Reporter: Ran-Ning Guo

Checker： Lei Shi

Date: 2012/10/09

Literature Report 5

Diazo Compounds and N-Tosylhydrazones:Novel Cross-Coupling Partners in

Transition-Metal-Catalyzed Reactions

Wang, J. et al. Acc. Chem. Res. 2012, DOI: 10.1021/ar300101k

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Contents

Can cross-coupling and metal carbene transformations bemerged into a single reaction cycle?

How many kinds of transition metals are effective in this cross-coupling reaction?

The perspective of this novel cross-coupling compared with classic ones.

Heck-Mizoroki reaction, Shapiro reaction…

Pd, Cu, Rh, Ni, Co…

Conspectus

Standard Cross-Coupling vs the Coupling Involving a Carbene Process

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Pd-Catalyzed Cross-Coupling Reaction between Benzyl Halides and TMSCHN2

Van Vranken, D. L. et al. Tetrahedron 2001, 57, 5219–5225

Ar X +SiMe3H

N2

2.5 mol% Pd2(dba)320 mol% AsPh3

2 equiv. iPr2NEtDCE, reflux

Ar

54-60%X = Cl, Br

Pd0

ArPdII

A

PdII

HTMS

Ar

H

Ar HTMS

PdII

HAr

TMSH

PdIIH

B C D

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N-tosylhydrazones have been proven to be very useful for the in situ generation of nonstabilized diazo compounds through Bamford-Stevens reaction.

N-tosylhydrazones: generate unstable diazo compounds in situ

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Pd-Catalyzed Cross-Coupling of N-Tosylhydrazones

Barluenga, J. et al. Angew. Chem. Int. Ed. 2007, 46, 5587–5590

8

Pd-Catalyzed Cross-Coupling of Vinylhalides with EDA

Wang, J. et al. J. Am. Chem. Soc. 2007, 129, 8708–8709

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The Mechanism of Pd-Catalyzed Cross-Coupling of Iodides with EDA

RI R PdII IEDA

CO2EtPdII

N2H

RCO2Et

PdIIR

H

base

PdII

N2

CO2EtR

Pd0

R

N2

CO2Et

A B D

C

Wang, J. et al. J. Am. Chem. Soc. 2007, 129, 8708–8709

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Pd-Catalyzed Oxidative Cross-Coupling between Boronic Acids and α-Diazocarbonyl Compounds

Wang, J. et al. J. Am. Chem. Soc. 2008, 130, 1566–1567

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Wang, J. et al. Chem. Commun. 2010, 46, 1724–1726

ArR'

R

NNHTs

+ Ar'B(OH)2

5 mol% Pd(PPh3)410 mol% CuCl, O2

5 equiv. LiOtBudioxane, 70 oC

Ar

Ar'

R'

R28 examples

30-84%

Pd-Catalyzed Oxidative Cross-Coupling between Boronic Acids and N-Tosylhydrazones

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Pd-Catalyzed Cross-Coupling between Benzylhalides and N-Tosylhydrazones

Wang, J. et al. Org. Lett. 2009, 11, 4732–4735

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Pd-Catalyzed Cross-Coupling between Benzylhalides and Diazo Compounds

Van Vranken, D. L. et al. Tetrahedron 2005, 61, 6438–6441

Yu, W.-Y. et al. Org. Lett. 2009, 11, 469–472

BrR

N2

OEt

O

iPrNEt2, C6H680 oC, 12 h

R CO2Et

up to 74% yield

Ar1 Br

CO2Me

N2

Ar2 CO2Me

Ar2Ar1

Pd2(dba)3 CHCl3PPh3

Na2CO380 oC, 3 h

Pd2(dba)3 CHCl3AsPh3

E/Z ratio >20:1up to 88% yield

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Pd-Catalyzed Cross-Coupling of Diazo Compounds with Allylhalides

Wang, J. et al. Chem. Commun. 2008, 4198–4200

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Pd-Catalyzed Oxidative Cross-Coupling of N-Tosylhydrazones with Terminal Alkynes

Wang, J. et al. Angew. Chem. Int. Ed. 2011, 50, 3510–3514

R'O2CR

N2+ R''

5 mol% Pd(OAc)220 mol% P(2-furyl)3

BQ, iPr2NHPhMe, 80 oC

R'O2C

R''

R

27-71%E:Z >20:1

R

NNHTs

R' + H R''

5 mol% Pd(OAc)220 mol% P(2-furyl)3

BQ, LiOtBu1,4-dioxane, 90 oC

R''

RR'

R

PdII

R'

R''

RR'

PdII

R''

42-83%Z:E >20:1

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Liang, Y.-M. et al. Chem. Eur. J. 2011, 17, 6918–6921

Migratory Insertion Allenyl Group in Pd-Catalyzed Reaction

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Migratory Insertion Cyclopropyl Group in Pd-Catalyzed Reaction

Wang, J. et al. Org. Lett. 2012, 14, 922–925

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Migratory insertion/β-hydroxy elimination sequence in Pd-Catalyzed Reaction

Wang, J. et al. Chem. Commun. 2011, 47, 3622–3624

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β-Hydrogen Elimination vs Transmetalation

In the catalytic cycle of the cross-coupling reactions described above, the alkyl palladium species, which are formed by migratory insertion, typically undergo β-hydrogen elimination to give rise to the final products with the formation of C=C. However, when the β-hydrogens are not available, it may be possible to undergo a cascade process, such as a transmetalation with an organometallic reagent and subsequent reductive elimination to form two separate C-C in a carbenic center.

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Pd-Catalyzed Three-Component Cross-Coupling Reaction

Wang, J. et al. J. Am. Chem. Soc. 2010, 132, 13590-23591

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Pd-Catalyzed Decarboxylation/Migratory Insertion/Reductive Elimination Cascade

Liang, Y.-M. et al. Angew. Chem. Int. Ed. 2012, 51, 1370-1374

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Pd-Catalyzed Carbonylation/Acyl Migratory Insertion Cascade

ArI + R CO2R'

N2

+ Et3SiH

5 mol% Pd(PPh3)42 equiv. Et3N

CO balloonDCE, 60 oC

Ar

O

CO2R'

R

18 examples43-88%

ArPdIICO

Ar PdII

OAr PdII

O

CO2R'R

O

Ar

CO2R'

PdII

R

Et3SiH

Wang, J. et al. Angew. Chem. Int. Ed. 2010, 49, 1139-1142

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Pd-Catalyzed Carbonylation Staudinger Cycloaddition: β-Lactam Synthesis

Wang, J. et al. J. Am. Chem. Soc. 2011, 133, 4330–4341ACS Catal. 2011, 1, 1621–1630

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Pd-Catalyzed Amidation of N-Tosylhydrazones with Isocyanides

NNHTs

Pd0 Pd

N

tBu

C N

tBu

NHtBu

OC N tBu

2 mol% Pd(PPh3)4Cs2CO3

1,4-dioxane-H2O75%

C N tBu

H2O

Ding, K. et al. Chem. Eur. J. 2011, 17, 12268–12271

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Cu(I)-Catalyzed Coupling of N-Tosylhydrazones with Terminal Alkynes

Wang, J. et al. Angew. Chem. Int. Ed. 2011, 50, 1114–1117

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Cu-Catalyzed Synthesis of Benzofurans, Indoles, and Phenanthrenes

NNHTs

HAr+

H R

cat. CuI

baseAr

H R

H

Ar =

XH

Ar =

Ph

CuI

R

XH X R

X = O or NH

R R

Wang, J. et al. Org. Lett. 2011, 13, 5020-5023

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The sequence of migratory insertion/protonation from Cu(I) carbene, provides a new possibility for C(sp2)-C(sp3) and C(sp)-C(sp3) single bond formation.

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Cu-Catalyzed C(sp)-C(sp3) Bond Formation

Wang, J. et al. J. Am. Chem. Soc. 2012, 134, 5742–5745

Cu(I)-Catalyzed Direct Benzylation or Allylation of 1,3-Azoles with N-Tosylhydrazones

N

XH +

NNHTs

R 10 mol% CuI

LiOtBuPhMe or dioxane

110 oC, 1.5 h

N

X

R

X = N, S

48-86%

Wang, J. et al. J. Am. Chem. Soc. 2011, 133, 3296-3299

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30

Rh(I)-Catalyzed One-Pot Three-Component Reaction

Yu, W.-Y. et al. Org. Lett. 2011, 13, 5370-5373

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Ni- and Co-Catalyzed Reaction

O

NMe

H +

NNHTs

NiBr2/Phen(10 mol%)

LiOtBu1,4-dioxane100 oC, 8 h

O

NMe

86%

N

OPh H+

NNHTs

LiOtBu1,4-dioxane120 oC, 7 h

CoBr2/Phen(10 mol%)N

OPh

71%

Miura, M. et al. Angew. Chem. Int. Ed. 2012, 51, 775-779

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Summary-Comparison of Migratory Insertions

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Summary-Cross-Coupling with Carbonyl: Triflate Approach vs N-Tosylhydrazone Approach

RO

R'

ROTf

R'

cat. Pd0

ArM

RAr

R'

cat. Pd0

ArX

RNNHTs

R'

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Summary-Alkene Synthesis : Shapiro Reaction vs Pd-Catalyzed Cross-Coupling

R'

R R''

NNHTs

nBuLi

R'

R R''

Shapiro reaction

E

R'

R R''

E

E = H, O

LiOtBu or Cs2CO3

R'

R R''

N2

XPdII-E

R'

R R''

PdII E R'

R R''

PdIIE

R'

R R''

E

E = Ar, vinyl, alkynyl, allyl…

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Summary-Deoxygenative Transformation of Carbonyl Group into C-C or C=C Bonds

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Thanks!