sébastien goudreau

1

Sébastien Goudreau

Literature meeting : 13-02-2007

Rhodium(I) ChemistryRhodium(I) Chemistry

Rhodium(I)

2

RhodiumRhodium

• Number 45

• [Kr]4d85s1

• Hard silvery white and durable metal that has a high reflectance.(Use in jewellery)

• Does not form an oxide, is not attacked by acids.

• Very high melting point : 2236°C

• It is the most expensive precious metal.

http://en.wikipedia.org/wiki/Rhodium

3

ApplicationsApplications

• The primary use of this element is as an alloying agent for hardening platinum and palladium.

• It is used as an electrical contact material due to its low electrical resistance, low and stable contact resistance, and its high corrosion resistance.

• Plated rhodium, made by electroplating or evaporation, is extremely hard and is used for optical instruments.

• This metal finds use in jewelry and for decorations.

• It is also a highly useful catalyst.

http://en.wikipedia.org/wiki/Rhodium

4

HistoryHistory

• Rhodium was discovered in 1803 by William Hyde Wollaston soon after his discovery of palladium.

• Wollaston made this discovery in England using crude platinum ore that he presumably obtained from South America.

• His procedure involved dissolving the ore in aqua regia (HCl + HNO3), neutralizing the acid with NaOH.

• He then precipitated the platinum metal by adding NH4Cl, as ammonium chloroplatinate.

• The element palladium was removed as palladium cyanide after treating the solution with mercuric cyanide.

• The material that remained was a red rhodium(III) choride. (Greek rhodon meaning "Rose")

• Wilkinson’s catalyst : RhCl(PPh3)3 : 1965

William Hyde Wollaston

Geoffrey WilkinsonNobel Prize 1973

Wilkinson et al. J. Org. Chen. Chem. Commun., 1965, 7, 131.http://en.wikipedia.org/wiki/Rhodium

5

Rhodium(I) in Organic ChemistryRhodium(I) in Organic Chemistry

1) C-H and C-C bond activation

2) HydrorhodationA) HydrogenationB) HydroarylationC) HydroalkynationD) HydroacylationE) HydrosilylationF) Hydroboration

3) AdditionA) 1,4 additionB) 1,2 additionC) Coupling

4) Sigmatropic RearrangementA) CycloadditionB) Alder-ene

5) -Allyl chemistry

6)-aryl elimination

Square plane

RhX

L

L

16e-L

I

6

1) C-H and C-C bond activation1) C-H and C-C bond activation

(a) Milstein et al. Angew. Chem. Int. Ed. 2007, 46, ASAP. (b) Bergman et al. J. Am. Chem. Soc. 2006, 128, 2452. (c) Milstein et al. J. Am. Chem. Soc. 2003, 125, 11041.

Prof. David MilsteinThe Weizmann

Institute of Science, Israel

RhLnR' R

Y

LnRhY

R

R'oxydative addition

in C-C bond+

IIII

RhLnLnRh

CH3oxydative addition

in C-C bond+

IIII

H3C

XX

RhLnH R

Y

LnRhY

R

Hoxydative addition

in C-H bond+

IIII

RhLnLnRh

Hoxydative addition

in C-H bond+

IIII

X X

RhLn LnRh

Hoxydative additionin C-H bond

+I IIIH

RR

[1,3]LnRh C

IIIR

vinylydene

RhLnLnRh

R

Hoxydative addition

in C-H bond+

IIIIH Rsp3

sp2

sp

7

2) Hydrorhodation2) Hydrorhodation

A) Hydrogenation

B) Hydroarylation

C) Hydroalkynation

D) Hydroacylation

E) Hydrosilylation

F) Hydroboration

RhX

LL

L

Rh

X

L

LZ

H

Rh

X

LL

ZH

Rh

X

LL

Z

Y

RH

YR

H

ZH ZI

III

IIIIII

18e-

18e-

16e-

16e-

R

Y

R

YR

Y

+ H ZY

RH

Z

RhXL3

Z-H activation

oxydative addition

hydrorhodation

migration

reductiveelimination

L

L

8

A) HydrogenationA) Hydrogenation

Zassinovich, Mestroni Chem. Rev. 1992, 92, 1051 and references cited therein

Rh ClPh3PPh3P

Rh

Cl

Ph3P

Ph3PH

H

Rh

X

Ph3PPh3P

HH

Rh

X

Ph3PPh3P

H

Y

RH

YR

H

HH HI

III

III

18e-

16e-

16e-

14e-

R

Y

R

YR

Y

+ H HY

RH

H

H-H activation

oxydative addition

hydrorhodation

migration

reductiveelimination

RhCl(PPh3)3

III

9

Enantioselective HydrogenationEnantioselective Hydrogenation

CO2Me

N(H)CBz

R CO2Me

N(H)CBz

R

P

P

iPr

iPr

iPr

iPr

[(COD]RhiPrDuPHOS]OTf

iPrDuPHOS

H2 (2 atm), MeOH, rt

CO2Me

N(H)CBzF

CO2Me

N(H)CBz

CO2Me

N(H)CBz

>99% ee 99.4% ee 99.5% ee

Burk et al. J. Am. Chem. Soc. 1993, 115, 10125.

10

B) HydroarylationB) Hydroarylation

RhX

LL

L

Rh

X

L

LAr

H

Rh

X

LL

ArH

Rh

X

LL

ArR

H

RH

ArH ArI

III

III

III

18e-

18e-

16e-

16e-

R

R

R

+ H Ar RH

Ar

RhXL3

C-H activationoxydative addition

hydrorhodation

migration

reductiveelimination

L

L

Pfeffer et al. Chem. Rev. 2002, 102, 1731.

11

B) Hydroarylation : exempleB) Hydroarylation : exemple

Pfeffer et al. Chem. Rev. 2002, 102, 1731.

12

B) Hydroarylation : exempleB) Hydroarylation : exemple

Pfeffer et al. Chem. Rev. 2002, 102, 1731.

13

C) HydroalkynationC) Hydroalkynation

RhX

LL

L

Rh

X

L

L H

Rh

X

LL H

Rh

X

LL

RH

RH

HI

III

III

III

18e-

18e-

16e-

16e-

R

R

R

+ H RHRhXL3

C-H activationoxydative addition

hydrorhodation

migration

reductiveelimination

L

L

Pfeffer et al. Chem. Rev. 2002, 102, 1731.

14

C) Hydroalkynation : exemplesC) Hydroalkynation : exemples

Pfeffer et al. Chem. Rev. 2002, 102, 1731.

15

D) HydroacylationD) Hydroacylation

RhX

LL

L

Rh

X

L

L H

Rh

X

LL H

Rh

X

LL

RH

R

H

HI

III

III

III

18e-

18e-

16e-

16e-

R

R

R

+RhXL3

C-H activationoxydative addition

hydrorhodation

migration

reductiveelimination

L

L

R'

Y

YR'

YR'

YR'

Y

R'

R

HY

R'H R'

Y

Pfeffer et al. Chem. Rev. 2002, 102, 1731.

16

D) Hydroacylation : exemplesD) Hydroacylation : exemples

Pfeffer et al. Chem. Rev. 2002, 102, 1731.

17

D) Hydroacylation : exampleD) Hydroacylation : example

Pfeffer et al. Chem. Rev. 2002, 102, 1731.

18

Intramolecular HydroacylationIntramolecular Hydroacylation

Pfeffer et al. Chem. Rev. 2002, 102, 1731.

19

C) HydrosilylationC) Hydrosilylation

RhX

LL

L

Rh

X

L

LSiR'3

H

Rh

X

LL

SiR'3H

Rh

X

LL

SiR'3

Y

RH

YR

H

R'3SiH SiR'3I

III

IIIIII

18e-

18e-

16e-

16e-

R

Y

R

YR

Y

+ H SiR'3Y

RH

R'3Si

RhXL3

Si-H activation

oxydative addition

hydrorhodation

migration

reductiveelimination

L

L

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C) HydrosilylationC) Hydrosilylation

R1 R2

O

Si HR'R

R'' R1 R2

OSi

R

R''R'

R1 R2

OHH3O+cat

+

R1 R2

N

Si HR'R

R'' R1 R2

NSi

R

R''R'

R1 R2

NHH3O+cat

+

R3

R3R3

R1 R2

Si HR'R

R''

OSi

R

R''R'

H3O+cat+

O

X

X

R1 R2

H

O

X

R1 R2

H

Eor E+

R1 R2 Si HR'R

R'' R1 R2

Si

R

R''R'

cat+

R1Si HR'

R

R'' R1

Si

R

R''R'

cat+

Pfeffer et al. Chem. Rev. 2002, 102, 1731.

21

D) HydroborationD) Hydroboration

Guiry et al. Adv. Synth. Catal. 2005, 347, 609.

RhX

LL

L

Rh

X

L

LB

H

Rh

X

LL H

Rh

X

LL

BR

H

H BI

III

III

III

18e-

18e-

16e-

16e-

R

R

R

+ RH

B

RhXL3

Si-H activation

oxydative addition

hydrorhodation

migration

reductiveelimination

L

L

O

O

OO

BOO

OO

H BO

OO

OR

B

H

OO

+

Rh

X

LL

BH

III

16e-

OO

R

or

RH

BO

ORB

H

OO +

22

D) HydroborationD) Hydroboration

Guiry et al. Adv. Synth. Catal. 2005, 347, 609.

23

Hydrorhodation : ConclusionHydrorhodation : Conclusion

• Atom efficient

• Mild conditions

• Good alternative route

• Regioselectivity : can be problematic

• Enantioselectivity : can be very good

24

2) Addition reaction2) Addition reaction

A) 1,4 addition

B) 1,2 addition

C) Coupling

Y

X

R M

RhLn

Y

X

R' R

R'

R' Y

X

R M

RhLn

RY

X

R'

25

A) 1,4 addition reactionA) 1,4 addition reaction

M : Organoboron (organostannate, organosilane, organobismuth)R : Aryl

Fagnou, Lautens Chem. Rev. 2003, 103, 169.

Y

X

R M

RhLn

Y

X

R' R

R'

26

A) 1,4 Addition : exemplesA) 1,4 Addition : exemples

Fagnou, Lautens Chem. Rev. 2003, 103, 169.

27

A) 1,4 Addition : examplesA) 1,4 Addition : examples

Fagnou, Lautens Chem. Rev. 2003, 103, 169.

28

A) 1,4 Addition : examplesA) 1,4 Addition : examples

Fagnou, Lautens Chem. Rev. 2003, 103, 169.

29

A) 1,4 Addition : examplesA) 1,4 Addition : examples

Fagnou, Lautens Chem. Rev. 2003, 103, 169.

30

Fagnou, Lautens Chem. Rev. 2003, 103, 169.

A) 1,4 Addition : examplesA) 1,4 Addition : examples

31

Krische’s chemistryKrische’s chemistry

32

Krische’s chemistryKrische’s chemistry

Krische et al. J. Am. Chem. Soc. 2002, 124, 15156.

33

B) 1,2 Addition reactionB) 1,2 Addition reaction

Fagnou, Lautens Chem. Rev. 2003, 103, 169.

M : Organoboron (organostannate, organosilane, organobismuth)R : Aryl

R' Y

X

R M

RhLn

RY

X

R'

34

B) 1,2 Addition : exemplesB) 1,2 Addition : exemples

Fagnou, Lautens Chem. Rev. 2003, 103, 169.

35

Ellman et al. J. Am. Chem. Soc. 2005, 127, 1092.

B) 1,2 Addition : exemplesB) 1,2 Addition : exemples

36

(a) Fagnou, Lautens Chem. Rev. 2003, 103, 169. (b) Iwasawa et al. J. Am. Chem. Soc. 2006, 128, 8706.

B) 1,2 Addition : exemplesB) 1,2 Addition : exemples

37

Krische’s chemistryKrische’s chemistry

Krische et al. J. Am. Chem. Soc. 2006, 128, 718.

38

C) CouplingC) Coupling

Fagnou, Lautens Chem. Rev. 2003, 103, 169.

39

Addition reaction : ConclusionAddition reaction : Conclusion

• Mild conditions : presence of water

• Good enantioselectivity

• Excess of organoboron needed

40

4) Sigmatropic rearrangement4) Sigmatropic rearrangement

A) Cycloaddition

B) Alder-ene

2+2+22+2+1 (Pauson-Khand)3+24+25+26+14+2+2

Paul A. WenderStanford University, USA

H HAlder-ene

41

Mecanism : [2+2+2]Mecanism : [2+2+2]

R3

R4

R1

R2

oxydativecoupling

RhLn RhLn

I IIIR1

R2

R4R3

RhLn

IIIR1

R2

R4R3

R5

R6 RhLn

R6R5

R2

R1

R3 R4

insertion

R2

R5

R6

R4R3

R1

reductiveelimination

III

RhLn+I

RhLn

R6R5

R2

R1

R3 R4

III

R7

R8

reductiveelimination

R1

R3 R4

R2

RhLn+I

R3

R4

R1

R2R7

R8

RhLn

IR2

R5

R6

R4R3

R1

Lautens et al. Chem. Rev. 1996, 96, 49.

42

[2+2+1] Cycloaddition : Pauson-Khand Reaction[2+2+1] Cycloaddition : Pauson-Khand Reaction

R oxydativecoupling

RhLn RhLnI III

RhLn

III

R

C insertion

reductiveelimination

III

RhLn

+I

reductiveelimination

RhLn+I

RhLn

I

X X

H

R

R

X

RhLn

X

R

H

-hydride

reductiveelimination

X

R

RhLn+I

OCO

X

H

RhLnX

H

R

O

IIIRhLnX

H

R

O

R

X

H

O

or

R

X

R

X

H

O

X

CO+

Lautens et al. Chem. Rev. 1996, 96, 49.

43

[2+2+1] Cycloaddition : Pauson-Khand Reaction[2+2+1] Cycloaddition : Pauson-Khand Reaction

Jeong et al. J. Am. Chem. Soc. 2000, 122, 6771.

44

[3+2] Cycloaddition[3+2] Cycloaddition

RhLn

I

Ph R

O

Ph Ph

O

Ph Ph

RPh

Ph

R

oxydativecoupling

RhLn RhLn

I III

RPh

Ph

R

reductiveelimination

Ph

Ph R

Ph

RhLn+I

O

PhPh

OPh

Ph

O

RhLn

III

RPh

OPh

Ph

O

Ph Ph

RPh

[2,2]

Wender et al. J. am. Chem. Soc. 2006, 128, 14814.

45

[4+2] Cycloaddition : Diels Alder[4+2] Cycloaddition : Diels Alder

Mikami et al. J. Am. Chem. Soc. 2006, 128, 12648.

oxydativecoupling

RhLn RhLn

I III

reductiveelimination

RhLn +I

RhLn

I

X

R1

X

R1

X

R2

R1

RhLn

RhLn

III

X

R1

R2

X

R1

R2

III

R2

X

R2

X

R1

R2

46

[5+2] Cycloaddition[5+2] Cycloaddition

Saito et al. J. Org. Chem. 2006, 71, 6437.

47

[6+1] cycloaddition[6+1] cycloaddition

Wender et al. Angew. Chem. Int. Ed. 2006, 45, 3957.

48

[4+2+2] and [2+2+2+1] cycloaddition[4+2+2] and [2+2+2+1] cycloaddition

Ojima et al. Org. Lett. 2004, 6, 3589.Wender et al. J. Am. Chem. Soc. 2006, 128, 5354.

49

B) Alder-eneB) Alder-ene

Zhang et al. J. Am. Chem. Soc. 2002, 124, 8198.

Ph oxydativecoupling

RhLn RhLnI III

reductiveelimination

RhLn+I

RhLn

I

O O

Ph-hydride

O

H

O

RhLn

IIIO

PhO

H O

O

Ph

O O OO

Ph

PhH H

Alder-ene

H

H

50

ConclusionConclusion

• Access to a large variety of cycles

• Regioselectivity : need linkers

51

5) Allylic5) Allylic

R

O

O

MeO

Rh

R- MeOCOO-

Nu

RhLnI

IIIR

NuRhLnI

-

(a) P.A. Evans et al. J. Am. Chem. Soc. 2004, 126, 8642. (b) P.A. Evans et al. J. Am. Chem. Soc. 2003, 125, 8974. (c) P.A. Evans et al. J. Am. Chem. Soc. 2002, 124, 7882.

52

6) 6) -aryl elimination-aryl elimination

John F. HartwigYale University, USA

53

ConclusionConclusion

1) C-H and C-C bond activation

2) HydrorhodationA) HydrogenationB) HydroarylationC) HydroalkynationD) HydroacylationE) HydrosilylationF) Hydroboration

3) AdditionA) 1,4 additionB) 1,2 additionC) Coupling

4) Sigmatropic RearrangementA) CycloadditionB) Alder-ene

5) -Allyl chemistry

6)-aryl elimination

Square plane

RhX

L

L

16e-L

I

54

ConclusionConclusion