cm3 excess) were dissolved in octane (50 ml) and the mixture was heated at

reflux for 3h. The solution was allowed to cool to room temperature before being

filtered through silica. The solvent was removed under reduced pressure followed by

product seperation by tic using hexane as eluant. Four major bands were produced,

and these were extracted into dichloromethane and characterised spectroscopically as

0s3(CO)12 1 (yellow), 0s 3(CO) 1o(NCMe)2 2 (yellow), 0s3(CO)9(H)2

(C6H3(C(CH3)CH2)} 21 (yellow, 6%), and 0s3(CO)9(H)2 {C6H3(C(CH3)CH2)} 22

(yellow, 5%),

129

Chapter Five

Spectroscopic data for 21: JR v(CO) 2122 (w), 2100 (w), 2080 (s), 2064 (m), 2054 (s), 2037 (m),

2020 (m), 2008 (sh), 1999 (w) cm; MS: M= 941 (calc. 939) amu

Spectroscopic data for 22: JR v(CO) 2122 (w), 2077 (sh), 2065 (s), 2050 (m), 2039 (m), 2023 (m),

2016 (m), 2006 (sh); MS: M= 941 (calc. 939) amu

Reaction of 0s 3(CO) j o(NCMe) 2 and styrene

The compound 0s3(CO) 1o(NCMe)2 (0.5109g. 0.55mmoi) and styrene (2-3

cm excess) were dissolved in octane (50 ml) and was heated at refiux for 3h. The

solution was allowed to cool to room temperature before being filtered through silica.

The solvent was removed under reduced pressure followed by product seperation by

tic using hexane as eluant. Three major bands were produced, and these were

extracted into dichloromethane and characterised spectroscopically as 0s 3(CO) 1 2 12

(yellow), 0s3(CO)io(NCMe)2 13 (yellow), and 0s3(CO)9(H)2 {C6H3(CHCH2)} 23

(yellow, 10%).

Spectroscopic data for 0s3 (CO)9(H)2 {C6H3(CHCH2)): JR (CH202): v(CO) 2120 (w), 2079 (s), 2064

(s), 2054 (in), 2037 (m), 2021 (m), 2007 (m) cm -1 ; 1 H NMR (CDC1 3): sample to weak to asssign

MS: M 4 = 926 (calc. 926) amu

Reaction of 0s 3(CO) 1o(NCMe) 2 and 1,3 diisopropenylbenzene

The compound 0s3(CO) io(NCMe)2 (0.4982g, 0.53mmol) and 1,3

diisopropenylben.zene (2-3 cm 3 excess) were dissolved in octane (50 ml) and was

heated at reflux for 3h. The solution was allowed to cool to room temperature before

being filtered through silica. The solvent was removed under reduced pressure

followed by product seperation by tic using hexane as eluant. Two major bands were

130

Chapter Five

produced, and, these were extracted into dichioromethane and characterised

spectroscopically as 0s 3(CO) 12 12 (yellow) and 0s 3(CO) 10(NCMe)2 13 (yellow).

5.4 Experimental Details for Chapter Four

Synthesis of 0s 3(C0) 9(I-I)2 (C6H2(F) (COMe))

Aluminium trichloride (90mg, 0.67mmol) and acetyl chloride (3.3 ml) were

dissolved in carbon disulfide (20 ml) and the solution was cooled to 0 T. A solution

Of 0s3(CO)9(H)2(C6H3F) (45mg, 0.05mmol) in carbon disulfide (15 ml) was added

dropwise over lh. The resultant solution was allowed to warm to room temperature

over a further lh, before being filtered through silica. The solvent was removed under

reduced pressure followed by product seperation by tic using hexane-dichioromethane

(1:1 v/v) as eluant. One major band was produced as well as some cluster

decomposition. The major band was extracted into dichloromethane and characterised

spectroscopically as 0s 3(CO)9(H)2 { C6H2(F)(COMe) } 25 (yellow, 10%).

Spectroscopic data for 0s 3(CO)9(H)2 {C6H2(F)(COMe)}: JR v(CO) 2116 (m), 2085 (s), 2058 (s), 2038

(s), 2024 (m), 2010 (m), 2002 (w) cm'; MS: M"= 960 (960) ainu

Synthesis of 0s 3(CO)p(H) 2 (C6F12(Cl)(COMe))

Aluminium trichloride (110mg, 0.82mmol) and acetyl chloride (4.0ml) were


Of 0s3(CO)9(H)2(C6H3C1) (55mg, 0.06mmol) in carbon disulfide (15 ml) was added

131

Chapter Five


over a further lh, before being filtered through silica. The solvent was removed under

reduced pressure followed by product seperation by tic using hexane-dichioromethane



spectroscopically as 0s3(CO)9(H)2 { C6H2(Cl)(COMe) } 26 (yellow, 7%)

Specroscopic data for 0s 3(CO)9(H)2 {C6H3(C1)(COMe)}: IR v(CO) 2112 (m), 2085(s), 2059 (s), 2039

(m), 2028 (s), 2014 (m), 2006 (m) cm'; MS: M= 978 (caic. 976)

Synthesis of 0s 3(CO)p(H) 2 (C6112(Me) (COMe)]

Aluminium trichloride (134mg, 1.01mmol) and acetyl chloride (4.7 ml) were


of 0s3(CO)9(H)2(C6H3Me) (67mg, 0.07mmol) in carbon disulfide (20 ml) was added


over a further 1 h, before being filtered through silica. The solvent was removed under

reduced pressure followed by product seperation by tic using hexane-dichloromethane



spectroscopically as 0s3(CO)9(H)2 { C6H2(Me)(COMe) } 27 (yellow, 10%).

Spectroscopic data for 0s 3(CO)9(H)2 (C6H3(Me)(COMe)}: IR v(CO) 2113 (m), 2082 (s), 2054 (s),

2035 (m), 2025 (m), 2006 (m) cm'; MS: M += 954 (caic. 956)

Synthesis of 0s3(CO)9(H)2{Cd -I(Me)2(COMe)}

Aluminium trichloride (178mg, 1 .33mmol) and acetyl chloride (6.2th1) were


132

Chapter Five

Of 0s3 (C0)9(H)2 [oriho-C 6H2(Me)21 (89mg, 0.09mmol) in carbon disulfide (20 ml)

was added dropwise over lh. The resultant solution was allowed to warm to room

temperature over a further lh, before being filtered through silica. The solvent was

removed under reduced pressure followed by product seperation by tic using hexane-

dichloromethane (1:1 v/v) as eluant. One major band was produced as well as some

cluster decomposition. The major band was extracted into dichloromethane and

characterised spectroscopically as 0s 3(CO)9(H)2 (C6H(Me)2(COMe)) 28 (yellow,

6%).

Spectroscopic data for 0s 3(C0)9(H)2 { C6H(Me)2(COMe) }: JR v(CO) 2110 (m), 2082 (s), 2054 (s),

2036 (s), 2024 (m), 2008 (m) cm'; MS: M += 975 (calc. 970) amu

Synthesis of 0s 3(C0)p(H)2(C6H(Me) 2(C0Me)}

Aluminium trichioride (122mg, 0.91mmøl) and acetyl chloride (4.5 ml) were

dissolved in carbon disulfide (20 ml) and the solution was cooled to 0 °C. A solution

Of 0s3(CO)9(H)2[meia-C6H2(Me)2] (61mg, 0.06mmol) in carbon disulfide (20 ml) was

added dropwise over lh. The resultant solution was allowed to warm to room

temperature over a further lh, before being filtered through silica. The solvent was

removed under reduced pressure followed by product seperation by tic using hexane-

dichloromethane (1:1 v/v) as eluant. One major band was produced as well as some

cluster decomposition. The major band was extracted into dichioromethane and

characterised spectroscopically as 0s 3(CO)9(H)2 {C6H(Me)2(COMe) } 29 (yellow,

5%).

Spectroscopic data for 0s 3(C0)9(H)2 { C6H(Me)2(COMe) }: JR v(CO) 2108 (m), 2078 (s), 2054 (s),

2033 (m), 2023 (m), 2008 (m) cm'; MS: M += 972 (caic. 970) aniu

133

Chapter Five

Reaction of 0s 3(CO) 9(H)2('C61-13F) and 2-butyne

The compound 0s 3(CO)9(H)2(C6H3F) (42mg, 0.05mmol) and 2-butyne (2-3

drops excess) were dissolved in dichioromethane (50 ml). A solution of Me 3NO

(7mg, 2.2 mol. equiv.) in dichioromethane was added dropwise over lh. The resultant

solution was filtered through silica and the solvent was removed at reduced pressure.

The product was dissolved in dichloromethane and seperated by tic using hexane as

eluant. Two major bands were produced which were extracted into dichioromethane

and characterised spectroscopically as 0s 3 (CO)s(H)(CH2CHCHCH3)(C6H3F) 30 and

31 (yellow, 12% and 10%).

IR 30 v(CO) 2080 (m), 2049 (s), 2029 (m), 2000 (m), 1983 (w) cm -1 ; MS: M+= 945 (calc. 945)

JR 31 v(CO) 2081 (m), 2057 (sh), 2047 (s), 2029 (s), 1992 (m) cm'; MS: M += 953 (calc. 945)

Crystal measurement and details for 0s 3(CO)8(H)(CH2CHCHCH3)(C6H3F) 30: Formula C 1 8H11 080s3

M.Wt. 944.87 ainu, crystal size/mm 0.25 x 0.16 x 0. 16, crystal system Monoclinic, space group P-

2(1)/n, a= 15.131(5) A, b= 18.430(6) A, c= 15.297(5) A, 90 0 f3= 101.36(4) 0 -y= 90 0

Volume= 4182(2) A, Z= 8, F(000) 3360, pclr= 3.001 Mgm , ? (Mo-K)= 0.71073 A,

temperature 220(2) K, 20 range= 2.59 to 25.03 O measured reflections 9283, unique observed

reflections [I>2cr(I)] 7369, No. of refined parameters 553, goodness of fit on F 1.041, conventional

R [F>4(F)] R1= 0.0643, R indices (all data) R1 0.1356, wR2= 0. 1442.

134

Chapter Five

5.5 References

J. Cosier, A.M. Glaser, J. Appi. Crytallogr., 1986, 19, 105

G.M. Sheidrick, SHELXL 93, Program for crystal structural refinement, University of Gottingen, Germany, 1993

G.M. Sheidrick, SHELXTL PC, University of Gottingen and Siemens Analytical X-ray Instruments, Madison, 1990

A.G. Orpen, XHYDEX, Program for locating hydrides, Bristol University, 1980 see also: A.G. Orpen, J. Chem. Soc., Dalton Trans., 1980, 2509

W. de Graaf, J. Boersma, W.J.J. Smeets, A.L. Spek, G. van Koten, Organometallics, 1989, 8, 2907

W. de Graaf, J. Boersma, G. van Koten, Organometallics, 1990, 9, 1479

B.A. Markies, M.H.P. Rietveld, J. Boersma, A.L. Spek, G. van Koten, .1. Organomet. Chem., 1992, 424, Cl 2

135

0s3(CO)t-H)2(C6R31F)

Table 1. Crystal data and structure refinement for 0s3(C0)9(H)2(C6113})

Identification code si021

Empirical formula C15 H5 F 09 0s3

Formula weight 918.79

Temperature 293(2) K

Wavelength 0.71073 A Crystal system Monoclinic

Space group P2(1)/c

Unit cell dimensions a = 9.4776(8) A alpha =90 deg.

b = 10.429(2) A beta = 98.578(8) deg.

c = 20.023(2) A gamma =90 deg

Volume 1957.0(4) A Z 4

Density (calculated) 3.118 Mg/m'3

Absorption coefficient 19.482 mm"-1

F(000) 1616

Crystal size 0.36 x 0.32 x 0.24 mm

Theta range for data collection 2.06 to 30.00 deg.

Limiting indices -1<=h< 13, -1<=k<14, -28<I<28

Reflections collected 7334

Independent reflections 5713 [R(int) = 0.05321

Absorption correction Semi-empirical from psi-scans

Max. and mm. transmission 0.3420 and 0.2387

Refinement method Full-matrix least-squares on F'2

Data I restraints I parameters 5712/0/259

Goodness-of-fit on F"2 1.015

Final R indices [I>2sigma(1)] Ri = 0.0546, wR2 = 0.1092

R indices (all data) Ri =0.1073, wR2 = 0.1333

Largest duff, peak and hole 2.043 and -1.961 e.A"-3

Table 2. Atomic coordinates ( x 10"4) and equivalent isotropic displacement parameters (A"2 x 10'3) for 1. U(eq) is defined as one third of the trace of the orthogonalised Uij tensor

x y z U(eg) Os(1) 8185(1) 7231(1) 1834(1) 31(1)

8594(16) 5453(16) 1923(9) 54(4) 0(12) 8876(14) 4406(12) 1994(8) 82(4) C(11) 8324(15) 7727(15) 2767(7) 41(3) 0(11) 8454(13) 7972(15) 3322(6) 76(4)

10113(15) 7566(14) 1791(8) 42(3) 0(13) 11268(12) 7793(15) 1732(7) 76(4) Os(3) 5199(1) 7642(1) 1414(1) 31(1)

3917(15) 6199(16) 1362(8) 47(4) 0(31) 3139(14) 5349(13) 1309(7) 74(4) C(33) 4661(14) 8287(15) 2235(8) 46(4) 0(33) 4294(13) 8639(13) 2723(6) 66(3)

3860(19) 8747(16) 887(8) 56(4) 0(32) 3057(17) 9367(17) 582(9) 118(6) Os(2) 7296(1) 6881(1) 472(1) 37(1) C(21) 6439(21) 7392(18) -416(8) 62(5) 0(21) 5951(17) 7771(15) -928(6) 85(4) C(23) 6927(16) 5056(18) 418(9) 55(4) 0(23) 6714(15) 3986(13) 412(8) 82(4) C(22) 91 49(18) 6673(1 6) 240(8) 51(4) 0(22) 10274(14) 6573(16) 111(8) 92(5) F(1) 6194(12) 10529(10) 2157(5) 76(3)

7053(17) 10245(14) 1712(7) 44(3) C(2) 6852(14) 9035(14) 1402(7) 38(3) C(1) 7791(14) 8699(15) 902(6) 37(3) C(6) 8815(18) 9615(17) 756(8) 57(4)

8876(19) 10793(16) 1059(8) 57(4) 8008(20) 11116(15) 1546(9) 62(5)

Table 3. Bond lengths (A) and angles (deg) for 1.

Os(1)-C(13) 1.88(2) Os(1)-C(12) 1.90(2) Os(1)-C(11) 1.925(14) Os(1)-C(2) 2.358(13) Os(1)-C(1) 2.400(13) Os(1)-Os(2) 2.7554(8) Os(1)-Os(3) 2.8615(7) C(12)-0(12) 1.13(2) C(11)-0(11) 1.13(2) C(13)-0(13) 1.14(2) Os(3)-C(32) 1.91(2) Os(3)-C(33) 1.92(2) Os(3)-C(31) 1.93(2) Os(3)-C(2) 2.140(14) Os(3)-Os(2) 3.0417(8) C(31)-0(31) 1.15(2) C(33)-0(33) 1.14(2) C(32)-0(32) 1.11(2) Os(2)-C(22) 1.90(2) Os(2)-C(21) 1.92(2) Os(2)-C(23) 1.94(2) Os(2)-C(1) 2.11(2)

C(21)-0(21) 1.13(2) C(23)-0(23) 1.13(2) C(22)-0(22) 1.14(2)

F(1)-C(3) 1.33(2) C(3)-C(4) 1.36(2) C(3)-C(2) 1.41(2) C(2)-C(1) 1.48(2) C(1)-C(6) 1.42(2) C(6)-C(5) 1.37(2) C(5)-C(4) 1.41(2)

C(13)-Os(1)-C(12) 90.0(6) C(13)-Os(1)-C(1 1) 93.9(6) C(12).-Os(1)-C(1 1) 100.8(7) C(13)-Os(1)-C(2) 107.9(5) C(12)-Os(1)-C(2) 154.9(6) C(11)-Os(1)-C(2) 95.5(5) C(13)-Os(1)-C(1) 83.4(5) C(12)-.Os(1)-C(1) 134.7(6) C(11)-Os(1)-C(1) 124.3(6) C(2)-Os(1)-C(1) 36.2(5)

C(13)-Os(1)-Os(2) 97.8(5) C(12)-Os(1)-Os(2) 89.5(5) C(11)-Os(1)-Os(2) 164.4(4)

C(2)-Os(1)-Os(2) 71.0(3) C(1)-Os(1)-Os(2) 47.6(3)

C(13)-Os(1)-Os(3) 152.4(4) C(12)-Os(1)-Os(3) 110.7(5) C(11)-Os(1)-Os(3) 99.6(4) C(2)-Os(1)-Os(3) 47.2(3) C(1)-Os(1)-Os(3) 69.1(3) Os(2)-Os(1)-Os(3) 65.54(2) 0(12)-C(12)-Os(1) 178(2) O(11)-C(11)-Os(1) 176.6(14) 0(13)-C(13)-Os(1) 176.5(14) C(32)-Os(3)-C(33) 91.3(7) C(32)-Os(3)-C(31) 94.6(7) C(33)-Os(3)-C(31) 94.2(6) C(32)-Os(3)-C(2) 90.6(7) C(33)-Os(3)-C(2) 93.4(5) C(31)-Os(3)-C(2) 170.6(6) C(32)-Os(3)-Os(1) 143.0(6) C(33)-Os(3)-Os(1) 100.3(4) C(31)-Os(3)-Os(1) 119.2(5) C(2)-Os(3)-Os(1) 53.9(3)

C(32)-Os(3)-Os(2) 104.8(5) C(33)-Os(3)-Os(2) 155.0(4) C(31)-Os(3)-Os(2) 103.2(5) C(2)-Os(3)-Os(2) 67.9(4) Os(1)-Os(3)-Os(2) 55.55(2) 0(31)-C(31)-Os(3) 178(2) 0(33)-C(33)-Os(3) 177.2(13) 0(32)-C(32)-Os(3) 178(2) C(22)-Os(2)-C(21) 94.8(7) C(22)-Os(2)-C(23) 92.3(7) C(21)-Os(2)-C(23) 100.0(8) C(22)-Os(2)-C(1) 92.6(6) C(21)-Os(2)-C(1) 99.6(6) C(23)-Os(2)-C(1) 159.3(6) C(22)-Os(2)-Os(1) 95.8(5) C(21)-Os(2)-Os(1) 154.9(6) C(23)-Os(2)-Os(1) 102.2(5) C(1)-Os(2)-Os(1) 57.3(3) C(22)-Os(2)-Os(3) 153.8(5) C(21)-Os(2)-Os(3) 106.1(6) C(23)-Os(2)-Os(3) 99.3(5) C(1)-Os(2)-Os(3) 68.8(4) Os(1)-.Os(2)-Os(3) 58.91(2) 0(21)-C(21)Os(2) 176(2) 0(23)-C(23)-Os(2) 177(2) 0(22)-C(22)-Os(2) 178(2)

F(1)-C(3)-C(4) 121(2) F(1)-C(3)-C(2) 116.1(13)

C(4)-C(3)-C(2) 123(2) C(3)-C(2)-C(1) 117.1(13) C(3)-C(2)-Os(3) 131.0(11) C(1)-C(2)-Os(3) 111.2(10)

121.7(9) C(1)-C(2)-Os(1) 73.5(7) Os(3)-C(2)-Os(1) 78.9(5) C(6)-C(1)-C(2) 118.5(14) C(6)-C(1)-Os(2) 129.7(12) C(2)-C(1)-Os(2) 111.7(9) C(6)-C(1)-Os(1) 123.8(9) C(2)-C(1)-Os(1) 70.3(7) Os(2)-C(1)-Os(1) 75.1(5) C(5)-C(6)-C(1) 120(2) C(6)-C(5)-C(4) 122(2) C(3)-C(4)-C(5) 119(2)

Table 4. Anisotropic displacement parameters (A'2 x 10'3) for 1. The anisotropic displacement factor exponent takes the form: -2pi"2 [h"2 a*\2U11 +...+2hk a* b* U121

Ui! U22 U33 U23 U13 U12 Os(1) 26(1) 34(1) 33(1) 3(1) 2(1) 1(1)

42(8) 47(10) 76(11) 22(9) 19(8) 13(7) 0(12) 65(8) 45(8) 127(12) 14(8) -15(8) 17(6) C(11) 44(8) 44(8) 35(7) 3(6) 2(6) -3(7) 0(11) 66(8) 124(12) 39(6) -7(7) 13(6) 17(8)

32(7) 37(8) 53(9) -5(7) -5(6) 13(6) 0(13) 36(6) 119(12) 73(8) -9(8) 12(6) 8(7) Os(3) 26(1) 33(1) 34(1) 1(1) 2(1) 0(1)

42(8) 47(9) 55(9) 8(8) 18(7) -5(7) 0(31) 76(9) 63(8) 80(9) -3(7) 7(7) -27(7) C(33) 28(7) 47(9) 66(10) -9(8) 12(7) -11(6) 0(33) 68(8) 80(9) 57(7) -11(6) 35(6) 0(7)

63(10) 43(10) 58(10) 5(8) -.8(8) 17(8) 0(32) 95(11) 103(14) 138(14) 40(12) 41(10) 25(10) Os(2) 38(1) 39(1) 34(1) -5(1) 8(1) -6(1) C(21) 82(13) 69(12) 35(8) -9(8) 14(8) -21(10) 0(21) 105(12) 98(11) 45(7) 7(7) -11(7) 8(9) C(23) 41(9) 58(11) 65(11) -32(9) 3(8) -.6(8) 0(23) 82(9) 47(8) 119(12) -16(8) 21(8) -1(7) C(22) 55(9) 46(10) 54(9) 7(8) 15(8) -9(8) 0(22) 56(8) 114(13) 118(12) -28(10) 49(8) -1(8) F(1) 103(8) 58(7) 73(7) -18(5) 34(6) -10(6)

61(9) 34(8) 34(7) 6(6) 1(7) 1(7) C(2) 40(7) 38(8) 35(7) 5(6) 7(6) 8(6) C(1) 35(7) 51(9) 23(6) 6(6) -7(5) -6(6) C(6) 64(10) 56(11) 50(9) 12(8) 6(8) -26(9). C(S) 70(11) 39(9) 57(10) 13(8) -7(9) -12(8)

89(13) 31(8) 62(11) 1(8) -1(10) -28(9)

Table 5. Hydrogen coordinates (x 10"4) and isotropic displacement parameters (A"2 x 10'3) for 1.

x y z U(eg) H(6) 9442(18) 9414(17) 456(8) 68 11(5) 9511(19) 11400(16) 940(8) 69 H(4) 8088(20) 11918(15) 1751(9) 74 11(13) 6533(148) 7123(137) 2025(68) 50 11(23) 5477(147) 7041(135) 570(71) 50

Table 1. Crystal data and structure refinement for 0s 3(C0)9(ff)2(CJ13F)

Identification code siO21

Empirical formula C15 115 F 09 0s3


Temperature 293(2) K

Wavelength 0.71073 A

Crystal system Monoclinic

Space group P2(1)/c

Unit cell dimensions a = 9.4776(8) A alpha =90 deg.

b = 10.429(2) A beta 98.578(8) deg.

c = 20.023(2) A gamma =90 deg

Volume 1957.0(4) A

Z 4

Density (calculated) 3.118 Mg/m"3

Absorption coefficient 19.482 mm'-!

F(000) 1616

Crystal size 0.36 xO.32 x 0.24 mm


Limiting indices -1<=h< 13, -1(k<14, -28<1<28


Independent reflections 5713 [R(int) = 0.05321

Absorption correction Semi-empirical from psi-scans

Max. and mm. transmission 0.3420 and 0.2387

Refinement method Full-matrix least-squares on F A 2

Data I restraints / parameters 5712/0/259

Goodness-of-fit on F A 2 1.015

Final R indices [I>2sigma([)] Ri = 0.0546, wR2 = 0.1092

R indices (all data) RI = 0.1073, wR2 = 0.1333

Largest diff. peak and hole 2.043 and -1.961 e.A"-3

Table 2. Atomic coordinates ( x 10'4) and equivalent isotropic displacement parameters (A'2 x 10A3) for 1. U(eq) is defined as one third of the trace of the orthogonalised Uij tensor

z U(eg) Os(1) 8185(1) 7231(1) 1834(1) 31(1)

8594(16) 5453(16) 1923(9) 54(4) 0(12) 8876(14) 4406(12) 1994(8) 82(4) C(11) 8324(15) 7727(15) 2767(7) 41(3) 0(11) 8454(13) 7972(15) 3322(6) 76(4)

10113(15) 7566(14) 1791(8) 42(3) 0(13) 11268(12) 7793(15) 1732(7) 76(4) Os(3) 5199(1) 7642(1) 1414(1) 31(1)

3917(15) 6199(16) 1362(8) 47(4) 0(31) 3139(14) 5349(13) 1309(7) 74(4) C(33) 4661(14) 8287(15) 2235(8) 46(4) 0(33) 4294(13) 8639(13) 2723(6) 66(3)

3860(19) 8747(16) 887(8) 56(4) 0(32) 3057(17) 9367(17) 582(9) 118(6) Os(2) 7296(1) 6881(1) 472(1) 37(1) C(21) 6439(21) 7392(18) 416(8) 62(5) 0(21) 5951(17) 7771(15) -928(6) 85(4) C(23) 6927(16) 5056(18) 418(9) 55(4) 0(23) 6714(15) 3986(13) 412(8) 82(4) C(22) 9149(18) 6673(16) 240(8) 51(4) 0(22) 10274(14) 6573(16) 111(8) 92(5) F(1) 6194(12) 10529(10) 2157(5) 76(3)

7053(17) 10245(14) 1712(7) 44(3) C(2) 6852(14) 9035(14) 1402(7) 38(3) C(1) 7791(14) 8699(15) 902(6) 37(3) C(6) 8815(18) 9615(17) 756(8) 57(4)

8876(19) 10793(16) 1059(8) 57(4) 8008(20) 11116(15) 1546(9) 62(5)

Table 3. Bond lengths (A) and angles (deg) for 1.

Os(1)-C(13) 1.88(2) Os(1)-C(12) 1.90(2) Os(1)-C(11) 1.925(14) Os(1)-C(2) 2.358(13) Os(1)-C(1) 2.400(13) Os(1)-Os(2) 2.7554(8) Os(1)-Os(3) 2.8615(7) C(12)-0(12) 1.13(2) C(11)-0(11) 1.13(2) C(13)-0(13) 1.14(2) Os(3)-C(32) 1.91(2) Os(3)-C(33) 1.92(2) Os(3)-C(31) 1.93(2) Os(3)-C(2) 2.140(14) Os(3)-Os(2) 3.0417(8) C(31)-0(31) 1.15(2) C(33)-0(33) 1.14(2) C(32)-0(32) 1.11(2) Os(2)-C(22) 1.90(2) Os(2)-C(21) 1.92(2) Os(2)-C(23) 1.94(2) Os(2)-C(1) 2.11(2)

C(21)-.0(21) 1.13(2) C(23)-0(23) 1.13(2) C(22)-0(22) 1.14(2)

F(1)-C(3) 1.33(2) C(3)-C(4) 1.36(2) C(3)-C(2) 1.41(2) C(2)-C(1) 1.48(2) C(1)-C(6) 1.42(2) C(6)-C(5) 1.37(2) C(5)-C(4) 1.41(2)

C(13)-Os(1)-C(12) 90.0(6) C(13)-Os(1)-C(1 1) 93.9(6) C(12)-Os(1)-C(1 1) 100.8(7) C(13)-Os(1)-C(2) 107.9(5) C(12)-Os(1)-C(2) 154.9(6) C(11)-Os(1)-C(2) 95.5(5) C(13)-Os(1)-C(1) 83.4(5) C(12)-Os(1)-C(1) 134.7(6) C(1 1)-Os(1)-C(1) 124.3(6) C(2)-Os(1)-C(1) 36.2(5)

C(13)-Os(1)-Os(2) 97.8(5) C(12)-Os(1)-Os(2) 89.5(5) C(1i)-Os(1)-Os(2) 164.4(4)

C(2)-Os(1)-Os(2) 71.0(3) C(1)-Os(1)-Os(2) 47.6(3) C(13)-Os(1)-Os(3) 152.4(4) C(12)-Os(1)-Os(3) 110.7(5) C(1 1)-Os(1)-Os(3) 99.6(4) C(2)-Os(1)-Os(3) 47.2(3) C(1)-Os(1)-Os(3) 69.1(3) Os(2)-Os(1)-Os(3) 65.54(2) 0(12)-C(12)-Os(1) 178(2) O(11)-C(11)-Os(1) 176.6(14) 0(13)-C(13)-Os(1) 176.5(14) C(32)-Os(3)-C(33) 91.3(7) C(32)-Os(3)-C(31) 94.6(7) C(33)-Os(3)-C(31) 94.2(6) C(32)-Os(3)-C(2) 90.6(7) C(33)-Os(3)-C(2) 93.4(5) C(31)-Os(3)-C(2) 170.6(6) C(32)-Os(3)-Os(1) 143.0(6) C(33)-Os(3)-Os(1) 100.3(4) C(31)-Os(3)-Os(1) 119.2(5) C(2)-Os(3)-Os(1) 53.9(3)

C(32)-Os(3)-Os(2) 104.8(5) C(33)-Os(3)-Os(2) 155.0(4) C(31)-Os(3)-Os(2) 103.2(5) C(2)-Os(3)-Os(2) 67.9(4) Os(1)-Os(3)-Os(2) 55.55(2) 0(31)-C(31)-Os(3) 178(2) 0(33)-C(33)-Os(3) 177.2(13) 032)-C32)-Os(3) 178(2) C(22)-Os(2)-C(21) 94.8(7) C(22)-Os(2)-C(23) 92.3(7) C(21)-Os(2)-C(23) 100.0(8) C(22)-Os(2)-C(1) 92.6(6) C(21)-Os(2)-C(1) 99.6(6) C(23)-Os(2)-C(1) 159.3(6) C(22)-Os(2)-Os(1) 95.8(5) C(21)-Os(2)-Os(1) 154.9(6) C(23)-Os(2)-Os(1) 102.2(5) C(1)-Os(2)-Os(1) 57.3(3)

C(22)-Os(2)-Os(3) 153.8(5) C(21)-Os(2)-Os(3) 106.1(6) C(23)-Os(2)-Os(3) 99.3(5) C(1)-Os(2)-Os(3) 68.8(4) Os(1)-Os(2)-Os(3) 58.91(2) 0(21)-C(21)-Os(2) 176(2) 0(23)-C(23)-Os(2) 177(2) 0(22)-C(22)-Os(2) 178(2)

F(1)-C(3)-C(4) 121(2) F(1)-C(3)-C(2) 116.1(13)

C(4)-C(3)-C(2) 123(2) C(3)-C(2)-C(1) 117.1(13) C(3)-C(2)-Os(3) 131.0(11) C(1)-C(2)-Os(3) 111.2(10) C(3)-C(2)-Os(1) 121.7(9) C(1)-C(2)-Os(1) 73.5(7) Os(3)-C(2)-Os(1) 78.9(5) C(6)-C(1)-C(2) 118.5(14) C(6)-C(1)-Os(2) 129.7(12) C(2)-C(1)-Os(2) 111.7(9) C(6)-C(1)-Os(1) 123.8(9) C(2)-C(1)-Os(1) 70.3(7) Os(2)-C(1)-Os(1) 75.1(5) C(5)-C(6)-C(1) 120(2) C(6)-C(5)-C(4) 122(2) C(3)-C(4)-C(5) 119(2)

Table 4. Anisotropic displacement parameters (A'2 x 10"3) for 1. The anisotropic displacement factor exponent takes the form: -2 piA2 [h"2 a*2 Ull +...+ 2 h k a* b* U121

Ull U22 U33 U23 U13 U12 Os(1) 26(1) 34(1) 33(1) 3(1) 2(1) 1(1)

42(8) 47(10) 76(11) 22(9) 19(8) 13(7) 0(12) 65(8) 45(8) 127(12) 14(8) -15(8) 17(6) C(11) 44(8) 44(8) 35(7) 3(6) 2(6) -3(7) 0(11) 66(8) 124(12) 39(6) -7(7) 13(6) 17(8)

32(7) 37(8) 53(9) -5(7) -5(6) 13(6) 0(13) 36(6) 119(12) 73(8) -9(8) 12(6) 8(7) Os(3) 26(1) 33(1) 34(1) 1(1) 2(1) 0(1)

42(8) 47(9) 55(9) 8(8) 18(7) -5(7) 0(31) 76(9) 63(8) 80(9) -3(7) 7(7) -27(7) C(33) 28(7) 47(9) 66(10) -9(8) 12(7) -11(6) 0(33) 68(8) 80(9) 57(7) -11(6) 35(6) 0(7)

63(10) 43(10) 58(10) 5(8) -8(8) 17(8) 0(32) 95(11) 103(14) 138(14) 40(12) 41(10) 25(10) Os(2) 38(1) 39(1) 34(1) -5(1) 8(1) -6(1) C(21) 82(13) 69(12) 35(8) -9(8) 14(8) -21(10) 0(21) 105(12) 98(11) 45(7) 7(7) -11(7) 8(9) C(23) 41(9) 58(11) 65(11) -32(9) 3(8) -6(8) 0(23) 82(9) 47(8) 119(12) -16(8) 21(8) -1(7) C(22) 55(9) 46(10) 54(9) 7(8) 15(8) -9(8) 0(22) 56(8) 114(13) 118(12) -28(10) 49(8) -1(8) F(1) 103(8) 58(7) 73(7) -18(5) 34(6) -10(6)

61(9) 34(8) 34(7) 6(6) 1(7) 1(7) C(2) 40(7) 38(8) 35(7) 5(6) 7(6) 8(6) C(1) 35(7) 51(9) 23(6) 6(6) -7(5) -6(6) C(6) 64(10) 56(11) 50(9) 12(8) 6(8) -26(9)

70(11) 39(9) 57(10) 13(8) -7(9) -12(8) 89(13) 31(8) 62(11) 1(8) -1(10) -28(9)

Table 5. Hydrogen coordinates (x 10''4) and isotropic displacement parameters (A¼2 x 10"3) for 1.

x y z U(eg) 11(6) 9442(18) 9414(17) 456(8) 68 11(5) 9511(19) 11400(16) 940(8) 69 11(4) 8088(20) 11918(15) 1751(9) 74

11(13) 6533(148) 7123(137) 2025(68) 50 11(23) 5477(147) 7041(135) 570(71) 50

Jk'-. .,

Table 1. Crystal data and structure refinement for clbos3 at 150(2) K.

Empirical formula C15 ff5 Cl 09 0s3



Crystal system Triclinic

Space group P-i

Unit cell dimensions a = 8.666(5) A alpha = 100.04(3) deg. b = 9.309(5) A beta = 97.27(2) deg. c = 14.107(8) A ga = 116.83(3) deg.

Volume 972.3(9) A*3

Z 2

Density (calculated) 3.194 Mg/m^3

Absorption coefficient 19.736 mm-1

F(000) 824

Crystal description Yellow block



Index ranges -10<=h(=10, -11<k<10, 0<1<16


Independent reflections 3444 (R(int) = 0.0686]

Scan type

Absorption correction Difabs (Tmin= 0.827, Tmax=1.337)

Data / restraints / parameters 3441/0/255 (Full-matrix least-squares on F

Goodness-of-fit on F2 1.027

Conventional R [F>4sigma(F)] RI = 0.0365 [2876 data]

R indices (all data) Ri = 0.0502, wR2 = 0.0883

Extinction coefficient 0.0010(2)

Final maximum delta/sigma 0.001

Weighting scheme calc where P=(Fo2+2Fc2)/3

Largest diff. peak and hole 1.702 and -1.681 e.A-3

Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (A2 x 103) for 1. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.

z y z U(eq)

1539(1) 998(1) 7989(1) 27(1) 3069(1) 22(1) 6596(1) 21(1)

08(3) 399(1) -2632(1) 7173(1) 26(1) Cl(l) 5965(5) 3511(4) 9684(3) 49(1)

5357(15) 1450(14) 9021(9) 28(3) 6509(16) 907(18) 9164(10) 40(3) 6062(17) -734(17) 8666(10) 37(3) 4447(17) -1742(15) 8015(9) 31(3) 3186(14) -1168(13) 7882(8) 23(2) 3612(15) 472(15) 8390(8) 25(2)

3053(20) 3219(17) 7994(11) 45(4) 0(11) 3953(19) 4579(13) 7958(9) 72(4)

1171(17) 1543(16) 9290(10) 36(3) 0(12) 1046(14) 1897(13) 10072(7) 52(3)

-453(22) 964(19) 7215(11) 45(4) 0(13) -1704(16) 873(17) 6720(9) 70(3)

5304(18) 1948(15) 6909(8) 30(3) 0(21) 6703(12) 3130(11) 7113(7) 46(3)

3731(17) -1317(17) 5718(10) 37(3) 0(22) 4081(15) -2162(13) 5208(8) 53(3)

2250(15) 929(16) 5692(9) 28(3) 0(23) 1811(13) 1565(12) 5184(7) 46(2)

614(18) -4438(16) 6414(11) 43(4) 0(31) 687(15) -5516(12) 5959(8) 56(3)

-29(16) -3741(14) 8234(9) 30(3) 0(32) -158(13) -4376(11) 8841(7) 43(2)

-2143(19) -3592(18) 6542(11) 46(4) 0(33) -3571(13) -4064(14) 6196(9) 63(3)

Table 3. Bond lengths [A] and angles [deg] for 1.

Os(1)-C(11) 1.882(14) Os(1)-C(13) 1.91(2) Os(1)-C(12) 1.924(13) Os(1)-C(6) 2.102(11) Os(l)-Os(2) 2.7502(13) Os(l)-Os(3) 3.010(2) 0s(2)-C(23) 1.880(13) Os(2)-C(21) 1.880(13) Os(2)-C(22) 1.92(2) Os(2)-C(5) 2.298(11) Os(2)-C(6) 2.439(11) Os(2)-Os(3) 2.852(2) Os(3)-C(31) 1.93(2) 09(3)-C(32) 1.943(13) Os(3)-C(33) 1.97(2) 08(3)-C(5) 2.152(11) C1(1)-C(1) 1.780(12) C(1)-C(2) 1.32(2) C(1)-C(6) 1.43(2) C(2)-C(3) 1.41(2) C(3)-C(4) 1.37(2) C(4)-C(5) 1.42(2) C(5)-C(6) 1.42(2) C(11)-0(11) 1.16(2) C(12)-0(12) 1.13(2) C(13)-0(13) 1.17(2) C(21)-0(21) 1.166(14) C(22)-0(22) 1.14(2) C(23)-0(23) 1.14(2) C(31)-0(31) 1.13(2) C(32)-0(32) 1.112(14) C(33)-0(33) 1.12(2)

C(11)-Os(1)-C(13) C(11)-Os(1)-C(12) C(13)-Os(1)-C(12) C(11)-Os(1)-C(6) C(13)-Os(1)--C(6) C(12)-Os(1)-C(6) C(11)-Os(1)-Os(2) C(13)-Os(1)-Os(2) C(12)-08(1)-Os(2) C(6)-Os(1)-Os(2) C (11)-Os (1)-Os (3) C(13)-Os(1)-Os(3) C(12)-Os(1)-Os(3) C(6)-Os(1)-Os(3) Os(2)-Os(1)-Os(3) C(23)-Os(2)-C(21) C(23)-Os(2)-C(22) C(21)-Os(2)-C(22) C(23)-Os(2)-C(5) C(21)-Os(2)-C(5) C(22)-Os(2)-C(5) C(23)-Os(2)-C(6) C(21)-Os(2)-C(6) C(22)-Os.(2)-C(6) C(5)-Os(2)-C(6) C(23)-0B(2)-Os(1) C(21)-0S(2)-OS(1)

92.1(7) 95.1(5) 99.7(6) 94.9(6)

160.5(5) 97.9(5) 88.0(4)

103.6(4) 156.4(4) 58.5(3)

147.2(4) 96.2(5)

114.5(4) 68.5(3) 59.16(3) 88.4(5) 99.7(5) 94.6(5)

159.6(4) 103.9(4) 95.5(5)

134.8(4) 82.9(4)

125.1(5) 34.8(4) 91.4(3) 99.9(4)

C(22)-Os(2)-Os(1) C(5)-Os(2)-Os(1) C(6)-Os(2)-Os(1) C(23)-Os(2)-Os(3) C(21)-Os(2)-Os(3) C(22)-Os(2)-Os(3) C(5)-Os(2)-Os(3) C(6)-Os(2)-Os(3) Os(1)-Os(2)-Os(3) C(31)-Os(3)-C(32) C(31)-Os(3)-C(33) C(32)-Os(3)-C(33) C(31)-Os(3)-C(5) C(32)-Os(3)-C(5) C (33)-Os (3)-C (5) C(31)-Os(3)-Os(2) C(32)-Os(3)-Os(2) C(33)-Os(3)-Os(2) C(5)-Os(3)-Os(2) C(31)-Os(3)-Os(1) C(32)-Os(3)-Os(1) C(33)-08(3)-Os(1) C(5)-Os(3)-Os(1) 09(2)-Os(3)-Os(1) C(2)-C(1)-C(6) C(2)-C(1)-C1(1) C(6)-C(1)-C1(1) C(1)-C(2)-C(3) C(4)-C(3)-C(2) C(3)-C(4)-C(5) C(6)-C(5)-C(4) C(6)-C(5)-Os(3) C(4)-C(5)-Os(3) C(6)-C(5)-Os(2) C (4)-C(S)-Os (2) Os(3)-C(5)-Os(2) C(5)-C(6)-C(1) C(S)-C(6)-Os(l) C(1)-C(6)-Os(1) C(5)-C(6)-Os(2) C (1)-C (6) -Os (2) Os(1)-C(6)-Os(2) O(11)-C(11)-Os(1) 0(12)-C(12)-Os(1) 0(13)-C(13)-Os(1) 0(21)-C (21)-Os (2) 0(22)-C(22)-Os(2) 0(23)-C(23)-Os(2) 0(31)-C (31)-Os (3) 0(32)-C(32)-Os(3) 0(33)-C(33)-Os(3)

162.0(4) 70.7(3) 47.3(3)

116.2(4) 150.2(3) 97.3(4) 47.9(3) 67.9(3) 64.96(4) 89.6(5) 93.8(6) 94.8(5) 94.8(5) 90.5(5)

169.9(6) 97.8(4)

142.6(3) 121.0(4) 52.4(3)

153.4(4) 109.1(3) 102.9(5) 67.2(3) 55.88(4)

124.2(12) 118.4(10) 117 .3(9) 120.1(12) 119.9(12) 119.8(11) 120.7(10) 111.0(8) 127 .4(8) 78.0(6)

118.5(8) 79.6(4)

115.1(10) 111.9(8) 132.9(9) 67.2(6)

122.3(8) 74.1(3)

177(2) 176.4(12) 177 .2(14) 178.8(11) 177.4(11) 176.0(11) 178.0(13) 174.8(12) 176.8(14)

Symmetry transformations used to generate equivalent atoms:

Table 4. Anisotropic displacement parameters (A'2 x 10'3) for 1. The anisotropic displacement factor exponent takes the form: -2 pi2 [ h2 a*2 Ull + ... + 2 h k a* b* U12 1

1.111 U22 U33 1123 U13 U12

30(1) 31(1) 29(1) 11(1) 13(1) 21(1) 21(1) 23(1) 22(1) 8(1) 7(1) 11(1) 23(1) 24(1) 26(1) 8(1) 7(1) 7(1)

C1(1) 45(2) 37(2) 43(2) -7(2) 2(2) 11(2) 21(6) 29(6) 27(6) 4(5) 6(5) 7(5) 21(6) 63(9) 40(8) 21(7) 8(6) 20(6) 33(7) 51(8) 40(8) 19(6) 9(6) 29(6) 46(8) 28(6) 38(7) 20(5) 21(6) 28(6) 18(5) 23(6) 31(6) 11(5) 4(5) 11(4) 27(6) 40(7) 24(6) 17(5) 12(5) 25(5)

65(10) 41(8) 58(9) 16(7) 42(8) 43(7) 0(11) 121(11) 33(6) 79(9) 21(6) 50(8) 43(7)

30(7) 40(7) 37(8) 11(6) 18(6) 14(6) 0(12) 57(7) 69(7) 39(6) 10(5) 19(5) 36(6)

65(10) 57(9) 39(8) 22(7) 35(8) 41(8) 0(13) 62(8) 109(10) 63(8) 20(7) 15(6) 63(8)

51(8) 29(6) 13(5) 6(4) 7(5) 23(6) 0(21) 40(5) 28(5) 45(6) 1(4) 12(4) -1(4)

37(7) 46(8) 30(7) 19(6) 13(6) 18(6) 0(22) 73(7) 53(6) 44(6) 10(5) 34(6) 35(6)

20(6) 44(7) 24(6) 2(5) 1(5) 23(5) 0(23) 43(6) 54(6) 48(6) 29(5) 9(5) 25(5)

31(7) 26(7) 48(8) 13(6) -1(6) -5(6) 0(31) 73(8) 32(5) 57(7) -2(5) 12(6) 25(5)

30(6) 28(6) 26(6) 0(5) -5(5) 14(5) 0(32) 51(6) 47(6) 33(5) 27(4) 14(4) 17(5)

28(8) 45(8) 51(9) 15(7) 9(6) 5(6) 0(33) 28(6) 67(7) 73(8) 31(6) 1(5) 3(5)

Table S. Hydrogen coordinates ( x 104) and isotropic displacement parameters (A'2 x 103) for 1.

x y z U(eq)

H(13) -48(1) -1153(1) 7995(1) 54(30) H(23) 767(1) -1728(1) 6101(1) 54(30) E(2) 7642(16) 1618(18) 9603(10) 48

6881(17) -1136(17) 8783(10) 45 4169(17) -2823(15) 7651(9) 37

Table 1. Crystal data and structure refinement for 3.

Identification code

Empirical formula

Formula weight

Temperature

Wavelength

Crystal system

Space group

Unit cell dimensions

Volume

os3tol

C16 H8 09 0s3

914.82

150 (2) K

0.71073 A

Triclinic

p-i

a = 9.260(2) A b = 13.115(2) A c = 16.633(3) A

2014.1(6) AA3

alpha.= 91.01(2) deg. beta .= 93.58(2) deg gamma = 92.23(2) deg

z

Density (calculated)

Absorption coefficient

F(000)

Crystal size

Theta range for data collection

Index ranges

Reflections collected

Independent reflections

Max. and mm. transmission

Refinement method

Data / restraints / parameters

Goodness-of-fit on F2

Final P. indices EI>2sigma(I)]

R indices (all data)

Largest diff. peak and hole

4

3.017 Mg/m""3

18.923 mm"'-1

1616

0.43 x 0.23 x 0.19 mm

2.59 to 27.53 deg.

-12<=h<=12, -17<=kcz=17, 0<=1<=21

9479

9234 [R(int) = 0.10361

0.037 and 0.007

Full-matrix least-squares on

9234 / 0 / 505

1.008

Ri = 0.0503, wR2 = 0.1215

Ri = 0.0786, wR2 = 0.1358

2.629 and -2.432 e.AA_3

Table 2. Atomic coordinates and equivalent isotropic displacement parameters (A2) for 1. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.

x y

VA

U(eq)

Os (1)

C(ll)

0(11) 0(12) 0(13) 0(21) 0(22) 0(23) 0(31) 0(32) 0(33) Os (4) Os(5) Os (6)

0(41) 0(42) 0(43) 0(51) 0(52) 0(53) 0(61)

0.00524(6) 0.30493(6) 0.23234(6)

-0.128(2) -0.126(2) -0.050(2) 0.369(2) 0.498(2) 0.297(2) 0.429(2) 0.191(2) 0.174(2) 0.262(2) 0.369(2) 0.370(2) 0.273(2) 0.181(2) 0.172(2) 0.474(2)

-0.2078(14) -0.1952(12) -0.0866(13) 0.407(2) 0.6141(13) 0.293(2) 0.5473 (14) 0.156(2) 0.1401(13) 0.18424(6) 0.48486(6) 0.25148(6) 0.116(2)

-0.008(2) 0.196(2) 0.610(2) 0.623(2) 0.545(2) 0.281(2) 0.313(2) 0.052(2) 0.229(2) 0.134(2) 0.137(2) 0.231(2) 0.323(2) 0.3.24 (2) 0.042(2) 0.0700 (14)

-0.1218(12) 0.2032 (14) 0.685(2) 0.7040 (14) 0.580(2) 0.303 (2)

0.28213 (4) 0.32711(4) 0.12338(4) 0.2521(10) 0.2354(11) 0.4196(12) 0.3037(13) 0.3295(11) 0.4718(13) 0.0904(12) 0.0741(11) 0.0029(11) 0.2294(11) 0.2271(12) 0.2995 (12) 0.3829(12) 0.3883 (12) 0.3076(10) 0.2953(13) 0.2416(9) 0.2034(9) 0.5021(8) 0.2910 (12) 0.3313(9) 0.5613 (8) 0.0697(10) 0.0497 (10)

-0.0704(9) 0.19575(4) 0.23378(4) 0.38207(4) 0.2510(11) 0.1759 (11) 0.0579(12) 0.3072 (12) 0.2429(11) 0.1040 (13) 0.4727(12) 0.4771(11) 0.4097 (13) 0.2493 (10) 0.2242(10) 0.1343 (13) 0.0572 (14) 0.0743(11) 0.1723(11) 0.109(2) 0.2862(9) 0.1626(9)

-0.0247(9) 0.3481(11) 0.2427(10) 0.0246(10) 0.5186(11)

0.39981(3) 0.43887(3) 0.40738(4) 0.3091(10) 0.4815 (10) 0.4068(9) 0.5474(11) 0.4101(9) 0.4411(10) 0.4162(11) 0.5131(10) 0.3473(8) 0.3134(9) 0.2523 (10) 0.1956(10) 0.2000 (10) 0.2600(9) 0.3202(9) 0.1302 (10) 0.2536(8) 0.5283(8) 0.4092 (7) 0.6125(8) 0.3897(7) 0.4454(8) 0.4204(9) 0.5747(8) 0.3105(7) 0.80842(3) 0.85053(3) 0.88328(4) 0.7114(10) 0.8402(8) 0.7668(10) 0.7789(10) 0.9411(11) 0.8189(11) 0.7938(11) 0.9685(11) 0.8869(13) 0.9513(8) 1.0097(10) 1.0498(9) 1.0245(10) 0.9632(9) 0.9252(9) 1.1170(12) 0.6517(8) 0.8614(8) 0.7457 (8) 0.7372(9) 0.9947(8) 0.7966(10) 0.7389(10)

0.03260 (13) 0.03348(13) 0.03382 (13) 0.040(3) 0.044(4) 0.041(3) 0.048(4) 0.039(3) 0.046(4) 0.045(4) 0.043(3) 0.038(3) 0.038(3) 0.044(4) 0.041(3) 0.049(4) 0.041(3) 0.035(3) 0.047(4) 0.056(3) 0.053(3) 0.051(3) 0.072(4) 0.052(3) 0.061(3) 0.063(3) 0.063(4) 0.051(3) 0.03324(13) 0.03461(13) 0.03594 (14) 0.042(3) 0.036(3) 0.045(4) 0.044(3) 0.042(4) 0.050(4) 0.051(4) 0.047(4) 0.056(5) 0.033(3) 0.039(3) 0.044(4) 0.050(4) 0.039(3) 0.037(3) 0.067(6) 0.056(3) 0.053(3) 0.056(3) 0.068(4) 0.062(3) 0.071(4) 0.081(5)

0(62) 0.3446(13) 0.5288(9) 1.0230(8) 0.052(3)

0(63) -0.067(2) 0.4260(11) 0.8886(12) 0.084(5)

Table 3. Selected bond lengths [A] and angles [deg] for 1.



Os(l)-C(13) 1.90(2) Os(1)-C(11) 1.91(2) Os(l)-C(12) 1.97(2) Os(1)-C(76) 2.11(2) Os(l)-Os(2) 2.8470(10) Os(1) -Os (3) 3.0147(9) Os(2)-C(22) 1.88(2) Os(2)-C(21) 1.90(2) Os(2)-C(23) - 1.90(2) Os(2)-C(76) 2.27(2) Os(2)-C(71) 2.432(14) Os(2)-Os(3) 2.7627(9) Os(3)-C(31) 1.89(2) Os(3)-C(33) 1.90(2) Os(3)-C(32) 1.94(2) Os(3)-C(71) 2.13(2) C(11)-0(11) 1.15(2) C(12)-0(12) 1.12(2) C(13)-0(13) 1.15(2) C(21)-0(21) 1.14(2) C(22)-0(22) 1.14(2) C(23)-0(23) 1.18(2) C(31)-0(31) 1.13(2) C(32)-0(32) 1.14(2) C(33)-0(33) 1.15(2) C(71) -C(76) 1.36(2) C(71)-C(72) 1.46(2) C(72)-C(73) 1.35(2) C(73)-C(74) 1.45(2) C(73)-C(77) 1.50(2) C(74)-C(75) 1.36(2) C(75) -C(76) 1.47(2) Os(4)-C(41) 1.87(2) Os(4)-C(42) 1.90(2) Os(4)-C(43) 1.93(2) Os(4)-C(86) 2.30(2) Os(4)-C(81) 2.472(13) Os(4)-Os(6) 2.7544(9) Os(4)-Os(5) 2.8503(10) Os(5)-C(53) 1.89(2) Os(5)-C(52) 1.91(2) Os(5)-C(51) 1.95(2) Os(5)-C(86) 2.14(2) Os(5)-Os(6) 3.0308(10) Os(6)-C(63) 1.91(2) Os(6)-C(62) 1.92(2) Os(6)-C(61) 1.95(2) Os(6)-C(81) 2.104(13) C(41)-0(41) 1.17(2) C(42)-0(42) 1.14(2) C(43)-0(43) 1.14(2) C(51)-0(51) 1.14(2) C(52)-0(52) 1.13(2) C(53)-0(53) 1.16(2) C(61)-O(61) 1.13(2) C(62)-0(62) 1.14(2) C(63)-0(63) 1.13(2) C(81)-C{82) 1.38(2) C(81) -C(86) 1.45(2) C(82)-C(83) 1.37(2)

C(83) -C(84) -C(87) -C(85) -C(86)

C(13) -Os(1) -C(11) C(13) -Os(1) -C(12) C(11) -Os (1)-C(12) C(13) -Os(1) -C(76) C(11) -Os(1) -C(76) C(12) -Os (1)-C(76) C (13) -Os (1) -Os (2)

-Os(1) -Os(2) -Os (1) -Os (2)

C(76) -Os(1) -Os(2) -Os(1) -Os(3)

C(11) -Os(1) -Os (3) C(12) -Os(1) -Os(3) C(76) -Os (1) -Os (3) Os (2) -Os(1) -Os(3) C(22) -Os (2) -C(21) C(22) -Os(2) -C(23) C(21) -Os (2) -C(23) C(22) -Os(2) -C(76) C(21) -Os(2) -C(76) C(23)-Os(2) -C(76) C (22) -Os (2) -C (71) C(21) -Os(2) -C(71) C(23) -Os (2) -C(71) C(76) -Os (2) -C(71) C(22) -Os(2) -Os(3) C(21) -Os (2) -Os(3) C(23) -Os (2) -Os (3) C(76) -05(2) -Os(3) C(71)-Os(2) -Os(3)

-Os(2) -Os(1) C (21) -Os (2) -Os (1)

-Os (2) -Os (1) C(76) -05(2) -Os(1) C(71) -Os (2), -Os (1) Os (3) -Os (2) -Os (1) C(31) -Os (3)-C(33) C(31) -Os(3) -C(32)

-05(3) -C(32) -05(3) -C(71)

C(33) -Os(3) -C(71) -Os (3) -C(71)

C (31) -Os (3) -Os (2) -Os (3) -Os (2)

C(32)-Os(3) -Os(2) C(71) -Os(3) -Os(2)

-Os (3) -Os (1) C (33) -Os (3)-Os (1)

-Os(3) -Os(1) C(71) -Os (3) -Os(1) Os(2) -Os(3) -Os(1) O(11)-C(11) -Os(1) 0(12) -C(12) -Os ('1) 0(13) -C(].3) -Os (1) 0(21) -C(21) -Os (2) 0(22) -C (22) -Os (2) 0(23) -C(23) -Os (2) 0(31) -C(31) -Os(3) 0(32) -C(32) -Os(3)

1.44(2) 1.50(2) 1.38(2) 1.44(2)

92.7(6). 93.8(6) 95.7(7) 96.4(6) 89.3(6)

168.4(6) 95.1(5)

141.0(5) 121.7(5) 51.9(4)

151.2(5) 109.0(4) 102.4(4) 66.1(4) 56.15(2) 89.8(7) 93.3(7)

100.4(7) 104.6(6) 158.9(6) 94.3(5) 83.1(6)

138.0(6) 121.2(6) 33.3(4) 99.2(4) 93.2(5)

161.5(4) 69.5(3) 48.0(4)

150.2(4) 115.1(5) 97.6(5) 47.2(4) 67.5(4) 65.00(2) 93.7(7) 94.7(7) 97.7(6) 93.7(6)

101.3(5) 158.6(6) 91.1(5)

158.9(4) 102.3(4) 57.9(4)

149.6(5) 112.8(5) 96.1(4) 67.5(4) 58.85(2)

175.0(12) 175.5(14) 177.8(14) 179(2) 177.5(13) 178(2) 179 (2) 173.8(14)

0(33) -C(33) -Os(3) C(76) -C(71) -C(72) C(76) -C(71) -Os (3) C(72) -C(71) -Os (3) C(76) -C(71) -Os (2)

-C(71) -Os(2) Os (3) -C(71) -Os (2)

-C(72) -C(71) C(72) -C(73) -C(74) C(72)-C(73)-C(77) C(74)-C(73)-C(77) C(75)-C(74)-C(73) C(74)-C(75)-C(76) C(71) -C(76) -C(75) C(71)-C(76)-Os(1) C(75) -C(76) -Os(1) C(71) -C(76) -Os(2) C(75)-C(76) -Os(2) OS (1) -C(76) -Os (2) C(41) -Os (4) -C(42)

-Os (4) -C(43) C(42)-Os(4)-C(43) C(41)-Os(4)-C(86)

-Os(4) -C(86) -Os(4) -C(86) -Os (4)-C(81) -OS (4)-C(81)

C(43)-Os(4)-C(81) C(86) -Os (4) -C(81)

-OS (4) -Os (6) -Os(4) -Os(6) -Os(4) -Os(6)

C(86)-Os(4) -Os(6) C(81) -Os(4) -Os(6) C (41) -Os (4) -Os (5) C(42) -Os(4) -Os(5) C(43) -Os(4) -Os(5) C(86) -Os (4) -Os (5) C(81) -Os (4) -Os(5) Os(6) -Os(4) -Os(5) C(53)-Os(5)-C(52) C (53) -Os (5) -C(51) C (52) -Os (5) -C(51) C(53)-Os(5) -C(86) C(52) -Os(5) -C(86) C(51) -Os (5) -C(86) C(53) -Os(5) -Os(4)

-Os (5) -OS (4) C(51) -OS (5) -OS (4) C(86)-Os(5) -05(4)

-Os (5) -Os (6) C (52) -Os (5) -Os (6) C(51)-Os(5)-Os(6) C(86) -Os (5) -Os (6) OS (4) -Os(5) -Os(6) C(63) -Os(6) -C(62) C(63)-Os(6) -C(61)

-Os(6) -C(61) -Os (6) -C(81) -Os (6)-C(81)

C(61)-Os(6)-C(81) -Os(6) -Os(4)

C(62) -Os (6) -OS (4) C(61) -Os (6) -Os (4)

179 .2(14) 122 .2(14) 110.1(11) 127.6(10) 66.6(8)

122.2(11) 74.1(4)

119.8(14) 119 (2) 120.4(14) 120.3(14) 121 (2) 121 (2) 116.5(14) 114.8(11) 127.2(11) 80.0(9)

118.9(10) 81.0(5) 90.8(7) 95.8(7) 94.2(6)

160.7(6) 103.6(6) 95.9(7)

138.6(6) 82.1(5)

125.2(6) 35.1(5) 94.7(5) 98.9(4)

163.0(5) 70.6(3) 47.1(3)

115.3(5) 149.6(4) 97.9(5) 47.6(4) 68.2(3) 65.44(3) 92.7(7) 94.1(7) 94.5(7) 93.6(6) 90.2(6)

170.8(6) 96.4(5)

142.0(5) 121.3(5) 52.5(4)

151.8(5) 106.9(4) 104.2(5) 66.8(4) 55.75(2) 94.5(7) 93.9(8) 97.4(7) 92.4(7) 99.2(6)

161.8(6) 91.2(5)

158.1(5) 103.4(5)

C(81) -Os (6) -Os(4) 59.4(4) C(63) -Os (6) -OS (5) 149.5(5) C(62) -Os (6) -OS (5) 111.6(5) C(61) -Os (6) -05(5) 98.0(6) C (81) -Os (6) -Os (5) 68.8(4) Os(4) -Os (6) -Os (5) 58.80(2) 0(41) -C(41) -Os (4) 178 (2) O(42)-C(42)-Os(4) 177.9(14) 0(43)-C(43)-Os(4) 177(2) 0(51) -C(51) -Os (5) 178 (2) O(52)-C(52)-Os(5) 176.2(14) 0(53)-C(53)-Os(5) 178(2) O(61)-C(61)-Os(6) 174(2) O(62)-C(62)-Os(6) 174.8(13) O(63)-C(63)-Os(6) 180(2) C(82)-C(81)-C(86) 118.3(13) C(82)-C(81)-Os(6) 130.9(11) C(86)-C(81)-Os(6) 110.6(9) C(82)-C(81)-Os(4) 122.8(10) C(86)-C(81)-Os(4) 65.9(8) Os(6)-C(81) -OS (4) 73.5(4) C(83) -C(82) -C(81) 123.3(14) C(82)-C(83)-C(84) 119(2) C(82)-C(83)-C(87) 124(2) C(84)-C(83)-C(87) 117(2) C(85)-C(84)-C(83) 121(2) C(84)-C(85)-C(86) 119(2) C(85)-C(86)-C(81) 119.4 (13) C(85)-C(86)-Os(5) 127.0(11) C(81)-C(86)-Os(5) 112.1(9) C(85) -C(86) -Os(4) 120.4 (10) C(81)-C(86)-Os(4) 79.0(8) Os(5)-C(86) -Os(4) 79.8(5)


Table 5. Anisotropic displacement parameters (A2) for 1. The anisotropic displacement factor exponent takes the form: -2 pi"2 E h"2 a*A2 Ui]. + . . . + 2 h k a* b* U12

Ui]. tJ22 U33. U23 U13 1J12

)s(1) 0.0315(3) 0.0333(3) 0.0332(3) 0.0013(2) 0.0024(2) 0.0029(2) )s(2) 0.0324(3) 0.0358(3) 0.0321(3) -0.0008(2) 0.0029(2) -0.0004(2) )s(3) 0.0346(3) 0.0325(3) 0.0347(3) 0.0027(2) 0.0029(2) 0.0030(2) :(l1) 0.045(8) 0.022(6) 0.053(10) -0.006(6) 0.003(7) 0.003(5)

0.048(9) 0.034(7) 0.049(10) -0.003(6) -0.004(7) 0.010(6) 0.045(9) 0.045(8) 0.033(8) 0.015(6) -0.008(6) 0.008(6) 0.045(9) 0.051(9) 0.047(10) -0.001(7) 0.017(7) -0.016(7) 0.043(9) 0.037(7) 0.036(8) -0.001(6) -0.008(6) 0.005(6) 0.037(8) 0.060(10) 0.039(9) 0.008(7) -0.017(7) 0.008(7)

:31) 0.038(8) 0.041(8) 0.056(10) 0.007(7) 0.006(7) 0.004(6) 0.046(9) 0.030(7) 0.052(10) 0.010(6) 0.008(7) 0.005(6) 0.061(10) 0.039(7) 0.018(6) 0.015(5) 0.010(6) 0.009(6) 0.040(8) 0.041(7) 0.031(7) -0.001(6) -0.013(6) 0.015(6) 0.038(8) 0.049(9) 0.046(9) -0.005(7) -0.001(7) 0.016(6)

'(73) 0.033(8) 0.044(8) 0.045(9) -0.001(7) -0.004(6) -0.003(6) 0.064(11) 0.048(9) 0.035(8) 0.011(7) 0.003(7) -0.010(8) 0.042(8) 0.045(8) 0.035(8) -0.001(6) 0.000(6) 0.001(6) 0.040(8) 0.031(6) 0.033(7) 0.001(5) 0.003(6) 0.000(5) 0.048(9) 0.051(9) 0.043(9) -0.001(7) 0.007(7) 0.001(7) 0.057(8) 0.048(6) 0.061(8) -0.005(6) -0.015(6) 0.009(5) 0.038(6) 0.067(8) 0.058(8) 0.013(6) 0.018(6) 0.001(5) 0.062(8) 0.038(6) 0.053(7) -0.005(5) 0.003(6) 0.005(5) 0.071(9) 0.110(12) 0.032(7) 0.006(7) -0.011(6) -0.013(8) 0.042(7) 0.071(8) 0.045(7) 0.013(6) 0.007(5) 0.007(5) 0.077(9) 0.035(6) 0.069(9) -0.005(6) 0.001(7) -0.011(6) 0.050(8) 0.073(9) 0.069(9) 0.007(7) 0.006(6) 0.018(6) 0.081(10) 0.061(8) 0.050(8) 0.022(6) 0.019(7) 0.019(7) 0.059(8) 0.049(6) 0.045(7) -0.004(5) -0.002(6) 0.001(5)

)s(4) 0.0352(3) 0.0334(3) 0.0310(3) 0.0009(2) 0.0018(2) -0.0011(2) )s(5) 0.0339(3) 0.0360(3) 0.0341(3) 0.0000(2) 0.0040(2) 0:0008(2) )s(6) 0.0383(3) 0.0311(3) 0.0382(3) 0.0005(2) 0.0010(2) 0.0015(2)

0.048(9) 0.035(7) 0.044(9) 0.005(6) 0.004(7) -0.005(6) 0.043(8) 0.037(7) 0.029(7) 0.002(5) 0.008(6) -0.005(6) 0.044(9) 0.050(9) 0.045(9) -0.005(7) 0.027(7) -0.004(7)

:(51) 0.039(8) 0.048(8) 0.044(9) 0.002(7) -0.003(7) 0.002(6) 0.036(8) 0.037(7) 0.054(10) -0.008(7) 0.016(7) 0.005(6) 0.050(10) 0.047(9) 0.053(10) 0.003(7) 0.015(8) -0.016(7) 0.056(11) 0.042(8) 0.053(11) 0.005(8) -0.021(8) -0.004(7) 0.041(8) 0.036(7) 0.067(11) -0.009(7) 0.042(8) -0.015(6) 0.058(12) 0.041(9) 0.069(13) 0.010(8) -0.006(9) 0.004(8) 0.039(7) 0.036(7) 0.023(6) -0.001(5) 0.005(5) -0.004(5) 0.037(8) 0.033(7) 0.047(9) -0.003(6) 0.007(6) -0.002(6) 0.045(9) 0.056(9) 0.030(8) 0.016(7) -0.002(6) -0.003(7) 0.049(10) 0.057(10) 0.042(9) 0.002(7) 0.003(7) -0.007(7)

:(85) 0.049(9) 0.034(7) 0.035(8) 0.007(6) -0.007(6) 0003(6) 0.045(8) 0.035(7) 0.031(7) 0.003(5) 0.004(6) 0.000(6) 0.066(13) 0.077(13) 0.059(12) 0.004(10) 0.026(10) -0.023(10) 0.062(8) 0.055(7) 0.051(7) 0.011(6) -0.002(6) -0.008(6) 0.040(6) 0.058(7) 0.061(8) -0.007(6) 0.012(6) -0.008(5) 0.070(8) 0.042(6) 0.056(8) -0.008(5) 0.001(6) -0.002(5) 0.061(8) 0.084(10) 0.059(9) 0.010(7) 0.010(7) -0.020(7) 0.051(7) 0.081(9) 0.053(8) -0.016(7) -0.016(6) 0.012(6) 0.067(9) 0.062(8) 0.085(11) -0.028(7) 0.005(8) 0.020(7)

)(61) 0.105(12) 0.059(8) 0.074(10) 0.020(8) -0.025(9) -0.021(8)

0.045(7) 0.049(6) 0.061(8) -0.015(6) 0.007(6) 0.001(5) 0.045(8) 0.067(9) 0.14(2) 0.015(9) 0.006(9) 0.023(7)

Table 6. Hydrogen coordinates and isotropic displacement parameters (AA2) for ]

x y

U(eq)

H(72)

H(77A) H(77B) H(77C) H(82)

H(87A) H(87B) H(87C)

0.436(2) 0.274(2) 0.123(2) 0.461(2) 0.457(2) 0.572(2) 0.065(2) 0.230(2) 0.383(2) 0.063(2) -0.058(2) 0.059(2)

0.1760(12) 0.4331(12) 0.4443 (12) 0.3522(13) 0.2328(13) 0.2982 (13) .0.2709(10) -0.0055(14) 0.0236 (11) 0.042(2) 0.109(2) 0.158(2)

0.2525 (10) 0.1612 (10) 0.2635(9) 0.0953 (10) 0.0996(10) 0.1538(10) 1.0219 (10) 1.0498 (10) 0.9468(9) 1.1362 (12) 1.0974(12) 1.1603 (12)

0.053 0.059 0.049 0.071 0.071 0.071 0.047 0.060 0.047 0.101 0.101 0.101

Table 1. Crystal data and structure refinement for nol98la at 150(2) K.

Empirical formula C17 510 09 0s3




Space group P-i

Unit cell dimensions a = 8.873(11) A alpha = 79.95(7) deg. b = 9.708(8) A beta = 73.56(8) deg. c = 13.644(12) A ga-ma = 64.88(8) deg.

Volume 1019(2) A3

2 2

Density (calculated) 3.028 Mg/m3

Absorption coefficient 18.710 mm-1

F(000) 824

Crystal description Yellow plate developed in (011)



Index ranges -8<h<9, -10<k<10, 0<=l<=14


Independent reflections 2333 [R(int) = 0.0822]

Scan type omega-theta

Absorption correction Psi-scans (Tmin= 0.277, Tmax=0.722)



Conventional R (F>4sigma(F)J Ri = 0.0451 (1815 data]

R indices (all data) Ri = 0.0660, wR2 = 0.1143


Weighting scheme calc w=i/[\s'2(Fo'2')+(0.0709P)'2'+0.8654P] where P=(Fo2+2FC'2')/3


Table 2. Atomic coordinates ( x 10'4) and equivalent isotropic displacement parameters (A2 x 103) for 1. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.

x y z U(eq)

Os(l) -125(1) 4147(1) 2358(1) 16(1) 154(1) 1190(1) 2949(1) 18(1) 2363(1) 2448(1) 3561(1) 18(1) -1106(27) 4291(24) 1272(15) 21(5)

0(11) -1703(19) . 4379(17) 601(11) 30(4) 276(28) 6019(27) 1877(16) 25(5)

0(12) 496(20) 7090(18) 1613(11) 32(4) -2295(30) 5131(27) 3257(16) 23(5)

0(13) -3551(21) . 5678(19) 3846(12) 37(4) -1158(28) 1095(26) 2092(16) 24(5)

0(21) -1958(28) 1034(24) 1603(13) 62(7) 1409(31) -991(30) 3073(16) 29(5)

0(22) 2175(23) -2229(20) 3149(13) 48(5) -1718(33) 1410(30) 4158(18) 35(6)

0(23) -2926(22) 1671(23) 4811(12) 50(5) 3576(29) 3729(27) 3373(16) 28(5)

0(31) 4376(24) 4411(22) 3240(14) 52(5) 4375(30) 653(27) 3596(15) 23(5)

0(32) 5599(20) -408(19) 3615(12) 38(4) 1589(29) 2562(27) 5058(17) 28(5)

0(33) 1109(21) 2674(20) 5905(10) 37(4) 1791(25) 1763(23) 1666(14) 16(4) 2162(26) 1529(24) 599(14) 20(5) 3478(26) 1800(24) -101(14) 18(4)

C(30) 3800(28) 1495(26) -1233(15) 25(5) 4323(27) 2581(25) 148(15) 22(5)

c(40) 5796(31) 2843(29) -643(17) 36(6) 4014(26) 2831(24) 1154(15) 22(5) 2703(24) 2476(22) 1960(14) 14(4)


Os(1)-C(11) 1.88(2) Os(1)-C(13) 1.91(2) Os(1)-C(12) 1.97(2) Os(1)-C(6) 2.30(2) 08(1)-C(1) 2.38(2) Os(1)-Os(2) 2.766(3) Os(1)-Os(3) 2.881(4) Os(2)-C(21) 1.91(2) Os(2)-C(22) 1.93(3) Os(2)-C(23) 1.95(2) Os(2)-C(1) 2.10(2) Os(2)-Os(3) 3.056(3) Os(3)-C(32) 1.90(3) Os(3)-C(31) 1.91(2) Os(3)-C(33) 1.97(2) Os(3)-C(6) 2.12(2) C(l1)-0(11) 1.15(2) C(12)-0(12) 1.12(2) C(13)-0(13) 1.14(3) C(21)-0(21) 1.13(2) C(22)-0(22) 1.10(3) C(23)-0(23) 1.15(3) C(31)-0(31) 1.12(2) C(32)-0(32) 1.14(3) C(33)-0(33) 1.12(2) C(1)-C(6) 1.43(3) C(1)-C(2) 1.44(3) C(2)-C(3) 1.37(3) C(3)-C(4) 1.40(3) C(3)-C(30) 1.55(3) C(4)-C(5) 1.37(3) C(4)-.C(40) 1.53(3) C(5)-C(6) 1.47(3)

C(11)-Os(1)-C(13) C(11)-Os(1)-C(12) C(13)-Os(1)-C(12) C(11)-Os(1)-C(6) C(13)-Os(1)-C(6) C(12)-Os(1)-C(6) C(11)-Os(1)-C(1) C(13)-Os(1)-C(1) C(12)-Os(1)-C(1) C (6)-Os (1) -C (1) C(11)-Os(1)-0S(2) C(13)-Os(1)-0S(2) C(12)-Os(1)-Os(2) C(6)-0S(1)-0S(2) C(1)-Os(1)-OS(2) C (11)-Os (1)-Os (3) C(13)-Os(1)-Os(3) C(12)-Os(1)-Os(3) C(6)-Os(1)-Os(3). C(1)-Os(1)-Os(3) Os(2)-Os(1)-Os(3) C(21)-Os(2)-C(22) C(21)-Os(2)-C(23) C(22)-O8(2)-C(23) C(21)-Os(2)-C(1) C(22)-0S(2)C(1)

93.0(9) 93.2(8) 95.1(9)

108.4(8) 154.9(7) 96.5(8) 81.7(8)

142.8(8) 121.8(8) 35.6(6) 93.1(6) 96.7(6)

166.3(7) 69.9(4) 47.3(4)

150.4(7) 108.9(6) 104.0(6) 46.6(5) 68.9(5) 65.50(8) 94.5(10) 91.8(9) 99.0(10) 90.2(8)

100.2(9)

C(23)-Os(2)-C(1) C(21)-Os(2)-Os(1) C(22)-Os(2)-Os(1) C(23)-06(2)-Os(1) C(1)-Os(2)-Os(1) C(21)-Os(2)-Os(3) C(22)-Os(2)-Os(3) C(23)-Os(2)-Os(3) C( 1)-Os (2)-Os (3) Os(1)-Os(2)-Os(3) C (32 ) -Os (3)-C (31) C(32)-Os(3)-C(33) C(31)-Os(3)-C(33) C(32)-Os(3)-C(6) C (31)-Os (3)-C (6) C(33)-Os(3)-C(6) C(32)-Os(3)-Os(1) C(31) -Os (3 )-Os ( 1) C(33) -Os (3 )-Os ( 1) C(6)-Os(3)-Os(1) C(32)-Os(3)-Os(2) C(31)-Os(3)-08(2) C(33)-Os(3)-Os(2) C(6)-Os(3)-08(2) Os(1)-Os(3)-Os(2) 0(11)-C(11)-Os(1) 0(12)-C(12)-Os(1) 0(13)-C(13)-Os(1) 0(21) -C (21) -Os (2) 0(22)-C(22)-Os(2) 0(23)-C(23)-Os(2) 0(31)-C(31)-Os(3) 0(32)-C(32)-Os(3) 0(33)-C(33)-Os(3) C (6)-C (1)-C (2) C (6)-C (1)-Os (2) C (2) -C (1)-Os (2) C(6)-C(1)-Os(1) C(2)-C(1)-Os(1) Os(2)-C(1)-Os(1) C(3)-C(2)-C(l) C(2)-C(3)-C(4) C(2)-C(3)-C(30) C(4)-C(3)-C(30) C(S)-C(4)-C(3) C(5)-C(4)-C(40) C(3)-C(4)-C(40) C(4)-C(S)-C(6) C(1)-C(6)-C(5) C ( 1)-C (6)-Os (3) C(5)-C(6)-Os(3) C(1)-C(6)-Os(1) C(5)-C(6)-Os(1) Os(3)-C(6)-Os(1)

160.4(9) 97.3(6)

153 .8(6) 103.9(8) 56.6(6)

154.0(6) 103.4(6) 103 .6(7) 68.4(5) 59.06(7) 92.2(9) 95.0(9) 95.0(9) 93.6(8) 91.0(8)

169.3(8) 142.8(6) 101.4(7) 117.7(7) 52.2(5)

100.8(6) 154. 1(6) 105.9(6) 66.1(5) 55.44(7)

180(2) 179 (2) 176 (2) 179 (2) 177 (2) 173(2) 176 (2) 179(2) 178(2) 117 (2) 110.9(13) 131.8(14) 69.4(12)

122.0(14) 76.1(7)

122(2) 122(2) 118(2) 119(2) 118(2) 121(2) 120(2) 123(2) 118(2) 114.2(12) 126.9(13) 75.0(12)

122.9(13) 81.2(7)


Table 4. Anisotropic displacement parameters (A'2 x 10'3) for 1. The anisotropic displacement factor exponent takes the form: -2 pi2 [ h2 a*2 Ull + ... + 2 h k a* b* U12 ]

Ull 1722 U33 U23 U13 U12

15(1) 19(1) 18(1) -2(1) -4(1) -9(1) 18(1) 20(1) 20(1) 0(1) -3(1) -12(1) 18(1) 21(1) 19(1) -2(1) -7(1) -10(1)

0(11) 33(10) 24(9) 35(9) 1(7) -15(7) -11(8) 0(12) 39(10) 30(10) 36(9) -2(8) 1(7) -28(9) 0(13) 33(10) 34(10) 43(9) -15(8) 4(8) -15(9) 0(21) 109(17) 97(17) 40(10) 11(11) -38(11) -91(16) 0(22) 51(13) 25(11) 59(11) 2(9) -11(9) -11(10) 0(23) 31(11) 75(15) 31(9) -6(9) 13(8) -22(11) 0(31) 60(13) 51(13) 69(12) -4(10) -21(10) -41(12) 0(32) 24(10) 31(11) 44(10) 1(8) -3(8) 0(9) 0(33) 51(12) 54(12) 17(8) -10(8) -11(7) -27(11)

Table S. Hydrogen coordinates ( x 104) and isotropic displacement parameters (A2 x 103) for 1.

x y z U(eq)

H(13) 507(1) 4282(1) 3511(1) 50 H(23) 1292(1) 1102(1) 3919(1) 50 E(2) 1478(26) 1178(24) 370(14) 23 H(30A) 4864(87) 594(88) -1416(32) 37 H(30B) 3896(166) 2380(63) -1674(16) 37 H(30C) 2843(81) 1316(145) -1326(25) 37 H(40A) 5341(34) 3633(128) -1161(68) 54 H(40B) 6580(107) 1892(54) -973(85) 54 H(40C) 6414(126) 3170(172) -304(26) 54 H(5) 4674(26) 3254(24) 1342(15) 26

Table 1. Crystal data and structure refinement for os3xyl at 150(2) K.

Empirical formula C17 H10 09 0s3




Space group P-i

Unit cell dimensions a = 8.257(3) A alpha = 90.70(3) deg. b = 9.114(4) A beta = 100.92(4) deg. c = 14.771(6) A gm = 109.80(3) deg.

Volume 1023.4(7) A3

Z 2

Density (calculated) 3.014 Ng/m3

Absorption coefficient 18.623 am-1

F(000) 824

Crystal description Yellow chip



Index ranges -11<=hc=11, -12<k<12, 0<=l<=20



Scan type omega-theta

Absorption correction Psi-scans (Tmin= 0.034, Tnax=0.069)

Data / restraints I parameters 5980/0/265 (Full-matrix least-squares on F - :


Conventional R (F)4sigaa(F)] RI = 0.0442 (4611 data]




Weighting scheme calc w1/(\s2(Fo2)+(0.0638P) 2+0.0000P] where P=(Fo2'+2Fc2)/3


Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (A2 x 103) for 1. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.

X 7 z U(eq)

8064(1) 1739(1) 3333(1) 21(1) 6437(1) 3810(1) 2705(1) 21(1) 4303(1) 506(1) 3055(1) 21(1)

5855(13) 568(12) 2065(7) 25(2) 6709(12) 2115(11) 1803(6) 22(2) 7586(14) 2294(13) 1031(7) 27(2)

C(3M) 8448(17) 3867(14) 695(9) 39(3) 7532(15) 937(14) 572(7) 31(2) 6725(14) -583(13) 793(7) 28(2)

C(5M) 6765(16) -1960(13) 239(8) 34(2) 5917(14) -753(12) 1533(7) 30(2)

10183(15) 2802(13) 2953(8) 30(2) 0(11) 11503(11) 3465(11) 2722(7) 47(2)

8964(15) 2737(12) 4547(8) 29(2) 0(12) 9398(13) 3331(11) 5277(6) 44(2)

8536(13) -197(12) 3511(7) 26(2) 0(13) 8831(13) -1304(11) 3604(7) 46(2)

6436(14) 4849(13) 3872(8) 31(2) 0(21) 6519(13) 5438(11) 4573(6) 45(2)

8548(14) 5451(12) 2611(7) 27(2) 0(22) 9792(11) 6421(10) 2522(6) 40(2)

4903(15) 4614(12) 1890(7) 29(2) 0(23) 3981(12) 5025(11) 1362(6) 41(2)

2130(15) -41(14) 2134(8) 32(2) 0(31) 924(12) -348(12) 1574(6) 43(2)

3260(14) 856(13) 4077(8) 29(2) 0(32) 2705(13) 1134(11) 4674(6) 42(2)

4014(13) -1659(10) 3265(7) 22(2) 0(33) 3846(13) -2896(11) 3425(7) 48(2)

Table 3. Bond lengths [A] and angles (deg] for 1.

08(l)-C(11) 1.885(11) 09(l)-C(12) 1.895(11) Os(1)-C(13) 1.942(10) 05(l)-C(l) 2.306(10) Os(1)-C(2) 2.408(9) Os(l)-Os(2) 2.7425(12) Os(l)-Os(3) 2.8666(13) Os(2)-C(22) 1.904(10) 0s(2)-C(23) 1.913(11) Os(2)-C(21) 1.956(12) Os(2)-C(2) 2.123(10) Os(2)-Os(3) 3.0379(15) Os(3)-C(33) 1.941(9) Os(3)-C(31) 1.942(12) Os(3)-C(32) 1.948(11) Os(3)-C(1) 2.108(10) C(1)-C(2) 1.441(14) C(1)-C(6) 1.451(15) C(2)-C(3) 1.445(13) C(3)-C(4) 1.39(2) C(3)-C(3M) 1.51(2) C(4)-C(5) 1.39(2) C(5)-C(6) 1.368(15) C(5)-C(5M) 1.504(14) C(11)-0(11) 1.170(13) C(12)-0(12) 1.136(13) C(13)-0(13) 1.120(13) C(21)-0(21) 1.141(14) C(22)-0(22) 1.137(12) C(23)-0(23) 1.142(13) C(31)-0(31) 1.117(14) C(32)-0(32) 1.130(13) C(33)-0(33) 1.122(12)

C(11)-Os(1)-C(12) C(11)-Os(1)-C(13) C(12)-Os(1)-C(13) C(11)-Os(1)-C(1) C(12)-Os(1)-C(1) C(13)-Os(1)-C(1) C(11)-Os(1)-C(2) C(12)-Os(1)-C(2) C(13)-Os(1)-C(2) C(1)-Os(1)-C(2) C(11)-Os(1)-Os(2) C(12)-Os(1)-Os(2) C(13)-Os(1)-08(2) C(1)-Os(1)-Os(2) C (2) -Oi (1)-Os (2) C(1l)-Os(1)-Os(3) C(12)-Os(1)-Os(3) C(13)-Os(1)-Os(3) C(1)-Os(1)-Os(3) C(2)-Os( 1)-Os (3) Os(2)-Os(1)-09(3) C(22)-Os(2)-C(23) C(22)-Os(2)-C(21) C(23)-Os(2)-C(21) C(22)-Os(2)-C(2) C(23)-Os(2)-C(2)

92.2(5) 95.0(4)

100.3(4) 110.2(4) 154.0(4) 91.0(4) 84.1(4)

142.0(4) 117.7(4) 35.5(3) 95.4(3) 95.0(3)

161.2(3) 70.7(3) 48.2(2)

152.7(3) 108.1(4) 98.9(3) 46.6(3) 68.7(2) 65.54(3) 95.5(5) 89.7(4) 98.6(5) 96.6(4)

101.5(4)

C(21)-Os(2)-C(2) C(22)-Os(2)-Os(1) C(23)-09(2)-Os(1) C(21)-Oé(2)-Os(1) C(2)-Os(2)-Os(1) C(22)-08(2)-09(3) C(23)-Os(2)-Os(3) C(21)-Os(2)-Os(3) C (2) -Os (2) -Os (3) Os(1)-Os(2)-Os(3) C(33)-Os(3)-C(31) C(33)-08(3)-C(32) C(31)-Os(3)-C(32) C (33) -Os (3)-C (1) C(31)-Os(3)-C(1) C(32)-Os(3)-C(1)

-O (3)-Os ( 1) -Os (3)-Os ( 1) -Os (3)-Os ( 1)

C(1)-Os(3)-Os(1) C(33)-Os(3)-Os(2) C(31)-Os(3)-Os(2) C(32)-Os(3)-Os(2) C(1)-Os(3)-Os(2) Os(1)-Os(3)-Os(2) C (2)-C (1) -C (6) C (2)-C() -Os (3) C (6)-C (1)-Os (3) C(2)-C(1)-Os(1) C(6)-C(1)-08(1) Os(3)-C(].)-Os(1) C(1)-C(2)-C(3) C(1)-C(2)-Os(2) C(3)-C(2)-Os(2) C(1)-C(2)-09(1) C(3)-C(2)-Os(l) Os(2)-C(2)-Os(1) C(4)-C(3)-C(2) C(4)-C(3)-C(3M) C(2)-C(3)-C(3M) C(3)-C(4)-C(5) C(6)-C(S)-C(4) C(6)-C(5)-C(5M) C(4)-C(5)-C(5M) C(S)-C(6)-C(I) 0(11)-C(11)-08(1) 0(12)-C(12)-Os(l) 0(13)-C(13)-Os(1) 0(21)-C (21) -Os (2) 0(22)-C(22)-Os(2) 0(23)-C(23)-Os(2) 0(31) -C (31)-Os (3) 0(32)-C(32)-Os(3) 0(33)-C(33)-Os(3)

158.2(4) 95.1(3)

157.6(3) 101. 1(3) 57.7(2)

154.2(3) 107.8(3) 97.4(3) 68.4(3) 59.20(3) 93.6(5) 95.3(4) 94.8(5) 92.6(4) 93.7(4)

168.0(4) 98.5(3)

144.4(3) 117.1(3) 52.6(3)

152.9(3) 104.8(4) 102.6(3) 66.9(3) 55.26(3)

117.9(9) 114.0(7) 127 .3(7) 76.1(5)

119.5(7) 80.9(3)

119.4(9) 109.7(7) 130.9(7) 68.3(5)

122.6(7) 74.2(3)

117.1(10) 120.4(10) 122.4(10) 125.9(10) 117.1(10) 122.3(10) 120.6(10) 122.6(10) 179.7(10) 175.7(11) 178.7(10) 176.1(10) 177.6(10) 175.7(10) 176.8(10) 176.6(10) 177.0(10)


Table 4. Anisotropic displacement parameters (A2 x 103) for 1. The anisotropic displacement factor exponent takes the form: -2 pi2 ( h2 a*2 Ull + ... + 2 h k a* b* U12 I

Ull U22 U33 U23 U13 U12

08(1) 17(1) 20(1) 24(1) 2(1) 3(1) 5(1) 19(1) 18(1) 26(1) 2(1) 5(1) 5(1) 17(1) 20(1) 24(1) 3(1) 5(1) 3(1)

20(4) 24(5) 25(5) -3(4) 2(4) 1(4) 21(4) 22(5) 22(4) 7(3) 3(3) 7(4) 24(5) 30(5) 25(5) 2(4) 7(4) 6(4)

C(3M) 44(7) 35(6) 39(6) 6(5) 18(5) 9(5) 36(6) 36(6) 27(5) 4(4) 11(4) 16(5)

C(S) 23(5) 27(5) 30(5) -10(4) 6(4) 4(4) C(5M) 36(6) 27(6) 36(6) -8(4) 11(5) 4(5) C(6) 28(5) 21(5) 30(5) -2(4) 4(4) -3(4)

33(6) 29(5) 34(5) 10(4) 8(4) 17(5) 0(11) 22(4) 50(6) 72(7) 14(5) 20(4) 12(4)

36(6) 20(5) 34(6) 2(4) 1(4) 15(4) 0(12) 49(5) 41(5) 31(4) -7(4) -5(4) 9(4)

23(5) 21(5) 37(5) 9(4) 10(4) 8(4) 0(13) 57(6) 34(5) 59(6) 13(4) 24(5) 26(4)

22(5) 30(6) 39(6) 0(5) 5(4) 4(4) 0(21) 47(5) 46(5) 43(5) -12(4) 16(4) 14(4)

25(5) 24(5) 30(5) 1(4) 9(4) 2(4) 0(22) 32(4) 29(4) 50(5) -2(4) 15(4) -4(3)

33(5) 20(5) 32(5) 7(4) 11(4) 4(4) 0(23) 44(5) 41(5) 37(4) 14(4) -1(4) 18(4)

33(6) 32(6) 31(5) -2(4) 8(5) 11(5) 0(31) 34(5) 57(6) 36(4) 1(4) 2(4) 15(4)

28(5) 28(5) 33(5) 8(4) 10(4) 11(4) 0(32) 55(6) 51(6) 32(4) 10(4) 22(4) 25(5)

23(4) 10(4) 28(5) 3(3) 1(4) 1(3) 0(33) 48(6) 29(5) 62(6) 10(4) 12(5) 9(4)

Table S. Hydrogen coordinates ( x 104) and isotropic displacement parameters (A2 x 103) for 1. H(l) and H(2) were placed by the program HYDEX.

x y z U(eq)

H(l) 6282(1) 811(1) 3942(1) 50 H(2) 4304(1) 2488(1) 2872(1) 50 H(3M1) 9596(53) 4397(47) 1102(38) 59 8(3)(2) 7702(58) 4504(41) 702(59) 59 H(3M3) 8607(110) 3725(16) 63(25) 59 H(4) 8097(15) 1054(14) 60(7) 37 H(5M1) 7967(27) -1771(47) 156(53) 51 H(5M2) 5978(91) -2103(66) -368(25) 51 H(5M3) 6375(114) -2904(23) 567(31) 51 H(6) 5374(14) -1778(12) 1705(7) 36

Table 1. Crystal data and structure refinement for os3fme at 220(2) K.

Empirical formula C18 Ell F 08 0s3



Crystal system Monoclinic

Space group P2(1)/n

Unit cell dimensions a = 15.131(5) A alpha = 90 deg. b = 18.430(6) A beta = 101.36(4) deg. c = 15.297(5) A gamon = 90 deg.

Volume 4182(2) A3

Z 8

Density (calculated) 3.001 Mg/m3

Absorption coefficient 18.234 aa-1

F(000) 3360

Crystal description block Yellow

Crystal size 0.25 x 0.16 x 0.16 ma


Index ranges -18c=hc=17, 0c=kc=21, 0c=lc=18



Scan type omega-theta with learnt profile

Absorption correction Psi-scans + Difabs (Tain= 0.028, Taax=0.074)



Conventional R (F)4sigma(F)] RI = 0.0643 [4240 data]




Weighting scheme caic w=l/(\s'2'(Fo'2')+(0.0327P)^2+71.3486P] where P=(F o 2*+2Fc 2)/3


Table 2 • Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (A'2 x 103) for 1. U(eq) is defined as one third of the trace of the orthogonalized Uij tensor.

x y z U(eq)

08(1) 6987(1) 9466(1) 6622(1) 45(1) Os(2) 7156(1) 10731(1) 7948(1) 49(1) 09(3) 8522(1) 10354(1) 7091(1) 46(1) C(1) 8046(16) 9897(14) 8351(14) 43(6) C(2) 8686(19) 9783(17) 9177(19) 61(8) F(2) 8705(12) 10324(12) 9813(11) 99(6) C(3) 9184(17) 9200(17) 9398(19) 63(8) C(4) 9210(20) 8653(17) 8804(23) 78(10) C(5) 8647(16) 8734(15) 7925(19) 57(8) C(6) 8097(16) 9349(15) 7712(20) •62(8) C(7) 5519(19) 9267(18) 6054(20) 71(9) C(8) 5857(25) 8709(25) 6603(25) 113(15) C(9) 6313(20) 8663(19) 7473(23) 74(10) C(10) 6686(24) 8121(23) 8008(31) 154(22) C(11) 6882(17) 10128(16) 5676(21) 61(8) 0(11) 6758(15) 10499(13) 5031(14) 99(9) C(21) 7488(16) 8778(14) 5986(18) 49(7) 0(21) 7865(14) 8312(12) 5651(15) 83(6) C(12) 7850(19) 11428(16) 8658(20) 65(9) 0(12) 8274(16) 11877(11) 9103(14) 82(7) C(22) 6367(20) 10549(13) 8727(18) 62(8) 0(22) 5914(14) 10408(12) 9240(13) 81(7) C(32) 6459(19) 11447(15) 7190(20) 58(8) 0(32) 6022(16) 11875(12) 6729(19) 105(9) C(13) 8271(20) 11211(18) 6358(20) 67(9) 0(13) 8146(17) 11688(12) 5913(14) 93(8) C(23) 9260(16) 9817(14) 6433(17) 49(7) 0(23) 9700(14) 9543(13) 5986(13) 85(7) C(33) 9496(26) 10797(17) 7759(17) 79(11) 0(33) 10073(14) 11094(13) 8246(14) 87(7) Os(4) 6483(1) 8302(1) 1728(1) 52(1) 08(5) 7850(1) 7065(1) 1822(1) 56(1) 09(6) 7018(1) 7395(1) 3210(1) 47(1)

8272(19) 7894(15) 2763(18) 55(7) 9127(26) 7966(20) 3356(20) 84(11)

F(2') 9788(20) 7499(19) 3391(24) 75(11) 9309(20) 8559(18) 3900(19) 66(8) 8684(20) 9086(18) 3962(19) 69(9) 7890(21) 9029(13) 3396(17) 49(7)

P(5') 7206(32) 9509(29) 3414(37) 160(21) 7612(20) 8412(16) 2785(16) 59(8) 5840(33) 8474(23) 242(28) 127(16) 6313(28) 9059(24) 612(24) 100(13) 7208(24) 9128(16) 1025(19) 65(8)

7682(24) 9755(21) 1426(24) 112(14) C(14) 5558(20) 7579(19) 1668(25) 86(11) 0(14) 4941(16) 7211(14) 1536(16) 100(8) C(24) 5822(15) 8928(13). 2271(19) 52(7) 0(24) 5447(12) 9362(10) 2649(13) 70(6) C(1S) 8578(20) 6362(17) 2479(23) 74(10) 0(15) 9040(17) 5911(14) 2878(20) 120(10) C(25) 8614(21) 7264(18) 1068(23) 85(11) 0(25) 9085(14) 7364(12) 524(14) 84(7) C(35) 7052(26) 6357(16) 1109(23) 77(11)

0(35) 6573(15) 5928(12) 778(16) 78(7) C(16) 6336(23) 6531(16) 3005(20) 70(10) 0(16) 5935(14) 5993(11) 2832(17) 86(7) C(26) 6387(19) 7891(18) 3937(16) 68(9)

0(26) 5903(14) 8156(12) 4399(13) 83(7)

C(36) 7781(19) 6968(14) 4160(21) 62(8)

0(36) 8310(13) 6724(12) 4751(14) 78(6)


Os(1)-C(21) 1.85(3) Os(1)-C(11) 1.88(3) 09(1)-C(6) 2.13(3) 08(1)-C(8) . 2.20(3) Os(1)-C(7) 2.25(3) 08(1)-C(9) 2.33(3) Os(1)-0s(3) . 2.816(2) Os(l)-Os(2) 3.067(2) 0s(2)-C(12) . 1.87(3) 09(2)-C(22) 1.88(3) 0s(2)-C(32) .1.93(3) Os(2)-C(i) 2.06(3) Os(2)-Os(3) 2.745(2) Os(3)-C(33) 1.81(3) 09(3)-C(23) 1.92(3) Os(3)-C(13) 1.93(3) 0s(3)-C(6) 2.23(3) Os(3)-C(1) 2.34(2) C(1)-C(6) 1.42(3) C(1)-C(2) 1.45(3) C(2)-C(3) 1.32(4) C(2)-F(2) 1.39(3) C(3)-C(4) 1.36(4) C(4)-C(5) 1.45(4) C(5)-C(6) 1.40(3) C(7)-C(8) 1.36(4) C(8)-C(9) 1.38(4) C(9)-C(10) 1.34(4) C(11)-0(11) 1.18(3) C(21)-0(21) 1.20(3) C(12)-0(12) 1.18(3) C(22)-0(22) . 1.17(3) C(32)-0(32) 1.17(3) C(13)-0(13) 1.11(3) C(23)-0(23)

0 1.16(3)

C(33)-0(33) 1.17(3) Os(4)-C(24) 1.83(3) 0s(4)-C(14) 1.92(3) Os(4)-C(6 1 ) 2.12(3) Os(4)-C(8') 2.18(3) Os(4)-C(9') 2.27(3) Os(4)-C(7 1 ) 2.31(4) Os(4)-Os(6) 2.805(2) Os(4)-Os(5) 3.062(2) 0s(5)-C(25) 1.82(3) Os(5)-C(15) 1.86(3) 0s(5)-C(35) 1.96(4) Oa(5)-C(1') 2.11(3) Os(5)-0s(6) 2.743(2) Os(6)-C(26) . 1.84(3) Os(6)-C(36) 1.84(3) 08(6)-C(16) 1.89(4) 08(6)-C(6') 0 2.23(3) 0.(6)-C(1') 2.33(2) C(1')-C(6') 1.39(4) C(1')-C(2 1 ) 1.43(4) C(2')-C(.3') 1.37(4) C(3')-C(4') 1.37(4) C(4')-C(5 1 ) 1.34(3) C(5')-C(6') 1.48(3)

C(7')-C(8') 1.35(5) C(8')-C(9') 1.38(4) C(9')-C(10') 1.43(4) C(14)-0(14) 1.14(3) C(24)-0(24) 1.20(3) C(15)-0(15) 1.18(3) C(25)-0(25) 1.21(3) C(35)-0(35) 1.12(4) C(16)-0(16) 1.17(3) C(26)-0(26) 1.22(3) C(36)-0(36) 1.17(3)

C(21)-Os(1)-C(11) C(21)-Os(1)-C(6) C(11)-08(1)-C(6) C(21)-Os( 1)-C(S) C(11)-05(1)-C(8) C (6) -Os (1)-C(S) C(21)-Os(1)-C(7) C(11)-Os(1)-C(7) C(6)-Os(1)-C(7) C(8)-Os(1)-C(7) C(21)-Os(1)-C(9) C(11)-08(1)-C(9) C(6)-02(1)-C(9) C(8)-08(1)-C(9) C(7)-Os(1)-C(9) C(21) -Os ( 1)-Os (3) C(11)-Os(1)-Os(3) C(6)-Os(1)-Os(3) C(8)-09(1)-Os(3) C(7)-Os(1)-Os(3) C (9)-Os (1)-OS (3)

-Os ( 1)-Os (2 ) C(11)-Os(1)-Os(2) C (6) -Os (1)-Os (2) C(S) -Os (1) -Os (2) C(7)-08(1)-08(2) C(9)-Os(1)-Os(2) Os(3)-Os(1)-Os(2) C(12)-Os(2)-C(22) C(12)-Os(2)-C(32) C(22)-Os(2)-C(32) C(12)-Os(2)-C(1) C(22)-08(2)-C(1) C(32)-Os(2)-C(1) C(12)-Os(2)-Os(3)

-Os (2)-Os (3) C(32) -Oi (2)-Os (3) C (1)-Os (2) -Os (3) C (12)-Os (2)-Os (1) C (22)-Os (2)-Os (1) C(32) -Os (2)-Os ( 1) C(1)-Os(2)-Os(1) Os(3)-Os(2)-Os(1) C(33)-O5(3)-C(23) C(33)-Os(3)-C(13) C(23)-Os(3)-C(13) C(33)-Os(3)-C(6) C (23)-Os (3)-C (6) C (13)-Os (3)-C (6) C (33)-Os (3)-C (1) C (23)-Os (3)-C (1) C(13)-Os(3)-C(1)

91.2 (11) 90.0(11)

127.1(11) 87.5(14)

117.0(13) 115 .9 (13) 99.3(11) 83.2(11)

148.3(11) 35.6(12) 97.3(11)

149.6(12) 82.1(11) 35.2(11) 66.8(11) 97.5(8) 76.1(8) 51.4(7)

166.1(10) 153 .5 (9) 130.9(9) 151.6(8) 89.9(9) 67.0(7)

117.0(11) 109.1(7) 95.9(9) 55 .43 (4) 96.2(11) 93.3(12) 99.4(12) 94.5(12) 97.5(11)

160.1(10) 93.5(9)

153 .0 (9) 105 .1(8) 56.2(6)

150 .7 (9) 107.7(7) 99.1(8) 66.1(7) 57.63(4) 92.0(12) 90.2(14)

100.7(11) 113.8(12) 92.4(10)

152.3(11) 92.6(11)

123.5(10) 135.6(10)

C(6)-0s(3)-C(1) C(33)-Os(3)-Os(2) C(23)-Os(3)-Os(2) C(13)-Os(3)-Os(2) C(6) -Os (3)-OS (2) C(1)-Os(3)-Os(2) C(33)-Os(3)-Os(1) C(23)-09(3)-'Os(l) C(13)-Os(3)-Os(1) C(6)-Os(3)-Os(1) C(1)-Os(3)-Os(1) Os(2)-Os(3)-Os(1) C(6)-C(1)-C(2) C (6)-C (1) -Os (2) c (2)-c (1) -Os (2) C(6)-C(1)-Os(3) C(2)-C(1)-'0s(3) Os(2)-C(1)-Os(3) C(3)-C(2)-F(2) C(3)-C(2)-C(l) F(2)-C(2)-C(l) C(2)-C(3)-C(4) C(3)-C(4)-C(S) C(6)-C(5)-C(4) C(5)-C(6)-C(l) C(5)-C(6)-Os(l) C(1)-C(6)-Os(1) C(5)-C(6)-Os(3) C(1)-C(6)-Os(3) Os(1)-C(6)-Os(3) C(8)-C(7)-Os(1) C(7)-C(8)-C(9) C(7)-C(8)-Os(1) C(9)-C(8)-Os(1) C(10)-C(9)-C(8) C(10)-'C(9)-Os(1) C(8)-C(9)-08(1) 0(11)-C(11)-Os(1) 0(21)-C(21)-Os(1) 0(12)-C(12)-Os(2) 0(22)-C(22)-09(2) 0(32)-C(32)-Os(2) 0(13)-C(13)-Os(3) 0(23)-C(23)-Os(3) 0(33)-C(33)-Os(3) C(24)-Os(4)-C(14) C(24)-Os(4)-C(6 1 )

C(14)-Os(4)-C(6 1 )

C(24)-Os(4)-C(8 1 )

C(14)-Os(4)-C(8') C(6' )-Os(4)-C(8') C(24)-Os(4)-C(9 1 )

C(14)-Os(4)-C(9 1 )

C(6')-Os(4)-C(9 1 )

C(8' )-Os(4)-C(9') C(24)-0S(4)-C(7') C(14)-0s(4)-C(7 1 )

C(6')-Os(4)-C(7 1 )

C(8')-Os(4)-C(7 1 )

C(9')-09(4)-C(7 1 )

C(24)-Os(4)-Os(6) C(14)-0i(4)-Os(6) C(6')-Os(4)-Os(6) C(8')-09(4)-Os(6)

36.0(8) 102.8(10) 162. 1(7) 89.4(8) 72.6(6) 46.9(6)

160.6(g) 95.9(7)

105.6(9) 48.3(7) 68.3(6) 66.93(4)

112(2) 116.5(19) 131(2) 67.8(14)

120.6(16) 76.9(7)

118(3) 126(3) 115(3) 122(3) 117(3) 121(3) 122(3) 127(2) 109.0(19) 124.0(17) 76.2(14) 80.3(11) 70(2)

134(4) 74(2) 77.6(19)

135(4) 129(2) 67.2(18)

174(2) 174(2) 179(3) 176(3) 179(3) 177(3) 174(2) 174(3) 90.1(13) 91.3(11)

125.0(12) 87.7(14)

115.7(16) 119.3(14) 98.6(10)

149.2(14) 84.5(12) 36.2(11)

101.4(14) 83.5(16)

149.0(14) 34.9(12) 65.8(13) 96.1(8) 73.6(10) 51.6(7)

170.1(11)

C(9' )-Os(4)-Os(6)

C(7' )-Os(4)-Os(6)

C(24)-09(4)-Os(5)

C(14)-Os(4)-Os(5)

C(6' ) -On (4) -On (5) C(8' )-Os(4)-Os(5) C(9' )-Os(4)-Os(5) C(7' )-Os(4)-Os(5) Os(6)-Os(4)-Os(5) C(25)-Os(5)-C(15) C(25)-O&(5)-C(35) C(15)-OS(5)-C(35) C(25)-Os(5)-C(1 1 )

C(15)-08(5)-C(1 1 )

C(35)-Os(5)-C(1 1 )

C(25)-Os(5)-Os(6) C(15)-0.(5)-Os(6) C(35)-Os(5)-O.(6) C(1' )-Os(5)-Os(6) C(25)-Os(5)-Os(4) C(15)-Os(5)-Os(4) C(35)-Os(5)-0s(4) C(1' )-Os(5)-Os(4) 09(6)-Os(5)-Os(4) C(26)-Os(6)-C(36) C(26)-Os(6)-C(16) C(36)-0B(6)-C(16) C(26)-0s(6)-C(6 1 )

C(36)-Os(6)-C(6 1 )

C(16)-08(6)-C(6 1 )

C(26)-O.(6)-C(1') C(36)-Os(6)-C(1 1 )

C(16)-Os(6)-C(1 1 )

C(6')-Os(6)-C(1') C(26) -05 (6 )-Os (5) C (36)-Os (6)-Os (5) C(16)-08(6)-Os(5) C(6' )-Os(6)-Os(5) C(1' )-Os(6)-Os(5) C(26)-Os(6)-Os(4) C(36) -Os (6 )-Os (4) C(16)-Os(6)-Os(4) C(6' )-Os(6)-Os(4) C(1' )-Os(6)-Os(4)

Os(5)-Os(6)-Os(4)

C(6' )-C(1' )-C(2')

C(6' )-C(1' )-Os(5) C(2' )-C(1' )-Os(5) C (6' ) -C(1' ) -Oi (6) C (2' ) -C (1' ) -Oi (6) Os(5)-C(1' )-Os(6) C(3' )-C(2' )-C(1')

C(2' )-C(3' )-C(4')

C(5' )-C(4')-C(3') C(4' )-C(5' )-C(6')

C(1' )-C(6' )-C(5')

C(1' )-C(6' )-Os(4) C(5' )-C(6' )-Os(4) C(1' )-C(6' )-Os(6) C(5' )-C(6' )-Os(6) Os(4)-C(6' )-Os(6) C(8' )-C(7 ' )-Os(4) C(7')-C(8')-C(9') C(7' )-C(8' )-Os(4)

133.9(9)

151.1(11)

150.8(8)

88.0(9)

66.4(8) 119.1(11)

97.8(8) 107.3(11) 55.54(4) 95.8(13)

100.4(14) 94.1(14) 98.2(13) 93.9(13)

158.9(12) 153.0(10) 92.8(9)

104.6(9) 55.6(7)

109.2(10) 149.9(9) 97.6(9) 66.7(8) 57.46(4) 93.2(12)

100.8(12) 90.5(13) 92.6(12)

111.2(11) 153.9(11) 122.0(12) 88.8(11)

137.2(10) 35.3(9)

161.4(9) 101.7(9) 90.2(8) 71.8(7)

48.3(7)

95.2(8) 158.0(8)

107.9(9)

48.1(7)

69.5(7)

67.00(4)

119(3)

113(2)

128(2)

68.4(15)

122.5(19)

76.1(9)

121(4)

123(3)

116(3)

125(3)

115(3)

113(2)

130(2)

76.2(16)

122.9(17)

80.2(10)

67(2)

131(4)

78(3)

)-C(8' )-Os(4)

75.3(18) C(8')-C(9')-C(10')

129(4) C(8' )-C(9' )-Os(4)

68.5(18) )-C(9')-Os(4)

126(2) 0(14)-C(14)-Os(4)

170(3) 0(24)-C(24)-OB(4)

175(2) 0(15)-C(15)-Os(5)

179(3) 0(25)-C(25)-Os(5)

175(3) 0(35)-C(35)-O.(5)

173(3) 0(16)-C(16)-OS(6)

176(3) 0(26)-C(26)-Os(6)

173(3) 0(36)-C(36)-Oa(6)

176(2)

Byunetry transformations used to generate equivalent atoms:

Table 4. Anisotropic displacement parameters (A2 x 10'3) for 1. The anisotropic displacement factor exponent takes the form: -2 pi*2 [ h2 a*2 Ull + ... + 2 h k a* b* U12 ]

Ull U22 U33 U23 U13 U12

05(1) 38(1) 49(1) 46(1) -5(1) 6(1) -5(1) Os(2) 51(1) 45(1) 50(1) -6(1) 12(1) -3(1) Os(3) 41(1) 52(1) 42(1) 0(1) 5(1) -7(1)

50(15) 61(17) 18(11) 13(12) 6(11) -19(13) 54(18) 68(21) 63(20) -21(17) 19(16) -8(16)

F(2) 82(13) 135(18) 66(12) 5(13) -21(10) -4(13) 44(17) 85(23) 66(20) -14(18) 26(15) 14(16) 62(21) 68(22) 116(29) 39(21) 44(21) 29(17)

C(S) 36(15) 70(20) 66(19) 23(16) 9(14) 31(14) C(6) 27(14) 64(19) 94(22) -45(17) 10(14) -21(14) C(7) 66(21) 96(25) 60(20) -18(19) 32(17) -14(19) C(8) 90(29) 163(42) 77(27) 33(28) -6(22) -73(28) C(9) 51(19) 93(26) 82(24) 13(21) 22(18) -29(18) C(10) 68(26) 175(46) 225(54) 132(43) 43(31) 7(28) C(11) 32(15) 69(21) 81(22) -7(17) 8(15) -21(14) 0(11) 94(17) 112(20) 74(16) 38(14) -27(13) -65(15) C(21) 40(15) 39(15) 71(19) 14(14) 23(14) -2(12) 0(21) 74(15) 72(15) 104(18) -18(14) 24(13) -12(12) C(12) 62(20) 64(20) 68(21) 10(17) 11(16) -36(17) 0(12) 109(18) 64(15) 75(15) -12(12) 20(13) -31(13) C(22) 90(23) 36(15) 53(18) -31(14) -3(16) -30(15) 0(22) 88(15) 103(18) 57(13) 3(12) 31(12) -22(14) C(32) 48(18) 43(17) 81(22) 1(16) 8(16) -18(14) 0(32) 77(17) 63(16) 170(27) 12(16) 10(17) 18(13) C(13) 63(20) 87(24) 59(20) 6(18) 29(17) -19(18) 0(13) 143(22) 69(16) 64(15) 21(12) 11(14) -15(15) C(23) 32(15) 55(17) 53(17) 11(14) -7(12) -17(13) 0(23) 69(14) 124(20) 62(14) -17(14) 12(11) 0(14) C(33) 138(32) 74(22) 20(14) -22(15) 3(17) -34(22) 0(33) 77(16) 128(21) 58(14) -13(14) 20(12) -26(15) Os(4) 61(1) 49(1) 46(1) 4(1) 9(1) 9(1) Os(5) 64(1) 48(1) 61(1) 3(1) 26(1) 7(1) 09(6) 45(1) 49(1) 48(1) 5(1) 13(1) 4(1)

62(19) 50(17) 57(18) 11(15) 20(16) -9(15) 101(29) 94(27) 55(20) -15(20) 7(20) -68(24)

F(2'). 38(18) 81(26) 109(29) -16(22) 20(19) 2(18) 52(19) 85(23) 61(20) 4(18) 13(15) 1(18) 57(19) 95(25) 47(18) 7(17) -7(15) -5(19) 75(21) 25(13) 41(15) 2(12) -2(14) -13(14)

P(5') 106(37) 144(46) 195(53) 5(41) -56(36) -23(35) 77(21) 58(19) 40(16) 0(14) 3(15) 2(16) 164(46) 104(35) 121(38) 7(29) 52(34) -5(33) 100(33) 118(36) 75(27) 60(25) -1(23) 11(27) 93(26) 54(19) 53(19) 5(15) 25(18) -7(18)

C(10 1 ) 102(30) 135(37) 110(31) -9(28) 45(25) -37(28) C(14) 43(18) 78(24) 122(31) 29(22) -19(19) 0(18) 0(14) 77(16) 122(22) 92(18) 11(16) -5(14) -23(16) C(24) 25(14) 35(15) 96(22) 24(15) 15(14) 9(12) 0(24) 57(12) 55(12) 92(16) 13(11) -1(11) 29(11) C(15) 55(20) 66(21) 115(28) 27(20) 50(20) 23(17) 0(15) 90(20) 100(21) 179(29) 18(19) 47(19) 41(16) C(25) 86(24) 79(24) 106(28) -17(20) 56(22) 30(19) 0(25) 78(15) 104(18) 76(15) 10(13) 26(13) -2(14) C(35) 120(32) 38(18) 82(25) 15(17) 46(24) 29(19)

0(35) 82(17) 59(15) 99(18) 1(13) 28(14) -20(12) C(16) 105(27) 47(18) 69(21) -9(16) 42(19) 41(19) 0(16) 73(15) 55(14) 129(21) 15(14) 19(14) -16(12) C(26) 75(21) 105(25) 27(15) 16(16) 17(14) 4(19) 0(26) 92(16) 107(18) 54(13) -9(12) 24(12) 25(14) C(36) 55(18) 52(18) 80(22) 40(16) 16(16) 14(15) 0(36) 67(14) 95(16) 75(15) 43(13) 22(12) 25(13)

Table 5. Hydrogen coordinates ( x 10*4) and isotropic displacement parameters (A*2 x 10*3) for 1.

x y X. U(eq)

H(18) 6403(1) 10106(1) 7225(1) 43(60) 9529(17) 9160(17) 9979(19) 75 9575(20) 8241(17) 8957(23) 94 8651(16) 8372(15) 7493(19) 69

H(7A) 5087(19) 9587(18) 6263(20) 86 E(78) 5360(19) 9158(18) 5416(20) 86

5755(25) 8253(25) 6325(25) 136 5973(20) 8964(19) 7830(23) 89

H(1OA) 6950(24) 8315(23) 8590(31) 231 H(1OB) 7153(24) 7890(23) 7752(31) 231 B(IOC) 6227(24) 7768(23) 8067(31) 231 H(2B) 7097(1) 7698(1) - 1111(1) 165(142)

9567(26) 7604(20) 3371(20) 101 9891(20) 8607(18) 4248(19) 79 8806(20) 9466(18) 4378(19) 83 7477(21) 9411(13) 3386(17) 58

H(7'1) 6096(33) 8197(23) -196(28) 152 H(7'2) 5182(33) 8523(23) 92(28) 152

5976(28) 9490(24) 583(24) 120 7588(24) 8869(16) 668(19) 78

H(1OD) 8306(24) 9629(21) 1661(24) 169 H(10E) 7405(24) 9928(21) 1908(24) 169 H(10F) 7657(24) 10134(21) 982(24) 169

i hereby declare that the work contained in this thesis

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