structure and bonding in copper(i) carbonyl and cyanide
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Structure and Bonding in Copper(I) Carbonyl and Cyanide Structure and Bonding in Copper(I) Carbonyl and Cyanide
Complexes Complexes
Robert D. Pike College of William and Mary, [email protected]
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Recommended Citation Recommended Citation Pike, R. D., Structure and Bonding in Copper(I) Carbonyl and Cyanide Complexes (2012). Organometallics.31 (22), 7647–7660. 10.1021/om3004459
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Structure and Bonding in Copper(I) Carbonyl and
Cyanide Complexes
Robert D. Pike*
Department of Chemistry, College of William and Mary, Williamsburg, VA 23187-8795.
RECEIVED DATE (to be automatically inserted after your manuscript is accepted if required
according to the journal that you are submitting your paper to)
ABSTRACT The coordination chemistry of copper(I) carbonyls and cyano complexes is reviewed.
Primary attention is focused structural chemistry, including coordination behavior, bridging modes,
network formation, flexible coordination number, and reversible ligand binding. Additional coverage of
infrared spectroscopy and orbital interactions in carbonyl and cyanide bonding, and photophysical
behavior of metal cyano complexes is also included.
BRIEF The coordination chemistry of copper(I) carbonyls and cyanide complexes is reviewed.
Introduction
The isoelectronic diatomics carbon monoxide and cyanide have rich histories as ligands for transition
metals. Both ligands inevitably bond metal centers primarily through carbon, placing them amongst the
simplest and most robust of carbon-bound ligands. However, despite the clear analogy between CO and
CN−, carbonyl is regarded as one of the quintessential ligands in organometallic chemistry, whereas
cyanide has traditionally been regarded a strictly inorganic ligand. There are some good arguments for
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this designation, such as the analogy between CN− and the halides, its stability as an aqueous anion, and
its ability to form simple metal salts. Nevertheless, there are arguably better reasons for classifying
metal-cyano complexes as organometallics. Foremost among these is the aforementioned M−CN
linkage, but of equal importance is the bonding analogy of CN− with CO, as well as with the
isoelectronic N2 and NO+. Bonding in each of these ligands involves a combination of -donation by the
HOMO (or NHOMO, in the case of N2), and -acceptance (-backbonding) by the LUMO (see Fig. 1).
The latter is, of course, instrumental in stabilizing the electron-rich d-subshell that is hallmark of low-
valent transition metal organometallics. Because cyanide -donation is relatively strong and its -
acceptance relatively weak, CN− can often support higher oxidation states that can the carbonyl ligand.
Nevertheless, the fact that copper(I) cyanide is air-stable, and copper(II) cyanide does not normally exist
is a tribute to the reducing power of cyanide, either through electron sharing or out-and-out electron
transfer.
Figure 1. Bonding in metal-carbonyl and metal-cyano complexes.
Both carbonyl and cyanide are notable for their ability to act as either terminal or bridging ligands.
Unlike the dianionic peroxo ligand, neither CO nor CN− is known to chelate. As suggested in Fig. 2, all
terminal carbonyls and cyanides are C-bound. Bonding distinctions between CO and CN− become
apparent in their bridging behavior. When the carbonyl ligand bridges metal centers, it shares its largely
carbon-centered HOMO electrons with two, or even three, metal centers (2-C,C or 3-C,C,C mode),
Figs. 1 and 2. The bridging carbonyls are shown as triply bonded in Fig. 2 to avoid any implication that
carbonyl is reduced to a dianion (i.e., deprotonated formaldehyde, O=C2−) during bridging. It remains
neutral C≡O, simply sharing the lone pair with two or three metal atoms. Bridging cyano ligands are
very common. In contrast to the 2-C,C behavior of bridging CO, secondary ligand connections for
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cyanide involve N-bonding (2-C,N mode, Fig. 2). In those cases for which cyanide links to three metal
centers, the 3-C,C,N mode is invariably found. This latter mode is usually part of a dimeric
arrangement that features a relatively close metal-metal interaction, as shown using a dashed line in Fig.
2.
Figure 2. Bridging modes in metal-carbonyl and metal-cyano complexes.
The history of metal carbonyls, starting with Mond’s Ni(CO)4, is closely intertwined with the history
of organometallics itself. This saga has been often told and does not need repeating here. However, it
should be pointed out that structurally characterized copper carbonyls are relatively late additions to the
catalog of metal carbonyls. While the study of Cu−CO complexes has only bloomed in the last several
decades,1 cyanide complexes have a long history in inorganic chemistry.2 One of standouts in this story
is the mixed valence iron cyanide called Prussian Blue, {Fe4[Fe(CN)6]3}. Although originally used as a
substitute pigment for expensive Lapis lazuli, cyanide-bridged cage structures related to Prussian Blue
that feature redox active metal centers have recently been an active area of research in
magnetochemistry, catalysis, and electron transfer studies. This work is summed up in some recent
reviews.3 The current review will focus on the coordination chemistry of copper(I) carbonyl and cyanide
complexes, paying special attention to the structural and network chemistry. Spectroscopic and
photophysical behavior will also be touched upon. Copper(II) carbonyls are not known, and copper(II)
cyano complexes, except for some mixed valence cyanocuprates, will not be covered.
Copper(I) Carbonyls
4
The reactivity of CuCl with CO has been recognized since the 19th century. Solutions of CuCl readily
absorb carbon monoxide at CO pressures of under 1 atm.4 The adduct that is formed, CuCl(CO), has a
sheet-like structure. It features a C≡O of 2127 cm−1, indicative of surprisingly little -backbonding.
CuCl(CO) releases CO at pressures of under 0.5 atm CO. The carbonylation of MCuCl4 (M = Al, Ga)
results in MCuCl4(CO) phases, I.5 Due to the highly electron-deficient nature of the Cu(I) environment
in I, these materials exhibit enhanced -donor behavior with essentially no -backbonding, as indicated
by the C≡O of 2156 cm−1, which is actually higher than the free CO value of 2143 cm−1 (see Table 1).
This unusual form of MCO bonding has been described as non-classical. Titration of sub-atmospheric
pressures of CO into solid Cu(AsF6) has led to the formation of the homoleptic, non-classical cations
Cu(CO)n+ (n = 1, 2, and 3).6 The unusual 3-coordinate copper dicarbonyl, II, also shows very high
frequency carbonyl stretching bands at 2158 and 2184 cm−1.7 The 18-electron Cu(CO)4+ ion has been
crystallographically characterized as part of a salt with a carborane anion (C≡O = 2184 cm−1).8 The same
paper reports the Cu(CO)2 fragment coordinated to an alkene bearing a pendant carborane anion. Neon-
matrix-isolated CuCO+ shows the highest recorded stretching frequency of 2234 cm−1.9
Table 1. Some representative Cu(I)-carbonyl stretching frequencies
Material/Complex C≡O, cm−1 a Reference
[Cu(CO)]+, Ne/CO matrix 2234 9
Cu[N(SO2CF3)2](CO)2, II 2184, 2158 7
[Cu(CO)]+(AsF6)− 2178 5
CuAlCl4(CO), I 2156 4
Cu(O2CCF3)(CO), IV 2155 14d
5
CO 2134 (g) −
[(2,9-tBu2Phen)Cu(CO)]+(SbF6)−, VI 2130 (CH2Cl2) 17k
CuCl(CO) 2127 4c
{[(2-PyCH2)3N]Cu(CO)}+[B(C6F5)4]−, VIII 2091b, 2074c (THF) 17i
[(bpen)Cu(CO)(CH3CN)+(PF6)−]∞, VII 2088 19a
[(Pipz)CuCl(CO)], IX 2084 30
TpCu(CO) 2083 24a
(en)CuCl(CO) 2080 28a
{[(en)Cu(CO)]2(2-en)}2+(BPh4−)2 2078 17b
{CpCo[(MeO)2PO]3}Cu(CO), V 2075 (hexane) 16
CuCl(CO), MeOH solution 2070 4b
[(2-Py)2NH]CuCl(CO) 2069 28e
[(tBuO)Cu(CO)]4, III 2063 (toluene) 11
[(en)2Cu(CO)]+I− 2060 17b
[(2-MeQuinO)Cu(CO)]4d 2050 10a
[Cu2(-CO)(-isonicotinoate)2], X 1950 32
{[(tmen)Cu]2(-O2CPh)(-CO)}+(BPh4)− 1926 31a
{Cu3[(2-CO)2(3-CO)MoCp]3}, XI 1969, 1899, 1863, 1820 33
aAll values recorded in solid state, KBr, or Nujol mull, except as noted. b4-Coordinate Cu with
pendant pyridyl arm. c5-Coordinate Cu. d2-MeQuinO = 2-methylquinolin-8-olato.
Uncharacteristically for the soft copper(I) ion, the CuCO unit is often found coordinated to the oxygen
donor anions: alkoxide,10-13 carboxylate,14 sulfonate,15 and phosphonate.16 These complexes, which are
usually formed under 1 atm of CO, form oligomers and polymers, such as III-V.11,16 The cubane
6
geometry reflected in III is very common for Cu(I), most commonly being encountered with 3-halide
corners.
The most common coordination sphere for CuCO complexes involves amine ligands, usually
chelating. A great many such monomers,17 amine-bridged dimers,17a,18 and occasionally higher
oligomers19 are known. A rare structurally-characterized non-chelate is (NH3)3Cu(CO)+, which was
crystallized as a Co(CO)4− salt.20 An interesting CuCO complex of 6-trans,trans,trans-1,5,9-
cyclododecatriene has recently been reported.21 Remarkably, several five coordinate N4Cu−CO
complexes violate the usual rule that Cu(I) does not allow coordination numbers above four.17i,22,23
Studies of Cu(I) carbonyl complexes bearing potentially tetradentate nitrogen ligands have revealed a
four-to-five coordination number equilibrium, with the fourth nitrogen site alternately coordinated and
“dangling”.17i,17m Complexes VI-VIII are examples of 3-, 4-, and 5-coordinate amine CuCO
cations.17i,17k,19a Complex VII is a unique example of a polymeric copper carbonyl cation. Generally,
cationic CuCO complexes have modest stability at best, and are subject to CO dissociation in the
absence of CO atmosphere. Copper(I) fragments that bind carbonyl can usually bind -alkene or
dioxygen in place of CO; substitution of oxygen for CO is more difficult since Cu−CO bonding is
usually stronger than the Cu−O2 bonding.
7
Copper carbonyl stability is generally enhanced by the presence of chelating anionic ligands, including
tris(pyrazolyl)borate (Tp−) and its analogs,24,25 among others.22,26 Some cationic tris(pyrazolyl)methane
(Tpm) complexes of CuCO have also been prepared.25,27 Careful comparison of Tp− and Tpm species by
X-ray, DFT calculations, voltammetry, IR, and reactivity have confirmed expectations that the more
electron-rich TpCuCO complexes exhibit greater stability due to higher degree of -backbonding, as
evidenced by stronger Cu−C and weaker C≡O bonding.25 In fact, the first structurally characterized
copper carbonyl complex, TpCuCO, reported in 1972,24a is still among the most stable known.
Copper carbonyl species with coordinated anions are common. These can take the form of simple
monomers L2Cu(CO)X (X = Cl, I, ClO4, or OTf)18j,28 or anion-bridged dimers L2Cu(CO)(-
X)Cu(CO)L2+ (X = Cl, Br, I, or ClO4).4b,18j,29 Copper(I) tends to form rhomboid dimers via the bridging
of halide ions, Cu(-X)2Cu. These dimers have been strung into linear polymers using bridging
diamines in the presence of CO to form polymers, IX.30 Although copper readily forms bridging
arrangements with other metal carbonyls during cluster formation, only a few clusters containing
homonuclear 2-C,C Cu2(2-CO) complexes are known. These include a few carboxylate scaffold-
supported Cu(I) dimers (see X).31 This scaffolding of Cu2(2-CO) by carboxylate has been used to
produce a pair of interesting 5-coordinate 2-D polymers, [Cu2(2-CO)(nic)2], X (nic = isonicotinoate,
nicotinoate).32 Homonuclear bridging Cu(I) carbonyls are also found in several clusters containing Fe33
and Mo (XI).34 The latter is quite interesting structurally, exhibiting a triangle of Cu atoms sharing
cuprophilic interactions. The Cu…Cu bond distances in such interactions (in this case 2.6211(13),
2.6167(13), and 2.6594(13) Å) are near or less than the van der Waals radius sum (about 2.80 Å), and
therefore represent significant overlap between the Cu 4s or 4pz orbitals. In this case the bond lengths
are shorter even than the 2.65 Å Cu−Cu value in copper metal. Cuprophilic interactions are found
extensively in cyano-bridged complexes. Most such interactions are supported by additional bonds, such
as a bridging carbonyl or cyanide. Unsupported cuprophilic interactions are rare.
8
CuCN
Copper(I) cyanide is an air-stable, nearly white solid that is essentially insoluble in all common
solvents. It does dissolve in aqueous solutions of alkali cyanides, in which case soluble complex anions
Cux(CN)y−(y−x) are formed in equilibrium.35 CuCN has two known polymorphs (Fig. 3). The
commercially available low-temperature phase contains rippled 1-D polymer chains in which 2-
coordinate Cu(I) centers are bridged by site-disordered CN−.36 The undulating chains are produced by
five crystallographically independent Cu atoms with X−Cu−X = 176.7−179.0° and Cu−X−X =
174.0−179.4°. The high temperature polymorph forms above 565 °C. It is crystallographically much
simpler,37,38 having the same structure as AgCN,39 i.e. a single linear 2-coordinate unique Cu atom
coordinated to a site-disordered CN. Significantly, in neither structure is there any evidence of
cuprophilic interactions, cyano bridging, or coordination of copper to a third ligand.
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Figure 3. X-ray structures of low temperature (left) and high temperature (right) forms of CuCN (copper
orange, disordered nitrogen and carbon grey).36-38
Luminescence spectroscopy of copper(I) cyanide reveals a broad, intense absorption feature with
peaks at 288, 307, and 345 nm and an intense emission band at 392 nm.40 This phosphorescence
emission peak shows a slight thermochromic shift to 412 nm at 77 K. Recent work by Bayse using DFT
to study model compounds of the infinite …Cu−C≡N… system suggested that the origin of the excitation
is associated with -symmetry transitions from orbitals that are essentially Cu d/CN to Cu p/CN *.41
This effect is exemplified by the 7g to 7u excitation in K2Cu(CN)2+ (Fig. 4). Although this transition is
alternately referred to as being either MLCT or Cu-centered in nature, in fact it is really a combination
of the two. The resulting triplet state undergoes a Jahn-Teller type symmetry distortion, leading to
removal of the excited state degeneracy (Fig. 4).
10
Figure 4. Walsh diagram of the distortion of the π MOs of the triplet state of K2Cu(CN)2+ in C2V
symmetry, Cu atom located at center and K atoms at the ends.41
The finding accords well with the observation of excimer and halide exciplex formation of Cu(CN)2−*
in aqueous solution.42 Formation of a trigonal exciplex with halide, which is illustrated in reaction (1),
leads to characteristic blue-green luminescence emission a centered at 476, 482, and 486 nm for X =
Cl−, Br−, and I−, respectively, upon excitation around 280 nm.
Cu(CN)2−* + X− → Cu(CN)2X2−* (1)
The lowering of the Cu(CN)2− emission energy upon trigonal deformation is consonant with the results
shown in Fig. 4. The lowering of excited state emission energy via bending at copper explains the
observation that amine substituted CuCN-L polymers (see below) emit at longer wavelengths than does
CuCN, moving well into the visible region.40,43Addition of ammonia to Cu(CN)2− has been shown to
produce Cu(CN)2(NH3)−, as well as Cu3(CN)2(NH3)5+ and Cu3(CN)4(NH3)3
−.44 All of the Cu(CN)2−
adducts: Cu(CN)32−, Cu(CN)2X2−, and Cu(CN)2(NH3)−, when photo-excited, can also form long-lived
excited states that photo-eject an electron to the solvent with high quantum efficiency.42e,44
Infrared and Raman Analysis of Copper(I) Cyanides
Cyanide C≡N exhibits a strong band in the IR in the range of 2050−2200 cm−1 (Fig 5A). In pure
CuCN, this band is found at 2170 cm−1.39 In cyano-bridged compounds, such as CuCN itself, a single
Cu−C/N band is invariably observed, representing the average energy of the Cu−C and Cu−N bonds.
The C≡N stretching frequency in CuCN complexes correlates well with the crystallographically
determined Cu−C/N distance.45-47 A decrease of about 35 cm−1 in C≡N corresponds to an elongation of
about 0.1 Å. Solid state spectra of CuCN should not be collected as KBr pellets due to a reversible
reaction between CuCN and Br− in the solid state. Like CO ligands, CN groups might be expected to
show IR frequencies corresponding to weaker stretching when bridging. However, IR indicates that -
C,N bridging C≡N is usually slightly stronger. This effect appears to be the outcome of the relatively
strong CN bonding.39,48 In bridged cyanides, C≡N decreases as the Cu coordination number increases.
11
Again, these data correlate to Cu−C/N bond lengths: 1.80 to 1.86 Å in the nearly linear 2-coordinate
systems, 1.92-1.96 Å in the planar 3-coordinate complexes, and 1.94-2.00 Å for 4-coordinate
cyanocuprates. In the far IR (and Raman), bands have been identified for the other normal vibrational
modes of pure CuCN (Fig. 5): B = 591 cm−1, C = 326 cm−1, and D = 168 cm−1.39 These values are nicely
supported by DFT results.41b Upon addition of ligands to the copper(I) centers in the CuCN chain, bands
A−C show a decrease in frequency. Band D becomes non-degenerate, splitting into a higher and lower
frequency pair of features.47
Figure 5. Normal vibrational modes in CuCN.39
Non-networked CuCN Complexes
Copper(I) complexes containing cyano ligands that do not bridge are relatively few in number. They
can be divided into four main subgroups: (1) L3CuCN,43,49 (2) L2Cu(CN)2−,50 (3) simple cyanocuprates
Cu(CN)2−, Cu(CN)3
2− and Cu(CN)43−,42,51-53 and various metal clusters incorporating CuCN.54 Examples
of the former groups include [(LL)Cu(PPh3)(CN)], [(LL)Cu(CN)2]− (LL = 2,2'-Bpy, Phen, and related
ligands). Only one compound of this type is constructed solely from monodentate ligands: (1-
MeIm)3CuCN.43 Species XII and XIII are unique examples of neutral 3- and 2-coordinate CuCN
complexes.51b,55 In XII the trigonal angle sum is a nearly planar value of 359.5°, and in XIII the
C−Cu−C bond angle is a nearly linear 177.5(3)°. Given the tendency of cyanide to bridge copper(I)
centers, these coordinatively unsaturated cyano complexes are remarkable for not completing the Cu
12
coordination sphere in this way. Species XIV exhibits a cuprophilic interaction supported by the
bridging diphosphine with a Cu…Cu distance of 2.940(1) Å.56 The Mo-Cu cation XV is another example
of a Cu(I) cubane.53k Several instances of simple cyano-bridged mixed valence Cu(I)-Cu(II) complexes
with terminal cyanides are known.57 An example is XVI, which is essentially a collapsed ion pair
between CuI(CN)32− and CuII(1,3-propanediamine)2
2+.57d In all such mixed valence complexes, cyanide
C always bonds to Cu(I) and N to Cu(II). Finally, there are a handful of known complexes which feature
a simple CuI−C≡N−CuI bridge.47b,50b,50c,58 These generally involve large and/or chelating ligands. One
example is XVII.58b
Cyanocuprate networks
It has been noted that monomeric cyanocuprates of formulas Cu(CN)2−, Cu(CN)3
2−, and Cu(CN)43−
exist in aqueous solution and in certain solid state structures. Cyanocuprates more commonly occur as
anionic networks (Fig. 6). Like simple cyanocuprate monomers, many of these anionic networks are
highly photoluminescent. In the vast majority of cyanocuprate networks, cyanide atom positions are
disordered. The simplest of these is a polymeric version of Cu(CN)2− (XVIII), which is encountered as
its K+, [Na(H2O)2]+, or nBu4N+ salt.51a,59 In this polymer, zigzag (CuCN) chains are decorated with a
terminal ordered cyano at each roughly planar Cu atom. The cation is associated with the nitrogen atom
of the pendant cyanide, bridging the chains. In the related mixed anion cyanocuprates Cu(CN)X−, (X =
Br, I), the basic chain structure is retained, with the halide ions replacing the pendant CN groups.45 The
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commonly-encountered cyanocuprate Cu2(CN)3− allows all copper atoms to be 3-coordinate. This
usually leads to a (6,3) hexagonally tiled sheet consisting of (CuCN)6 rings, XIX. In addition to two
polymorphs of KCu2(CN)3,60 Cu2(CN)3− salts of other alkali metals, ammonium, tetraalkylammonium,
PPh4+, and other cations,61 or copper(II) complex ions (see below) have been reported. As is the case
with all networked cyanocuprates, the cations tend to be found inside the large network pores. In one
case, a mixture of (CuCN)6 and (CuCN)5 rings was observed.62 Most of these 2-D Cu2(CN)3− sheets are
flat, however, increased rippling is seen with larger cations.
Figure 6. Some cyanocuprate network structures.
Three-dimensional cyanocuprate networks can arise either through 3-C,C,N cyano bridging or 4-
coordinate Cu centers. The former is rare, but has been encountered.63 The resulting 3-D framework
anionic materials contain organic cations which act as templating agents within the pores. The
Cu2(CN)42− network, XX, contains 4-coordinate Cu and forms a diamond-like network (Fig. 6).64,65 The
Cu3(CN)4− ion (XXI) in the nBu4N+ salt shows a tiled hexagonal pattern similar to that of Cu2(CN)3
−,
but with the replacement of a two CN units in each (CuCN)6 ring by −CN−Cu−CN−, expanding the
rings in one trigonal direction (Fig. 6).45 These same 2-coordinate copper units, −CN−Cu−CN−, are
found along all six edges of the giant 36-atom macrocycle (CuCN)12 that occurs in the Cu(I)-Cu(I) salt
[Cu2(CN)(Bpy)2]+[Cu5(CN)6]−,66 and the mixed valence Cu(I)-Cu(II) compound Cu5(CN)6(DMF)4.67
14
Several unusual variations on the known cyanocuprate network themes have appeared. Hydrothermal
reactions are notorious for producing unexpected products. Hydrothermal treatment of a mixture of
CuCl2, tetrazole, and MeCN at 160 °C produced a solution which yielded two polymorphs of
[H5O2]+[Cu2(CN)3]−.68 The source of the cyanide ion presumably was the acetonitrile solvent. Although
both of these networks show the standard (6,3) Cu2(CN)3− network, one of them exhibits a 2.86 Å
cuprophilic interaction between adjacent layers link the rippled sheets into a diamondoid network. The
hydrogen-bonded, protonated water dimers sit within anion lattice pores. In the other polymorph,
Cu…Cu interactions are much more tenuous (>3 Å) and the (6,3) honeycomb is more like that seen for
other Cu2(CN)3− lattices. The Cu9(CN)15
6− ion found in a benzylviologen salt has nine
crystallographically independent Cu centers, three of which are 4-coordinate.69 In this anion (CuCN)8
and (CuCN)3 helices are linked together.
Chippindale and Hibble have reported several interesting cyanocuprates using K+ and Cs+ counterions
produced under hydrothermal conditions.60b The complex K2[Cu3(CN)5] forms an unusual planar sheet
of (CuCN)8 rings. One of the 2.5 independent cyano groups is terminal (C-bound) and points into the
tiled ring (Fig 7A). A very different sort of [Cu3(CN)5]2− network is found in the mixed valence complex
Cu4(CN)5(NH3)4(H2O)2 (Fig. 7D).70 In this case, 3-C,C,N dimers bridge (CuCN)4 rings into a 3-D
network. A very short cuprophilic interaction (Cu1…Cu2 = 2.4885(7) Å) is present within the dimers.
The cyanocuprate networks, Cu3(CN)4−, found for alkali salts differ greatly from that of XXI. In
Cs[Cu3(CN)4], (CuCN)8 rings form buckled sheets that enable two identical networks to interpenetrate
(Fig. 7B). The K+ salt of Cu3(CN)4− is more complex, containing 2-, 3-, and 4-coordinate Cu(I) centers
in a quadruply-interpenetrated 3-D net (Fig. 7C) that is analogous to that of Ag2Cu(CN)4−.71
15
Figure 7. (A) (6,3) (CuCN)8 sheet in K2Cu3(CN)5.59b (B) Interpenetrating (6,3) (CuCN)8 sheets in
CsCu3(CN)4.60b (C) top: (4,4) Anion net in KCu3(CN)4. Bottom: Interpenetration of four nets.60b (D)
[Cu3(CN)5]2− Anion net in Cu4(CN)5(NH3)4(H2O)2.70 (E) Anion net in [Me4N]2[Cu4(CN)5Cl].73 (F)
Interpenetrating sub-lattices (color and greyscale) in Cs[Cu3(CN)3Br] (Br green spheres).72
The use of solventothermal conditions has led to the formation of interesting halo-cyano networks,
including K[Cu2(CN)2Br]•H2O, K3[Cu6(CN)6I3]•2H2O, Cs[Cu3(CN)3X] (X = Cl, Br, Fig. 7F),
Cs2[Cu4(CN)4I2]•H2O,72 and [Me4N][Cu3(CN)2Br2] and [Me4N]2[Cu4(CN)5Cl] (Fig. 7E).73 All of the
alkali-containing 3-D networks contain infinite CuCN chains with various forms of halide cross-linking.
In the case of [Cu4(CN)5Cl]2− the 3-D network is produced via cross-linking of the CuCN/CuCl chains
by 3-C,C,N cyano dimers. In contrast, the [Cu3(CN)2Br2]− anion is composed of a fused ring (CuBr)2
ladder motif that is cross-linked by NC−Cu−CN units.
Thus far, we have focused almost exclusively on cyanocuprate(I) networks, but mixed valence
cyanocuprates are also widely recognized. There are two general types: those in which isolated
16
copper(II) ions are guests within a cyanocuprate(I) lattice, and those for which cyanide bridging
produces a single network. The Cu(II) guest molecules that have been identified in cyanocuprate(I) nets
include Cu(H2O)42+,71,73 Cu(NH3)4(H2O)2+,70 Cu(en)2(H2O)2+,64,74 and Cu(NN)2
2+ (NN = en or 1,3-
propanediamine),64,65,75 There exists a wide range of integrated Cu(I)-Cu(II) cyanocuprate networks.
These vary from 1D to 3D, higher dimensionality networks being extended through 3-C,C,N bridging
or the occurrence of 4-coordinate Cu atoms.65,67,75,76 Several examples are shown in Fig. 8. The many
known mixed metal cyanocuprates are considered beyond the scope of this review.
Figure 8. (A) Ribbon of fused Cu5(CN)5(NH3)3 rings in CuIICuI2(CN)4(NH3)3.76e (B) Sheet of tiled
Cu12(CN)12(cyclam)6 with 4-coordinate Cu centers and pendant cyano units in
CuII3CuI
2(CN)8(cyclam)3(H2O)5.76d (C) Rippled sheet of tiled Cu6(CN)6(dmen)3 rings in [CuIICuI
(CN)3(dmen)].65 (D) 3-C,C,N-bridged 3-D structure of CuIICuI4(CN)6(DMF)4.66 In Figures 8, 11, 13-15,
except as noted: copper atoms are shown as orange spheres, cyano nitrogen and carbon (although often
disordered) as blue and grey spheres, respectively, and non-cyano ligands as wireframe; hydrogens are
omitted.
CuCN-L Networks
Copper(I) cyanide itself features unusually low-coordinate metal centers. As a result, it has a strong
tendency to acquire additional ligands. This usually results in simple decoration of the CuCN zigzag
chain, as shown in Fig. 9. A list of polymeric CuCN-monodentate ligand complexes is provided in Table
17
2. Although the most commonly found m/n value for (CuCN)mLn, is 1 (XXIII), both more and less
ligand-rich cases are well established. An m/n ratio of 1 usually means 3-coordinate copper centers,
while values >1 suggest the presence of 2-coordinate centers, and values <1 suggest the addition of 4-
coordinate centers. It is not at all unusual for a particular ligand to give rise to multiple (CuCN)mLn
stoichiometries depending on the availability of L, e.g. (CuCN)7Py4, (CuCN)5Py4, (CuCN)2Py.43 The
many simple zigzag (CuCN)L complexes show large cyano−Cu−cyano angles (130.3−148.9°) indicative
of weak ligand binding.43 A plot of these angles versus Cu−N bond lengths (2.044−2.205 Å) shows a
rough correlation. Both metrics confirm that bonding is weaker for aliphatic than for aromatic amines.
CuCN-L stoichiometry is usually easily determined through thermogravimetry, see Fig. 10, wherein
sequential loss of 2-MePy in traces A and B suggests transformations (1) – (3):77
(CuCN)2(2-MePy)3 (s) → 2 (CuCN)(2-MePy) (s) + 2-MePy (g) ↑ (1)
2 (CuCN)(2-MePy) (s) → (CuCN)2(2-MePy) (s) + 2-MePy (g) ↑ (2)
(CuCN)2(2-MePy) (s) → 2 CuCN (s) + 2-MePy (g) ↑ (3)
Figure 9. Nucleophile-decorated CuCN chain arrangements.
18
Figure 10. Thermogravimetric traces of (A) (CuCN)3(2-MePy)2, (B) (CuCN)(2-MePy), and (C) CuCN
exposed to saturated atmosphere of 2-MePy at room temperature.77
Table 1. (CuCN)m(L)n complexes (L = monodentate ligand).
m/n Lattice Type L Cu
Coord.a
References
3:1 3-C,C,N 2-D sheets
with –CN−Cu−CN−
links, and terminal
Cu(OH2) units
H2O 2, 3 78
2:1 2-C,N 1-D chains 3-MePy, NHiPr2, PPh3 2, 3 43,79
7:4 2-C,N 1-D chains
with threaded CuCN
chains
Py 2, 3 43,80,81
3:2 2-C,N 1-D chains PhCN, o-MeC6H4CN 2, 3 47c
4:3 [no structure] N-EtPipd − 43,77
5:4 [no structure] Py − 43,47a,77
1:1 3-C,C,N 2-D sheets NH3, CH3CN 3 82,47c
1:1 2-C,N 1-D chains DMSO, CNtBu, (CH3CN•0.5 18-
crown-6), EtCN, S=C(NMe2)2,
S=C(NH2)CH3,b 2-MePy, 3-MePy, 2-
EtPy, 3-EtPy, 4-EtPy, 2-ClPy, 3-ClPy,
2-BrPy, 3-BrPy, 2,4-Me2Py, 2,4,6-
Me3Py, 3-AcOPy, 4-AcOPy, 4-EtO2C-
Py, Quin, NHEt2, NEt3, N-MePipd,
Me2NCy, N-MeMorph,b MBIA,c
3 43,47a,47c,5
5,77,80,81,8
3-85
19
DMPzd
1:1 2-C,N cyclic
oligomers
PCy3, TMTHTe 3 56,86
3:4 2-C,N 1-D chains Pipd, PyBImf 3, 4 43,77,85,86
2:3 2-C,N 1-D chains 2-MePy, 3-MePy, 4-MePy, 3-EtPy,
NH2Cy
3, 4 43,47a,77,84,
87
2:3 2-C,N 1-D chains plus
½ molecule of free
ligand
4-tBuPy 3 43,77
1:2 2-C,N 1-D chains Py, (3:1 Py:PPh3), 3-ClPy, 3-MeOPy,
P(OPh)3
4 43,47a,47b,7
7,89,90
1:2 2-C,N cyclic
hexamers
PPh3 4 61b
aC,C-cyanide bridges assigned as ligand to only one Cu. bLong range Cu…S of 2.708(4) Å in
(CuCN)[S=C(NH2)CH3]85b and Cu…O of 2.537(3) Å in (CuCN)(N-MeMorph)43,77 weakly cross-link
CuCN chains. cMBIA = 2-(2-methyl-1H-benzo[d]imidazol-1-yl)acetonitrile. dDMPz = 3,5-dimethyl-1H-
pyrazole eTMTHT = 3,3,6,6-tetramethyl-2,3,6,7-tetrahydrothiepine (2-alkene-bonded). fPyBIm = 2-
(pyridin-4-yl)-1H-benzo[d]imidazole.
Several CuCN chains decorated with small ligands (H2O, NH3, MeCN) are further cross-linked to
form 2-D sheets via 3-C,C,N bridging. The resulting bimetallic nodes typically show cuprophilic
interactions, and usually link according to XXVI. Other, less-commonly encountered, 3-C,C,N
bridging variants include XXVII and XXVIII.91 The aqua compound (CuCN)3(H2O) is a very unusual
species for two reasons: (a) it shows rare cyano−Cu(I)−O bonding, and (b) it features XXVI dimer units
that are bridged in one direction by pendant 2-coordinate –CN−Cu−CN− units and are capped by
−Cu−OH2 units in another direction (Figure 11A).78 Another interesting network is (CuCN)7Py4, which
consists of both (CuCN)Py and CuCN chain sub-lattices. These interact together through remarkably
short, unsupported Cu…Cu interactions of 2.4537(17) Å (Figure 11B).43 2,3-Dihydroxyquinoxaline
forms a self-hydrogen-bonded network that is shot through with CuCN chains, which are only very
20
weakly associated with lattice oxygen atoms (Cu…O = 2.728(5) and 2.697(5) Å, cyano−Cu−cyano =
169.9(2)°), Fig. 11C.92
Figure 11. (A) (CuCN)3(H2O) structure featuring 3-C,C,N bridging units bearing terminal Cu(OH2)
groups.78 (B) (CuCN)7Py4 structure featuring (CuCN)Py and CuCN sublattices.43 (C) Structure of
(CuCN)(2,3-dihydroxyquinoxaline) showing weak coordination of CuCN to H-bonded ligand network
(dashed lines).92 Hydrogens shown.
Our group has shown that reversible adsorption of amine or sulfide nucleophiles by bulk CuCN
produces a shift of photoluminescent emission into the visible range.43,77 This reaction occurs
spontaneously upon exposure of CuCN to liquid or vapor, providing the foundation for possible vapor-
detection systems. The amount of nucleophile taken up by CuCN particles upon vapor exposure is quite
small as revealed by TGA (see Fig. 10, trace C), nevertheless, a remarkable diversity of luminescence
colors is produced, even for very similar amines (Fig. 12). The origin of the red shift appears to be
21
associated with bending at the Cu centers along the chain (see above), and the range of emission
wavelengths appears to be tied to the stoichiometric and structural diversity of the surface product
phases. Alternative stoichiometries for a particular nucleophile tend to produce different emission
colors. For example, (CuCN)(2-MePy) emits at 452 nm (blue) and (CuCN)2(2-MePy)3 emits at both 452
and 525 nm (yellow-green). Both colors are visible in Fig. 12K.
Figure 12. Luminescence of CuCN + liquid L under 254 nm light at room temperature.77 A: Pipd B: N-
MePipd, C: N-Et-Pipd, D: N-MePyrrolidine, E: Me2NCy, F: NEt3, G: N-MeMorph, H: N-MePipz, I:
N,N'-Me2Pipz, J: Py, K: 2-MePy, L: 3-MePy, M: 4-MePy, N: 2-EtPy, O: 3-EtPy, P: 4-EtPy, Q: 4-tBuPy.
Bidentate chelating nitrogen and phosphorus ligands, such as 2,2′-Bpy and Phen, bind to CuCN
chains, forming 4-coordinate Cu centers.84,93 Stoichiometries of fewer than one chelate ligand per
copper contain both 4-coordinate and ligand-free 2-coordinate Cu centers within the chains. In some
cases, −CNCu-L or –CNCuCNCu-L branches pendant to the main CuCN chain bear some or all of the
ligands at their termini.40,66,93e,93m,94 In an unusual variation on the chain decoration theme, a long ligand
(2,5-bis(3-pyridyl)-1,3,4-oxadiazole) bridges pairs of Cu atoms lying along CuCN chains.95
Copper(I) cyanide networks that are cross-linked by bridging ligands are legion. Although they are
generally prepared directly from CuCN, desulfurization of CuSCN by dppe has been reported.96 The
simplest networks utilize 3-coordinate Cu centers, and are formed via simple bidentate ligand cross-
linking of pairs of CuCN chains into 1-D ladders or series of CuCN chains into 2-D sheets. Only a very
few ladders are known;88,91,97 one example uses the phthalazine ligand, Fig. 13A.91 Cross-linked sheets
22
usually feature (6,3) networks with tiled 3-coordinate Cu6 rings.91,93o,96,98,99 Long ligands can form (4,4)
tiled networks with 4-coordinate Cu centers (Fig. 13B),95,100 and larger rings occasionally incorporate 2-
coordinate Cu spacers.88 A few of these sheet networks additionally incorporate independent CuCN
chains as a second sub-lattice threaded through the macrocyclic rings of the sheet structure. The known
examples include [(CuCN)2(Pyz)]•CuCN (Fig. 13C), 2[(CuCN)2(4,4′-Bpy)]•3CuCN, [(CuCN)2(4,4′-
Bpy)]•2CuCN, 2[(CuCN)2(RPip)]•3CuCN (RPip = N-methyl- or N-ethylpiperazine), and
[(CuCN)2(R2Pip)]•2CuCN (R = N,N′-dimethyl- or N,N′-diethylpiperazine).40,99,101 Cuprophilic
interactions between sub-lattices are the rule in these structures. A unique binary network,
(CuCN)20(Pip)7 = 6[(CuCN)2(Pip)]•[(CuCN)8(Pip)] incorporates two interpenetrating tiled sheet sub-
lattices: a simple (6,3) planar network of stoichiometry (CuCN)2(Pip), and an unusual (CuCN)8(Pip)
which contains seven 2-coordinate Cu atoms.40,102 All twenty copper atoms in (CuCN)20(Pip)7 are
crystallographically independent. An alternative to sheet formation in 3-coordinate networks involves
bridging between CuCN chains that propagate in perpendicular directions.103 The resulting 3-D
networks sometimes contain helical CuCN chains.
Figure 13. (A) (CuCN)2(phthalazine) structure showing ladder motif.91 (B) (CuCN)(1,4-bis(2-
pyrimidinesulfanylmethyl)benzene) structure showing 4-coordinate Cu4(CN)2L2 rings.100b (C) Structure
of [(CuCN)2(Pyz)]•CuCN threading of CuCN through a (6,3) network.99
The addition of chelation96,104 or sulfur atom bridging85a,105 by the ligands into the 2-D networks
described above increases the variety of possible motifs. A particularly interesting example is provided
using a triply-bridging chelate hexaazatriphenylene ligand which produces a tethering node for the
23
CuCN chains.106 The structure shown in Fig. 14A contains widely separated chains tethered together to
form a nanoporous hexagonal network that entrains solvent molecules (THF, Pyz, 1,4-dioxane). A
common way in which 3-D networks are formed from the 2-D sheets described above is through the
formation of 3-C,C,N-bridged dimer units with cuprophilic interactions, XXVI (see Fig.
14B).83b,93m,98b,98f,99,103a,107 The formation of these networks is rather difficult to anticipate, since closely
related or even identical ligands can produce both 2-D and 3-bridged 3-D arrangements. This is clearly
illustrated in Zubieta’s extensive structural study of pyrazine-based ligands.99 He found simple 2-D
sheets for (CuCN)3(Pyz), (CuCN)2(2-EtPyz), (CuCN)2(2,3,5,6-Me4Pyz)], (CuCN)2(quinoxaline), and
(CuCN)2(phenazine), but observed 3-D 3-C,C,N-bridged dimer-linked networks for (CuCN)2(2-
MePyz), (CuCN)2(2,3-Me2Pyz), (CuCN)2(2,5-Me2Pyz), and (CuCN)2(2,6-Me2Pyz).
Figure 14. (A) (CuCN)3(3,7,11-triethoxy-2,6,10-tricyanohexaazatriphenylene)•THF structure. Position
of disordered THF molecule indicated by large green sphere.106 (B) (CuCN)2(1,4-butanediamine)
structure, showing 3-C,C,N cyano bridges.98b (C) (CuCN)Pyz structure, showing 4-coordinate
diamondoid arrangement.108b
Another important 3-D motif for CuCN complexes with bridging bidentate ligands is the diamondoid
network (see Fig. 14C).98a,108 In this case copper centers are 4-coordinate and are linked by cyano units
and bridging ligands in orthogonal directions. In addition to the 2-D and 3-bridged 3-D pyrazine
networks described above, both Pyz and 2-MePyz also form diamondoid networks, and Pyz itself also
forms yet another diamondoid network, (CuCN)3(Pyz)2 which contains both 2- and 4-coordinate copper
24
centers.99 Since the diamondoid net tends to be a porous in nature, especially with relatively long ligand
bridges, interpenetration of multiple sub-lattices is common. Instead of self-interpenetrating, the
diamondoid [(CuCN)(4,4'-Bpy)]•2(4,4'-Bpy) incorporates two free ligand molecules within its
channels.98c,98g,99
Multidentate ligands produce a range of stoichiometries and network structures that is too large to
tackle here.74,83b,90,104e,109 As an example, let us consider the complexes of CuCN with the potentially
tetradentate, adamantane-like HTMA ligand.40,98b Three phases are known: (CuCN)3(HMTA)2,
(CuCN)5(HMTA)2, and (CuCN)5(HMTA), see Fig. 15. These correspond to bi-, tri-, and tetradentate
bridging modes of the HMTA. They also reflect some of the variety of CuCN network formation. The
3:2 complex contains only 3-coordinate Cu atoms forming chains that are bridged by 2-HMTA, giving
rise to 2-D sheets consisting of Cu4 and Cu6 rings. In contrast, both the 5:2 and 5:1 complexes are 3-D
networks as the result of both 3-C,C,N bridges and polydentate ligand behavior. The 5:2 complex also
contains a 4-coordinate Cu center, while the 5:1 complex features a 2-coordinate Cu center.
Nevertheless, and presumably as a result of the steric constraints resulting from the crowding three or
four copper atoms around each HMTA, all the other Cu centers in the 5:2 and 5:1 complexes are part of
3-C,C,N dimers.
25
Figure 15. (A) (CuCN)3(HMTA)2 structure, showing sheet structure.98b (B) and (C) (CuCN)5(HMTA)2
and (CuCN)5(HMTA) structures, showing 3-C,C,N cyano bridges and increased network crowding
around the higher-coordinate ligand.40 Only a single layer of 3-D structure is shown in (B) and (C).
Conclusions
Although the reaction of copper with CO has been known for a very long time, the number of isolated
copper carbonyl complexes is still fairly modest, at least in part due to the relative lability of the Cu−CO
bond. Terminal and bridged species are recognized. Carbonyl is most commonly attached to amine-
bearing copper(I) centers, sometimes allowing unusual five-coordination. The bonding in Cu−CO
complexes, as evaluated through IR spectroscopy, spans a range from strongly -backbonding to
virtually -donor-only behavior. This latter bonding mode for CO is poorly studied, and could be of
interest in biological and/or environmental chemistry. The ability of aqueous Cu(I) solutions to scrub
CO efficiently is an interesting and long-recognized phenomenon that might yet have technological
applications.
Cyanide is almost the ideal network-forming ligand for copper(I). The simple, nearly linear chain
structure of CuCN is elaborated into an astounding array of 1-D, 2-D, and 3-D networks through
variable coordination number of Cu(I), variable modes of cyanide bridging, and the addition of various
organic ligands. Nitrogen, phosphorus, and sulfur donors react readily with CuCN, and even
coordination of oxygen donors, although rare, is known. Monodentate donors readily and reversibly
decorate CuCN chains, while bidentate bridging ligands produce tiled sheets or diamondoid networks.
Additional network cross-linking often results from the 3-C,C,N cyano bridge, which is usually
accompanied by cuprophilic interaction. Copper(I) compounds, including a great many cyano
complexes, tend to be photoluminescent through excitation of a 3d-electron into the 4s or a ligand *
orbital. Given the current intense interest in network chemistry in separations, molecular storage,
26
electronics, and sensing, the ability to modulate emission response in copper(I) cyanide networks will
continue to make them very attractive topics for research.
Abbreviation List: bpen = trans-1,2-bis(2-pyridyl)ethylene, Bpy = dipyridyl, Cy = cyclohexyl, cyclam =
1,4,8,11-tetraazacyclotetradecane, DFT = density functional theory, dmen = N,N-
dimethylethylenediamine, dppe = 1,2-bis(diphenylphosphino)ethane, DMF = N,N-dimethylformamide,
DMSO = Dimethyl sulfoxide, en = ethylenediamine, HMTA = hexamethylenetetramine, IR = infrared,
MeIm = methylimidazole, Morph = morpholine, Phen = o-phenanthroline, Pipd = piperidine, Pipz =
piperazine, Py = pyridine, Pyz = pyrazine, Quin = quinoline, THF = tetrahydrofuran, tmen = N,N,N'N'-
tetramethylethylenediamine, Tp = tris(pyrazolyl)borate.
ACKNOWLEDGMENT We thank the National Science Foundation (CHE-0848109) for support of
this work.
REFERENCES
1) Pérez, P. J.; Díaz-Requejo, M. M. In: Comprehensive Organometallic Chemistry III; Crabtree, R.
H.; Mingos, D. M. P., Eds.; Elsevier, Oxford, U.K., 2007; Chapter 2.03, Pages 153-195.
2) Mukherjee, R. In: Comprehensive Coordination Chemistry II, McCleverty J. A.; Meyer, T. J.
Eds, Pergamon, Oxford, 2003; Chapter 6.6, Pages 747-910.
3) (a) Scandola, F.; Argazzi, R.; Bignozzi, C. A.; Chiorboli, C.; Indelli, M. T.; Rampi, M. A.
Coord. Chem. Rev. 1993, 125, 283-292. (b) Dunbar, K. R.; Heintz, R. A. Prog. Inorg. Chem.
1997, 45, 283-391. (c) Beltran, L. M. C.; Long, J. R. Acc. Chem. Res. 2005, 38, 325-334. (d)
Culp, J. T.; Park, J.-H.; Frye, F.; Huh, Y.-D.; Meisel, M. W.; Talham, D. R. Coord. Chem. Rev.
2005, 249, 2642-2648. (e) Liu, S.; Poplaukhin, P.; Ding, E.; Plecnik, C. E.; Chen, X.; Keane, M.
27
A.; Shore, S. G. J. Alloys Compds. 2006, 418, 21-26. (f) Shatruk, M.; Avendano, C.; Dunbar, K.
R. Prog. Inorg. Chem. 2009, 56, 155-334.
4) (a) Backen, W.; Vestin, R. Acta Chem. Scand. 1979, A33, 85-91. (b) Pasquali, M.; Florinani, C.;
Gaetani-Manfredotti, A. A. Inorg. Chem. 1981, 20, 3382-3388. (c) Hakansson, M.; Jagner, S.
Inorg. Chem. 1990, 29, 5241-5244. (d) Peng, X. D.; Golden, T. C.; Pearlstein, R. M.;
Pierantozzi, R. Langmuir 1995, 11, 534-537.
5) Capracotta, M. D.; Sullivan, R. M.; Martin, J. D. J. Am. Chem. Soc. 2006, 128, 13463-13473.
6) Rack, J. J.; Webb, J. D.; Strauss, S. H. Inorg. Chem. 1996, 35, 277-278.
7) Polyakov, O. G.; Ivanova, S, M.; Gaudinski, C. M.; Miller, S. M.; Anderson, O. P.; Strauss, S.
H. Organometallics 1999, 18, 3769-3771.
8) Ivanova, S. M.; Ivanov, S. V.; Miller, S. M.; Anderson, O. P.; Solntsev, K. A.; Strauss, S. H.
Inorg. Chem. 1999, 38, 3756-3757.
9) Zhou, M.; Andrews. L. J. Chem. Phys. 1999, 111, 4548-4557.
10) (a) Pasquali, M.; Fiaschi, P.; Floriani, C.; Zanazzi, P. F. Chem. Commun. 1983, 613-614. (b)
Floriani, C.; Fiaschi, P.; Chiesi-Villa, A.; Guastini, C.; Zanazzi, P. F. J. Chem. Soc., Dalton
Trans. 1988, 1607-1615.
11) Geerts, R. L.; Huffman, J. C.; Folting, K.; Lemmen, T. H.; Caulton, K. G. J. Am. Chem. Soc.
1983, 105, 3503-3506.
12) Karlin, K. D.; Farooq, A.; Gultneh, Y.; Hayes, J. C.; Zubieta, J. Inorg. Chim. Acta 1988, 153, 73-
74.
13) (a) Lopes, C.; Hakansson, M.; Jagner, S. Inorg. Chem. 1997, 36, 3232-3236. (b) Lopes, C.;
Hakansson, M.; Jagner, S. New J. Chem. 1997, 21, 1113-1118.
28
14) (a) Polyakov, O. G.; Nolan, B. G.; Fauber, B. P.; Miller, S. M.; Anderson, O. P.; Strauss, S. H.
Inorg. Chem. 2000, 39, 1735-1742. (b) Dell'Amico, D. B.; Alessio, R.; Calderazzo, F.; Pina, F.
D.; Englert, U.; Pampaloni, G.; Passarelli, V. J. Chem. Soc., Dalton Trans. 2000, 2067-2075. (c)
(d) Sevryugina, Y.; Petrukhina, M. A. Z. Kristallogr. 2009, 224, 229-232.
15) (a) Doyle, G.; Eriksen, K. A.; van Engen, D. Inorg. Chem. 1983, 22, 2892-2895. (b) Dell'Amico,
D. B.; Calderazzo, F.; Labella, L.; Lorenzini, F.; Marchetti, F. Z. Anorg. Allg. Chem. 2002, 628,
1868-1872.
16) Klaui, W.; Lenders, B.; Hessner, B.; Evertz, K. Organometallics 1988, 7, 1357-1363.
17) (a) Pasquali, M.; Marchetti, F.; Floriani, C. Inorg. Chem. 1978, 17, 1684-1688. (b) Pasquali, M.;
Floriani, C.; Manfredotti, A. G. Inorg. Chem. 1980, 19, 1191-1197. (c) Shimazaki, Y.; Nogami,
T.; Tani, F.; Odani, A.; Yamauchi, O. Angew. Chem., Int. Ed. 2001, 40, 3859-3862. (d) Osako,
T.; Terada, S.; Tosha, T.; Nagatomo, S.; Furutachi, H.; Fujinami, S.; Kitagawa, T.; Suzuki, M.;
Itoh, S. Dalton Trans. 2005, 3514-3521. (e) Kunishita, A.; Osako, T.; Tachi, Y.; Teraoka, J.;
Itoh, S. Bull. Chem. Soc. Jpn. 2006, 79, 1729-1741. (f) Kujime, M.; Kurahashi, T.; Tomura, M.;
Fujii, H. Inorg. Chem. 2007, 46, 541-551. (g) Kajita, Y.; Arii, H.; Saito, T.; Saito, Y.; Nagatomo,
S.; Kitagawa, T.; Funahashi, Y.; Ozawa, T.; Masuda, H. Inorg. Chem. 2007, 46, 3322-3335. (h)
Zhou, L.; Powell, D.; Nicholas, K. M. Inorg. Chem. 2007, 46, 7789-7799. (i) Fry, H. C.; Lucas,
H. R.; Sarjeant, A. A. N.; Karlin, K. D.; Meyer, G. J. Inorg. Chem. 2008, 47, 241-256. (j)
Cushion, M.; Ebrahimpour, P.; Haddow, M. F.; Hallett, A. J.; Mansell, S. M.; Orpen, A. G.;
Wass, D. F. Dalton Trans. 2009, 1632-1653. (k) Green, O.; Gandhi, B. A.; Burstyn, J. N. Inorg.
Chem. 2009, 48, 5704-5714. (l) Ebrahimpour, P.; Cushion, M.; Haddow, M. F.; Hallett, A. J.;
Wass, D. F. Dalton Trans. 2010, 39, 10910-10919. (m) Lucas, H. R.; Meyer, G. J.; Karlin, K. D.
J. Am. Chem. Soc. 2010, 132, 12927-12940.
29
18) (a) Pasquali, M.; Marini, G.; Floriani, C.; Manfredotti, A. G.; Guastini, C. Inorg. Chem. 1980,
19, 2525-2531. (b) Gagne, R. R.; Kreh, R. P.; Dodge, J. A.; Marsh, R. E.; McCool, M. Inorg.
Chem. 1982, 21, 254-261. (c) Patch, M. G.; Choi, H.-K.; Chapman, D. R.; Bau, R.; McKee, V.;
Reed, C. A. Inorg. Chem. 1990, 29, 110-119. (d) Karlin, K. D.; Tyeklar, Z.; Farooq, A.; Haka,
M. S.; Ghosh, P.; Cruse, R. W.; Gultneh, Y.; Hayes, J. C.; Toscano, P. J.; Zubieta, J. Inorg.
Chem. 1992, 31, 1436-1451. (e) Schindler, S.; Szalda, D. J.; Creutz, C. Inorg. Chem. 1992, 31,
2255-2264. (f) Ardizzoia, G. A.; Beccalli, E. M.; La Monica, G.; Masciocchi, N.; Moret, M.
Inorg. Chem. 1992, 31, 2706-2711. (g) Mahapatra, S.; Kaderli, S.; Llobet, A.; Neuhold, Y.-M.;
Palanche, T.; Halfen, J. A.; Young, V. G., Jr.; Kaden, T. A.; Que, T., Jr.; Zuberbuhler, A. D.;
Tolman, W. B. Inorg. Chem. 1997, 36, 6343-6356. (h) Costas, M.; Xifra, R.; Llobet, A.; Sola,
M.; Robles, J.; Parella, T.; Stoeckli-Evans, H.; Neuburger, M. Inorg. Chem. 2003, 42, 4456-
4468. (i) Chou, C.-C.; Su, C.-C.; Yeh, A. Inorg. Chem. 2005, 44, 6122-6128. (j) Fujisawa, K.;
Noguchi, Y.; Miyashita, Y.; Okamoto, K.; Lehnert, N. Inorg. Chem. 2007, 46, 10607-10623.
19) (a) Kitagawa, S.; Matsuyama, S.; Munakata, M.; Emori, T. J. Chem. Soc., Dalton Trans. 1991,
2869-2874. (b) Singh, K.; Long, J. R.; Stavropoulos, P. Inorg. Chem. 1998, 37, 1073-1079. (c)
Maekawa, M.; Konaka, H.; Minematsu, T.; Kuroda-Sowa, T.; Munakata, M.; Kitagawa, S.
Chem. Commun. 2007, 5179-5181.
20) Achternbosch, M.; Apfel, J.; Fuchs, R.; Klufers, P.; Selle, A. Z. Anorg. Allg. Chem. 1996, 622,
1365-1373.
21) Fianchini, M.; Cundari, T. R.; DeYonker, N. J.; Dias, H. V. R. Dalton Trans. 2009, 2085-2087.
22) (a) Gagné, R. R.; Allison, J. L.; Gall, R. S.; Koval, C. A. J. Am. Chem. Soc. 1977, 99, 7170-
7178. (b) Gagné, R. R.; Allison, J. L.; Ingle, D. M. Inorg. Chem. 1979, 18, 2767-2774. (c)
McCool, M. W.; Marsh, R. E.; Ingle, D. M.; Gagné, R. R. Acta Crystallogr., Sect. B 1981, 37,
935-937. (d) Gagné, R. R.; Ingle, D. M.; Lisensky, G. C. Inorg. Chem. 1981, 20, 1991-1993.
30
23) Chu, L.; Hardcastle, K. I.; MacBeth, C. E. Inorg. Chem. 2010, 49, 7521-7529.
24) (a) Bruce, M. I.; Ostazewski, A. P. P. J. Chem. Soc., Chem. Commun. 1972, 1124-1125. (b)
Kitajima, N.; Fujisawa, K.; Fujimoto, C.; Moro-oka, Y.; Hashimoto, S.; Kitagawa, T.; Toriumi,
K.; Tatsumi, K.; Nakamura, A. J. Am. Chem. Soc. 1992, 114, 1277-1291. (c) Dias, H. V. R.; Lu,
H.-L. Inorg. Chem. 1995, 34, 5380-5382. (d) Dias, H. V. R.; Kim, H.-J.; Lu, H.-L.; Rajeshwar,
K.; de Tacconi, N. R.; Derecskei-Kovacs, A.; Marynick, D. S. Organometallics 1996, 15, 2994-
3003. (e) Dias, H. V. R.; Kim, H.-J. Organometallics 1996, 15, 5374-5379. (f) Kiani, S.; Long, J.
R.; Stavropoulos, P. Inorg. Chim. Acta 1997, 263, 357-366. (g) Imai, S.; Fujisawa, K.;
Kobayashi, T.; Shirasawa, N.; Fujii, H.; Yoshimura, T.; Kitajima, N.; Moro-oka, Y. Inorg.
Chem. 1998, 37, 3066-3073. (h) Conry, R. R.; Ji, G.; Tipton, A. A. Inorg. Chem. 1999, 38, 906-
913. (i) Blake, A. J.; Carling, D. A.; George, M. W.; Hubberstey, P.; Garcia, R. L.; Wilson, C.
Acta Crystallogr., Sect. E 2002, 58, m41-m42. (j) Dias, H. V. R.; Goh, T. K. H. H. Polyhedron
2004, 23, 273-282. (k) Papish, E. T.; Donahue, T. M.; Wells, K. R.; Yap, G. P. A. Dalton Trans.
2008, 2923-2925. (l) Despagnet-Ayoub, E.; Jacob, K.; Vendier, L.; Etienne, M.; Alvarez, E.;
Caballero, A.; Diaz-Requejo, M. M.; Perez, P. J. Organometallics 2008, 27, 4779-4787. (m)
Fujisawa, K.; Yoshida, M.; Miyashita, Y.; Okamoto, K. Polyhedron 2009, 28, 1447-1454. (n)
Kou, X.; Wu, J.; Cundari, T. R.; Dias, H. V. R. Dalton Trans. 2009, 915-917. (o) King, W.A.;
Yap, G. P. A.; Incarvito, C. D.; Rheingold, A. L.; Theopold, K. H. Inorg. Chim. Acta 2009, 362,
4493-4499.
25) Fujisawa, K.; Ono, T.; Ishikawa, Y.; Amir, N.; Miyashita, Y.; Okamoto, K.; Lehnert, N. Inorg.
Chem. 2006, 45, 1698-1713.
26) (a) Villacorta, G. M.; Lippard, S. J. Inorg. Chem. 1987, 26, 3672-3676. (b) Dias, H. V. R.;
Singh, S. Inorg. Chem. 2004, 43, 5786-5788. (c) Hill, L. M. R.; Gherman, B. F.; Aboelella, N.
W.; Cramer, C. J.; Tolman, W. B. Dalton Trans. 2006, 4944-4953. (d) Dias, H. V. R.; Singh, S.;
Flores, J. A. Inorg. Chem. 2006, 45, 8859-8861.
31
27) (a) Reger, D. L; Collins, J. E.; Rheingold, A. L; Liable-Sands, L. M. Organometallics 1996, 15,
2029-2032. (b) Miller, K. E.; Schopp, L. M.; Nesseth, K. N.; Moore, C.; Rheingold, A. L.;
Daley, C. J. A. Acta Crystallogr., Sect. E 2009, 65, m1354-m1355.
28) (a) Rucci, G.; Zanzottera, C.; Lachi, M. P.; Camia, M. J. Chem. Soc., Chem. Commun. 1971,
652-652. (b) Thompson, J. S.; Whitney, J. F. Inorg. Chem. 1984, 23, 2813-2819. (c) Toth, A.;
Floriani, C.; Pasquali, M.; Chiesi-Villa, A.; Gaetani-Manfredotti, A.; Guastini, C. Inorg. Chem.
1985, 24, 648-653. (d) Stamp, L.; tom Dieck, H. Inorg. Chim. Acta 1987, 129, 107-114. (e)
Ugozzoli, F.; Lanfredi, A. M. M.; Marsich, N.; Camus, A. Inorg. Chim. Acta 1997, 256, 1-7. (f)
Pampaloni, G.; Peloso, R.; Belletti, D.; Graiff, C.; Tiripicchio, A. Organometallics 2007, 26,
4278-4286.
29) Pasquali, M.; Marini, G.; Floriani, C.; Manfredotti, A. G. Chem. Commun. 1979, 937-938.
30) Wiles, A. B.; Pike, R. D. Organometallics 2006, 25, 3282-3285.
31) (a) Pasquali, M.; Floriani, C.; Manfredotti, A. G.; Guastini, C. J. Am. Chem. Soc. 1981, 103,
185-186. (b) Pasquali, M.; Floriani, C.; Venturi, G.; Manfredotti, A. G.; Villa, A. C. J. Am.
Chem. Soc. 1982, 104, 4092-4099. (c) Doyle, G.; Eriksen, K. A.; Modrick, M.; Ansell, G.
Organometallics 1982, 1, 1613-1618.
32) Liang, F.-P.; Qin, S.-N.; Jiang, C.-F.; Zhang, Z.; Chen, Z.-L. Organometallics 2007, 26, 4839-
4842.
33) (a) Shieh, M.; Miu, C.-Y.; Lee, C.-J.; Chen, W.-C.; Chu, Y.-Y.; Chen, H.-L. Inorg. Chem. 2008,
47, 11018-11031.
34) (a) Sculfort, S.; Croizat, P.; Messaoudi, A.; Benard, M.; Rohmer, M.-M.; Welter, R.; Braunstein,
P. Angew. Chem., Int. Ed. 2009, 48, 9663-9667. (b) Sculfort, S.; Welter, R.; Braunstein, P.
Inorg. Chem. 2010, 49, 2372-2382.
32
35) (a) Izatt, R. M.; Johnston, H. D.; Watt, G. D.; Christensen, J. J. Inorg. Chem. 1967, 6, 132-135.
(b) Yamamoto, T.; Haraguchi, H.; Fujiwara, S. J. Phys. Chem. 1970, 74, 4369-4373. (c) Lu, J.;
Dreisinger, D. B.; Cooper, W. C. Hydrometallurgy 2002, 66, 23-36.
36) Hibble, S. J.; Eversfield, S. G.; Cowley, A. R.; Chippindale, A. M. Angew. Chem. Int. Ed. 2004,
43, 628-630.
37) Hibble, S. J.; Cheyne, S. M.; Hannon, A. C.; Eversfield, S. G. Inorg. Chem. 2002, 41, 4990-
4992.
38) Reckeweg, O.; Lind, C.; Simon, A.; DeSalvo, F. J. Z. Naturforsch. B 2003, 58, 155-158.
39) Bowmaker, G. A.; Kennedy, B. J.; Reid, J. C. Inorg. Chem. 1998, 37, 3968-3974.
40) Lim, M. J.; Murray, C. A.; Tronic, T. A.; deKrafft, K. E.; Ley, A. N.; deButts, J. C.; Pike, R. D.;
Lu, H.; Patterson, H. H. Inorg. Chem. 2008, 47, 6931-6947.
41) (a) Bayse, C. A.; Brewster, T. P.; Pike, R. D. Inorg. Chem. 2009, 48, 174-182. (b) Bayse, C. A.;
Ming, J. L.; Miller, K. M.; McCullough, S. M.; Pike, R. D. Inorg. Chim. Acta 2011, 375, 47-52.
42) (a) Horváth, A.; Zsilák, Z.; Papp, S. J. Photochem. Photobiol. A 1989, 50, 129-139. (b) Horváth,
A.; Stevenson, K. L. Inorg. Chem. 1993, 32, 2225-2227. (c) Horváth, A.; Wood, C. E.;
Stevenson, K. L. J. Phys. Chem. 1994, 98, 6490-6495. (d) Horváth, A.; Wood, C. E.; Stevenson,
K. L. Inorg. Chem. 1994, 33, 5351-5354. (e) Horváth, A.; Stevenson, K. L. Coord. Chem. Rev.
2000, 208, 139-151.
43) Dembo, M. D.; Dunaway, L. E.; Jones, J. S.; Lepekhina, E. A.; McCullough, S. M.; Ming, J. L.;
Li, X.; Baril-Robert, F.; Patterson, H. H.; Bayse, C. A.; Pike, R. D. Inorg. Chim. Acta 2010, 364,
102-114.
33
44) (a) Stevenson, K. L.; Bell, P. B.; Watson, R. E. Coord. Chem. Rev. 2002, 229, 133-146. (b)
Stevenson, K. L.; Jarboe, J. H. J. Photochem. Photobiol. A 2002, 150, 49-57. (c) Stevenson, K.
L.; Jarboe, J. H.; Langmeyer, S. A.; Acra, T. W. Inorg. Chem. 2003, 42, 3559-3564.
45) Bowmaker, G. A.; Hartl, H.; Urban, V. Inorg. Chem. 2000, 39, 4548-4554.
46) Fuchiwaki, J.; Nishikiori, S.-I. Chem. Lett. 2010, 39, 598-600.
47) (a) Bowmaker, G. A.; Lim, K. C.; Skelton, B. W.; White, A. H. Z. Naturforsch. B 2004, 59,
1264-1276. (b) Bowmaker, G. A.; Hart, R. D.; Skelton, B. W.; White, A. H. Z. Naturforsch. B
2004, 59, 1293-1300. (c) Bowmaker, G. A.; Lim, K. C.; Somers, N.; Skelton, B. W.; White, A.
H. Z. Naturforsch. B 2004, 59, 1301-1306.
48) Kettle, S. F. A.; Diana, E.; Boccaleri, E.; Stanghellini, P. L. Inorg. Chem. 2007, 46, 2409-2416.
49) (a) Ellermann, J.; Knoch, F. A.; Meier, K. J.; Moll, M. J. Organomet. Chem. 1992, 428, C44-
C51. (b) Saravanabharathi, D.; Monika; Venugopalan, P.; Samuelson, A. G. Polyhedron 2002,
21, 2433-2443. (c) Kamte, M. F.; Wagner, C.; Schaefer, W. J. Coord. Chem. 2004, 57, 55-60.
(d) Kamte, M. F.; Wagner, C.; Schaefer, W. Anal. Sci.: X-Ray Struct. Anal. Online 2005, 21, x5-
x7. (e) Effendy, di Nicola, C.; Pettinari, C.; Pizzabiocca, A.; Skelton, B. W.; Somers, N.; White,
A. H. Inorg. Chim. Acta 2006, 359, 64-80. (f) Wang, R.; Xiao, Y.-L.; Jin, Q.-H.; Zhang, C.-L.
Acta Crystallogr., Sect. E 2010, 66, m1032-m1032.
50) (a) Ogura, T.; Shemesh, E.; Scott, N.; Pyrka, G. J.; Fernando, Q. Inorg. Chim. Acta 1988, 149,
57-62. (b) Dunaj-Jurco, M.; Potocnak, I.; Cibik, J.; Kabesova, M.; Kettmann, V.; Miklos, D.
Acta Crystallogr., Sect. C 1993, 49, 1476-1479. (c) Lim, B. S.; Holm, R. H. Inorg. Chem. 1998,
37, 4898-4908.
51) (a) Asplund, M.; Jagner, S.; Nilsson M. Acta Chem. Scand. A 1983, 37, 165-168. (b) Fortman, G.
C.; Slawin, A. M. Z.; Nolan, S. P. Organometallics 2010, 29, 3966-3972.
34
52) (a) Chaudhuri, P.; Oder, K.; Wieghardt, K.; Weiss, J.; Reedijk, J.; Hinrichs, W.; Wood, J.
Ozarowski, A.; Stratemaier, H.; Reinen, D. Inorg. Chem. 1986, 25, 2951-2958. (b) Inoue, M. B.;
Machi, L.; Inoue, M.; Fernando, Q. Inorg. Chim. Acta 1992, 192, 123-128. (c) Marlin, D. S.;
Olmstead, M. M.; Mascharak, P. K. Angew. Chem., Int. Ed. 2001, 40, 4752-4754. (d) Kocanova,
I.; Kuchar, J.; Orendac, M.; Cernak, J. Polyhedron 2010, 29, 3372-3379.
53) Roof, R. B., Jr.; Larsen, A. C.; Cromer, D. T. Acta Crystallogr., Sect. B 1968, 24, 269-273.
54) (a) Muller, A.; Dartmann, M.; Romer, C.; Clegg, W.; Sheldrick, G. M. Angew. Chem., Int. Ed.
1981, 20, 1060-1061. (b) Gheller, S. F.; Hambley, T. W.; Rodgers, J. R.; Brownlee, R. T. C.;
O’Connor, M. J.; Snow, M. R.; Wedd, A. G. Inorg. Chem. 1984, 23, 2519-2528. (c) Shaowu, D.;
Nianyong, Z.; Pengcheng, C.; Xintao, W.; Jiaxi, L. Polyhedron 1992, 11, 109-113. (d) Shaowu,
D.; Nianyong, Z.; Pengcheng, C.; Xintao, W.; Jiaxi, L. J. Chem. Soc., Dalton Trans. 1992, 339-
344. (e) Salm, R. J.; Ibers, J. A. Inorg. Chem. 1994, 33, 4216-4220. (f) Lang, J.-P.; Xu, Q.-F.; Ji,
W.; Elim, H. I.; Tatsumi, K. Eur. J. Inorg. Chem., 2004, 86-92. (g) Rao, P. V.; Bhaduri, S.;
Jiang, J.; Holm, R. H. Inorg. Chem. 2004, 43, 5833-5649. (h) Takuma, M.; Ohki, Y.; Tatsumi,
K. Inorg. Chem. 2005, 44, 6034-6043. (i) Ren, Z.-G.; Li, H.-X.; Li, L.-L.; Zhang, Y.; Lang, J.-P.;
Yang, J.-Y.; Song, Y.-L. J. Organomet. Chem. 2007, 692, 2205-2215. (j) Zhang, W.-H.; Song,
Y.-L.; Zhang, Y.; Lang, J.-P. Cryst. Growth Des. 2008, 8, 253-258. (k) Llusar, R.; Sorribes, I.;
Vicent, C. Inorg. Chem. 2009, 48, 4837-4846. (l) You, X.-L.; Liu, Y.-L. Acta Crystallogr., Sect.
E 2009, 65, m1485-m1485.
55) Pickardt, J.; Staub, B. Z. Naturforsch. B 1999, 54, 329-336.
56) Lin, Y.-Y.; Lai, S.-W.; Che, C.-M.; Fu, W.-F.; Zhou, Z.-Y.; Zhu, N. Inorg. Chem. 2005, 44,
1511-1524.
57) Potočňák, I.; Dunaj-Jurčo, M.; Kabešová, M. Acta Crystallogr., Sect. C 1994, 50, 380-383. (b)
Yuge, H.; Soma, T.; Miyamoto, T. K. Collect. Czech. Chem. Commun. 1998, 63, 622-627. (c)
35
Pickardt, J.; Staub, B.; Schäfer, K. O. Z. Anorg. Allg. Chem. 1999, 625, 1217-1224. (d) Pretsch,
T.; Ostmann, J.; Donner, C.; Nahorska, M.; Mroziński, J.; Hartl, H. Inorg. Chim. Acta 2005,
358, 2558-2564. (e) Weiss, R.; Jansen, G.; Boese, R.; Epple, M. Dalton Trans. 2006, 1831-1835.
58) (a) Olmstead, M. M.; Speier, G.; Szabo, L. Chem. Commun. 1994, 541-543. (b) Gunther, M.;
Schafer, W.; Stettler, A.; Hartung, H. Z. Anorg. Allg. Chem. 2000, 626, 655-660. (c) Kamte, M.
F.; Baumeister, U.; Schafer, W. Z. Anorg. Allg. Chem. 2003, 629, 1919-1924. (d) Naito, T.;
Nishibe, K.; Inabe, T. Z. Anorg. Allg. Chem. 2004, 630, 2725-2730. (e) Kovbasyuk, L.;
Pritzkow, H.; Kramer, R. Eur. J. Inorg. Chem. 2005, 894-900.
59) (a) Cromer, D. T. J. Phys. Chem. 1957, 61, 1388-1392. (b) Kappenstein, C.; Hugel, R. Inorg.
Chem. 1977, 16, 250-254.
60) (a) Cromer, D. T.; Larson, A. C. Acta. Crystallogr. 1962, 15, 397-403. (b) Pohl, A. H.;
Chippindale, A. M.; Hibble, S. J. Solid State Sci. 2006, 8, 379-387.
61) (a) Yamochi, H.; Komatsu, T.; Matsukawa, N.; Saito, G.; Mori, T.; Kusunoki, M.; Sakaguchi, K.
J. Am. Chem. Soc. 1993, 115, 11319-11327. (b) Zhao, Y.; Hong, M.; Su, W.; Cao, R.; Zhou, Z.;
Chan, A. S. C. J. Chem. Soc., Dalton Trans. 2000, 1685-1686. (c) Pretsch, T.; Brüdgam, I.;
Hartl, H. Z. Anorg. Allg. Chem. 2003, 629, 942-944. (d) Pretsch, T.; Brüdgam, I.; Hartl, H. Z.
Anorg. Allg. Chem. 2004, 630, 353-360. (e) Pretsch, T.; Hartl, H. Z. Anorg. Allg. Chem. 2004,
630, 1581-1588. (f) Yun, S.-S.; Moon, H.-S.; Kim, C.-H.; Lee, S.-G. J. Coord. Chem. 2004, 57,
321-327. (g) Lin, S.-H.; Zhou, X.-P.; Li, D.; Ng, S. W. Cryst. Growth Des. 2008, 8, 3879-3881.
62) Siebel, E.; Schwarz, P.; Fischer, R. D. Solid State Ionics 1997, 101-103, 285-292.
63) (a) Cernak, J.; Gyoryova, K.; Sabolova, S.; Dunaj-Jurčo, M. Inorg. Chim. Acta 1991, 185, 119-
125. (b) Qin, Y.-L.; Hou, J.-J.; Lv, J.; Zhang, X.-M. Cryst. Growth Des. 2011, 11, 3101-3108.
64) Williams, R. J.; Larsen, A. C.; Cromer, D. T. Acta Crystallogr., Sect. B 1972, 28, 858-864.
36
65) Colacio, E.; Kivekäs, R.; Lloret, F.; Sunberg, M.; Suarez-Varela, J.; Bardají, M.; Laguna, A.
Inorg. Chem. 2002, 41, 5141-5149.
66) Chesnut, D. J.; Zubieta, J. Chem. Commun. 1998, 1707-1708.
67) (a) Peng, S.-M.; Liaw, D.-S. Inorg. Chim. Acta 1986, 113, L11-L12. (b) Zhao, X.-J.; Batten, S.
R.; Du, M. Acta Crystallogr., Sect. E 2004, 60, m1237-m1239. (c) Liu, B.; Xu, L.; Guo, G.-C.;
Huang, J.-S. Inorg. Chem. Commun. 2005, 8, 796-799.
68) Zhang, X.-M.; Qing, Y.-L.; Wu, H.-S. Inorg. Chem. 2008, 47, 2255-2257.
69) Inoue, M. B.; Inoue, M.; Machi, L.; Brown, F.; Fernando, Q. Inorg. Chim. Acta 1995, 230 145-
151.
70) Park, K.-M.; Lee, S.; Kang, Y.; Moon, S.-H.; Lee, S. S. Dalton Trans. 2008, 6521-6523.
71) Chippindale, A. M.; Cheyne, S. M.; Hibble, S. J. Angew. Chem. Int. Ed. 2005, 44, 7942-7946.
72) Chippindale, A. M.; Hibble, S. J.; Cowley, A. R. Inorg. Chem. 2004, 43, 8040-8048.
73) Liu, X.; Guo, G.-C.; Wu. A.-Q.; Cai, L.-Z.; Huang, J.-S. Inorg. Chem. 2005, 44, 4282-4286.
74) Chesnut, D. J.; Kusnetzow, A.; Birge, R.; Zubieta, J. Inorg. Chem. 1999, 38, 5484-5494.
75) Benmansour, S.; Setifi, F.; Triki, S.; Thétiot, F.; Sala-Pala, J.; Gómez-García, C. J.; Colacio, E.
Polyhedron 2009, 28, 1308-1314.
76) (a) Wasielewski, K.; Mattes, R. Z. Naturforsch. B 1992, 47, 1795-1797. (b) Huang, S. F.; Wei,
H. H.; Wang, Y. Polyhedron 1997, 16, 1747-1753. (c) Kou, H.-Z.; Zhou, B.C.; Wang, R.-J. J.
Organomet. Chem. 2004, 689, 369-373. (d) Kim, D.-H.; Koo, J.-E., Hong, C. S.; Oh, S.; Do, Y.
Inorg. Chem. 2005, 44, 4383-4390. (e) Jin, Y.; Che, Y.; Zheng, J. J. Coord. Chem. 2006, 59,
691-698. (f) Song, Y.; Xu, Y.; Wang, T.-W.; Wang, Z.-X.; You, X.-Z. J. Mol. Struct. 2006, 788,
206-210. (g) Zhan, S.-Z.; Wang, J.-G.; Song, Y.-Q.; Lv, Q.-Y.; Song, Y.; Su, J.-Y.; Yan, W.-Y.
37
Inorg. Chem. Commun. 2007, 10, 1019-1022. (h) Zhan, S.-Z.; Li, W.; Wang, J.-G.; Liang, A.-Q.;
Deng, Y.-F. J. Organomet. Chem. 2007, 692, 3568-3573. (i) Zhan, S.-Z.; Li, W.; Wang, B.-M.
Zhang, R.-L.; Kunag, W.-F. J. Coord. Chem. 2007, 60, 2747-2754.
77) Ley, A. N.; Dunaway, L. E.; Brewster, T. P.; Dembo, M. D.; Harris, T. D.; Baril-Robert, F.; Li,
X.; Patterson, H. H.; Pike, R. D. Chem. Commun. 2010, 46, 4565-4567.
78) Kidea, J. D.; Skelton, B. W.; White, A. H. Aust. J. Chem. 1985, 38, 1329-1334.
79) (a) Yu, L.; Lai, L.; Liu, S.; Xia, Y. Russ. J. Coord. Chem. 2010, 36, 120-123. (b) Cai, J.-B.;
Chem, T.-T.; Xie, Z.-Y.; Deng, H. Acta Crystallogr., Sect. E 2011, 67, m1136-m1137.
80) Etaiw, S. E. H.; Amer, S. A.; El-bendary, M. M. J. Mater. Sci. 2010, 45, 1307-1314.
81) In reference 78, the reported compound (CuCN)2Py is probably (CuCN)7Py4. In addition, the
compounds (CuCN)(2-MePy) and (CuCN)(2,4,6-Me3Py) are misreported as 2:1 species in this
reference.
82) (a) Cromer, D. T.; Larson, A. C.; Roof, R. B., Jr. Acta Crystallogr. 1965, 19, 192-197.
83) (a) Emokpae, D.; Ukwueze, A. C. Synth. React. Inorg. Met.-Org. Chem. 1986, 16, 387-396. (b)
He, X.; Lu, C.-Z.; Wu, C.-D.; Chen, L.-J. Eur. J. Inorg. Chem. 2006, 2491-2503. (c) Hang, T.;
Fu, D.-W.; Ye, Q. Acta Crystallogr., Sect. E 2007, 63, m3123-m3123. (d) Bowmaker, G. A.;
Hanna, J. V.; Hahn, F. E.; Lipton, A. S.; Oldham, C. E. Skelton, B. W.; Smith, M. E.; White, A.
H. Dalton Trans. 2008, 1710-1720. (e) Liu, X.; Guo, G.-C. Aust. J. Chem. 2008, 61, 481-483. (f)
Etaiw, S. E. H.; Amer, S. A.; El-bendary, M. M. Polyhedron 2009, 28, 2385-2390. (g) Etaiw, S.
E. H.; El-bendary, M. M. J. Inorg. Organomet. Polym. 2010, 20, 739-745.
84) Dyason, J. C.; Healy, P. C.; Engelhardt, L. M.; Pakawatchai, C.; Patrick, V. A.; White, A. H. J.
Chem. Soc., Dalton Trans. 1985, 839-844.
38
85) (a) Stocker, F. B.; Troester, M. A.; Britton, D. Inorg. Chem. 1996, 35, 3145-3153. (b) Stocker, F.
B.; Troester, M. A. Inorg. Chem. 1996, 35, 3154-3158.
86) Olbrich, R.; Kopf, J.; Weiss, E. J. Organomet. Chem. 1993, 456, 293-298.
87) Bowmaker, G. A.; Pettinari, C.; Skelton, B. W.; Somers, N.; Vigar, N. A.; White, A. H. Z.
Anorg. Allg. Chem. 2007, 633, 415-421.
88) Wang, H.; Li, M.-X.; Shao, M.; He, X. Polyhedron 2007, 26, 5171-5176.
89) Olmstead, M. M. Acta Crystallogr., Sect. C 1993, 49, 370-372.
90) Qiao, Y.-B.; Wang, K.-F.; Hu, L.-H.; Jian, F.-F. Chin. J. Chem. 2006, 24, 1144-1147.
91) Tronic, T. A.; deKrafft, K. E.; Lim, M. J.; Ley, A. N.; Pike, R. D. Inorg. Chem. 2007, 46, 8897-
8912.
92) Heller, M.; Sheldrick, W. S. Z. Anorg. Allg. Chem. 2001, 627, 569-571.
93) (a) Cooper, D.; Plane, R. A. Inorg. Chem. 1966, 5, 2209-2212. (b) Morpurgo, G. O.; Dessy, G.;
Fares, V. J. Chem. Soc., Dalton Trans. 1984, 785-791. (c) Dessy, G.; Fares, V.; Imperatori, P.;
Morpurgo, G. O. J. Chem. Soc., Dalton Trans. 1985, 1285-1288. (d) Goher, M. A. S.; Wang, R.-
J.; Mak, T. C. W. J. Coord. Chem. 1996, 38, 151-164. (e) Chesnut, D. J.; Kusnetzow, A.; Birge,
R.; Zubieta, J. J. Chem. Soc., Dalton Trans. 2001, 2581-2586. (f) Mao, H.; Zhang, C.; Xu, C.;
Zhang, H.; Shen, X.; Wu, B.; Zhu, Y.; Wu, Q.; Wang, H. Inorg. Chim. Acta 2005, 358, 1934-
1942. (g) He, X.; Lu, C.-Z.; Yuan, D.-Q.; Chen, S.-M.; Chen, J.-T. Eur. J. Inorg. Chem. 2005,
2181-2188. (h) Chen, X.-B.; Li, Y.-Z.; You, X.-Z. Appl. Organomet. Chem. 2006, 20, 305-309.
(i) Xua, Y.; Rena, Z.-G.; Lia, H.-X.; Zhang, W.-H.; Chen, J.-X.; Zhang, Y.; Lang, J.-P. J. Mol.
Struct. 2006, 782, 150-156. (j) Yan, B.; Golub, V. O.; Lachgar, A. Inorg. Chim. Acta 2006, 359,
118-126. (k) Lou, Z.-N.; Han, Z.-B.; Zhang, P. Struct. Chem. 2007, 18, 549-554. (l) Lin, S.-H.;
Yang, Y.-Y.; Ng, S. W. Acta Crystallogr., Sect. E 2008, 64, m1076-m1076. (m) Liang, S.-W.;
39
He, X.; Shao, M.; Li, M.-X. J. Coord. Chem. 2008, 61, 2999-3007. (n) Nie, J.; Wang, J.; Dai, C.
Acta Crystallogr., Sect. E 2010, 66, m1538-m1539. (o) Li, L.-L.; Liu, L.-L.; Zheng, A.-X.;
Chang, Y.-J.; Dai, M.; Ren, Z.-G.; Li, H.-X.; Lang, J.-P. Dalton Trans. 2010, 39, 7659-7665. (p)
Li, H.-Y.; Zhang, Y.; Ding, Y.-C.; Wang, M.; Dai, L.-X.; Lang, J.-P. J. Mol. Struct. 2011, 996,
90-94.
94) (a) Blake, A. J.; Danks, J. P.; Lippolis, V.; Parsons, S.; Schroder, M. New J. Chem. 1998, 22,
1301-1303. (b) Yu, J.-H.; Xu, J.-Q.; Yang, Q.-X.; Pan, L.-Y.; Wang, T.-G.; Lu, C.-H.; Ma, T.-H.
J. Mol. Struct. 2003, 658, 1-7. (c) Dong, F.-Y.; Li, Y.-T.; Wu, Z.-Y.; Sun, Y.-M.; Sun, W.; Liu,
Z.-Q.; Song, Y.-L. J. Inorg. Organomet. Polym. Mater. 2008, 18, 398-406. (d) Zhou, X.-P.; Lin,
S.-H.; Li, D.; Yin, Y.-G. CrystEngComm 2009, 11, 1899-1903.
95) Wang, H.; Li, M.-X.; Shao, M.; Wang, Z.-X. J. Mol. Struct. 2008, 889, 154-159.
96) Zhou, X.-P.; Li, D.; Wu, T.; Zhang, X. Dalton Trans. 2006, 2435-2443.
97) Zhang, Y.-W.; Dong, H.-Z.; Cheng, L. Acta Crystallogr., Sect. E 2008, 64, m868-m868.
98) (a) Teichert, O.; Sheldrick, W. S. Z. Anorg. Allg. Chem. 1999, 625, 1860-1865. (b) Stocker, F.
B.; Staeva, T. B.; Rienstra, C. M.; Britton, D. Inorg. Chem. 1999, 38, 984-991. (c) Teichert, O.;
Sheldrick, W. S. Z. Anorg. Allg. Chem. 2000, 626, 1509-1513. (d) Di Nicola, C.; Effendy;
Pettinari, C.; Skelton, B. W.; Somers, N.; White, A. H. Inorg. Chim. Acta 2006, 359, 53-63. (e)
Ni, W.-X.; Li, M.; Zhou, X.-P.; Li, Z.; Huang, X.-C.; Li, D. Chem. Commun. 2007, 3479-3481.
(f) Xia, J.; Zhang, Z.-J.; Shi, W.; Wei, J-F.; Cheng, P. Cryst. Growth Des. 2010, 10, 2323-2330.
(g) Su, Z.; Zhao, Z.; Zhou, B.; Cai, Q.; Zhang, Y. CrystEngComm 2011, 13, 1474-1479.
99) Chesnut, D. J.; Plewak, D.; Zubieta, J. J. Chem. Soc., Dalton Trans. 2001, 2567-2580.
40
100) (a) Hanika-Heidl, H.; Etaiw, S. E. H.; Ibrahim, M. S.; El-din, A. S. B.; Fischer, R. D. J.
Organomet. Chem. 2003, 684, 329-337. (b) Peng, R.; Li, D.; Wu, T.; Zhou, X.-P.; Ng, S. W.
Inorg. Chem. 2006, 45, 4035-4046.
101) Hibble, S. J.; Chippindale, A. M. Z. Anorg. Allg. Chem. 2005, 631, 542-545.
102) Pike, R. D.; deKrafft, K. E.; Ley, A. N.; Tronic, T. A. Chem. Commun. 2007, 3732-3734.
103) (a) Hu, M.-H.; Shen, G.-L.; Zhang, J.-X.; Yin, Y.-G.; Li, D. Cryst. Growth Des. 2009, 9,
4533-4537. (b) Etaiw, S. E. H.; Fayed, T. A.; Abdou, S. N. J. Inorg. Organomet. Polym. Mater.
2010, 20, 326-333. (c) Peng, R.; Li, M.; Dong, S.-R.; Li, Z.-Y.; Li, D. CrystEngComm 2010, 12,
3670-3675.
104) (a) Colacio, E.; Debdoubi, A.; Kivekas, R.; Rodriguez, A. Eur. J. Inorg. Chem. 2005,
2860-2868. (b) Sun, Y.-Q.; Tsang, C.-K.; Xu, Z.; Huang, G.; He, J.; Zhou, X.-P.; Zeller, M.;
Hunter, A. D. Cryst. Growth Des. 2008, 8, 1468-1470. (c) Ni, W.-X.; Li, M.; Zhan, S.-Z.; Hou,
J.-Z.; Li, D.; Inorg. Chem. 2009, 48, 1433-1441. (d) Hou, L.; Shi, W.-J.; Wang, Y.-Y.; Liu, B.;
Huang, W.-H.; Shi, Q.-Z. CrystEngComm 2010, 12, 4365-4371. (e) Wen, T.; Li, M.; Zhou, X.-
P.; Li, D. Dalton Trans. 2011, 40, 5684-5686.
105) (a) Kirfel, A. Acta Crystallogr., Sect. B 1977, 33, 2788-2790. (b) Raper, E. S.; Creighton,
J. R.; Wilson, J. D.; Clegg, W.; Milne, A. Inorg. Chim. Acta 1989, 155, 77-83. (c) Rottgers, T.;
Sheldrick, W. S. Z. Anorg. Allg. Chem. 2002, 628, 1305-1310.
106) Tanaka, D.; Masaoka, S.; Horike, S.; Furukawa, S.; Mizuno, M.; Endo, K.; Kitagawa, S.
Angew. Chem. Int. Ed. 2006, 45, 4628-4631.
107) (a) Britton, D.; Stocker, F. B.; Staeva, T. P. Acta Crystallogr., Sect. C 1999, 55, 2014-
2016. (b) Colacio, E.; Dominguez-Vera, J. M.; Lloret, F.; Sanchez, J. M. M.; Kivekas, R.;
Rodriguez, A.; Sillanpaa, R. Inorg. Chem. 2003, 42, 4209-4214. (c) Chu, D.-Q.; Wang, L.-M.;
41
Xua, J.-Q. Mendeleev Commun. 2004, 25-27. (d) Greve, J.; Nather, C. Z. Naturforsch. B 2004,
59, 1325-1331.
108) (a) Cromer, D. T.; Larson, A. C. Acta Crystallogr., Sect. B 1972, 28, 1052-1058. (b)
Kuhlman, R.; Schimek, G. L; Kolis, J. W. Polyhedron 1999, 18, 1379-1387. (c) Shi, W.-J.;
Ruan, C.-X.; Li, Z.; Li, M.; Li, D. CrystEngComm 2008, 10, 778-783. (d) Pagola, S.; Pike, R.
D.; deKrafft, K.; Tronic, T. A. Acta Crystallogr., Sect. C 2008, 64, m134-m136.
109) (a) Liang, S.-W.; Li, M.-X.; Shao, M.; He, X. J. Mol. Struct. 2008, 875, 17-21. (b) Li, Z.;
Li, M.; Zhan, S.-Z.; Huang, X.-C.; Ng, S. W.; Li, D. CrystEngComm 2008, 10, 978-980. (c) Li,
M.-X.; Miao, Z.-X.; Shao, M.; Liang, S.-W.; Zhu, S.-R. Inorg. Chem. 2008, 47, 4481-4489. (d)
Liu, C.; Ding, Y.-B.; Shi, X.-H.; Zhang, D.; Hu, M.-H.; Yin, Y.-G.; Li, D. Cryst. Growth Des.
2009, 9, 1275-1277. (e) Weng, H.-S.; Lin, J.-D.; Long, X.-F.; Li, Z.-H.; Lin, P.; Du, S.-W. J.
Solid State Chem. 2009, 182, 1408-1416.
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