Cooperativity in Asymmetric Bimetallic

Catalysis05/20/2015

Presented By Michael C. Young

Strategies for Bimetallic Catalysis•There are numerous intramolecular and intermolecular methods to achieve bi-metallic catalysis:

Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.

Pioneering Work•Allylation of activated methylene compounds had originally been difficult to achieve good ee with chiral phosphine ligands.

Hayashi, T.; Kanehira, K.; Tsuchiya, H.; Kumada, M. Chem. Commun., 1982, 2586.

i) NaH/THF; ii) allylacetate/[(allyl)PdCl]2 / -30 ºC

80%, 45% ee (S) 64%, 31% ee (S) 86%, 15% ee (S)

Improved Allylation Protocol (I)•Kumada group investigated improving the ee with a new class of chiral phosphine.

Hayashi, T.; Kanehira, K.; Hagihara, T.; Kumada, M. J. Org. Chem., 1988, 113.

Fe

PPh2

PPh2

R

R=

NOH

NH

OH

NOH

OH

NOH

OH

O ONaH

THF THF

OAc

[(allyl)PdCl]2

O O

-50 ºC

N

73% (S)

62% (S)

62% (S)

53% (S)

69% (S)

HO2C

OH

Fe

PPh2

PPh2

N

O ONaH

THF THF

OAc

[(allyl)PdCl]2

O O

OHL

L

OO OO OO

O O O O

H

O

Ph

O

OEt

O

OMe

OO

86%, < 5 % ee 75%, ee nd 86%, 58% ee

74%, 55% ee 93%, 51% ee

88%, 47% ee (R) 70%, 22% ee 82%, 3% ee (R)

Improved Allylation Protocol (II)•Replacing H-bonding with metal chelation changes solvent preference as well as stereoselectivity.

Sawamura, M.; Nagata, H.; Sakamoto, H.; Ito, Y. J. Am. Chem. Soc., 1992, 194, 2586.

OO

86%, < 5 % ee

Fe

PPh2

PPh2

N

NaH

THF THF

OAc

[(allyl)PdCl]2

OHL

L

OO

Fe

PPh2

PPh2

N

O

OO

ONO

Fe

PPh2

PPh2

N

O

ON

ONO

L1 L2

Mesitylene

OAc

Pd2dba3 · CHCl3

L / KF

O O

-25 ºC / 40 h

O O

L1: 92%, 60% ee (R)L2: 90%, 70% ee (R)

Bifunctional Asymmetric Nitro Allylation•Ito and coworkers hoped that they could better understand their catalyst in another transformation.

Sawamura, M.; Nakayama, Y.; Tang, W.-M.; Ito, Y. J. Org. Chem., 1996, 61, 9090.

OAc

Pd2dba3 · CHCl3

L1 / MF

O2N

O

-25 ºC / 40 h

O2N

O

Base Solvent Conc. Yield (%) ee %

KF Mesitylene 1.0 M 40 14 (R)

KF Toluene 1.0 M 47 19 (R)

KF THF 1.0 M 66 25 (R)

KF CH2Cl2 1.0 M 33 25 (R)

RbF THF 1.0 M 50 29 (R)

RbF CH2Cl2 1.0 M 57 38 (R)

RbF CH2Cl2 0.5 M 28 42 (R)

CsF CH2Cl2 1.0 M 31 31 (R)

Fe

PPh2

PPh2

N

O

OO

ONO

L1

OAc

Pd2dba3 · CHCl3

L1 / MF

O2NOR

O

-25 ºC / 40 h

O2NOR

O

Base R-Group Add. Yield (%) ee %

KF Me N/A 43 23 (R)

KF Et N/A 44 37 (R)

KF t-Bu N/A 95 51 (R)

RbF t-Bu N/A 95 60 (R)

CsF t-Bu N/A 91 34 (R)

RbF t-Bu RbClO4 98 69 (R)

RbF t-Bu RbClO4* 92 80 (R)

Trost Ligand as a Bifunctional Ligand

Trost, B. M.; Radinov, R. J. Am. Chem. Soc., 1997, 199, 2586.

HNNHO O

PAr2 Ar2P

OAc

0.25%

NaO2SPh

H2O / DCM

2 h / 0 ºCO2SPh

0.25% [(allyl)PdCl]2

91 % (98% ee)

Ar =O

O O

5% [(allyl)PdCl]2

HNNHO O

PPh2 Ph2P

OAc

5%

NaO2SPh

H2O / DCM / Bu4NBr

18 h (yield/ee not discussed)

O2SPh

0.13% [(allyl)PdCl]2

HNNHO O

PPh2 Ar2P

OAc

0.3 %

MO2SPh

H2O / DCM / 0 ºC O2SPh

Asymmetric Carbonyl Alkylation (I)

Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.Kitamura, M.; Suga, S.; Kawai, K.; Noyori, R. J. Am. Chem. Soc., 1986, 108, 6072.

R CHO

NMe2

OH2%

1.2 eq R'2Zn

R

R' OH

H

Aldehyde Zinc Solvent Time (h) Yield (%) ee (%) – (S)

C6H5 (C2H5)2Zn PhMe 6 97 98

C6H5 (C2H5)2Zn Hexanes-PhMe 6 94 98

C6H5 (C2H5)2Zn Et2O-PhMe 6 98 99

C6H5 (C2H5)2Zn THF-PhMe 64 44 91

C6H5 (CH3)2Zn PhMe 70 59 91

P-ClC6H4 (C2H5)2Zn PhMe 12 86 93

(E)-C6H5CHCH (C2H5)2Zn PhMe 6 81 96

C6H5CH2CH2 (C2H5)2Zn PhMe 12 80 90

N-C6H13 (C2H5)2Zn PhMe 24 81 61

Asymmetric Carbonyl Alkylation (II)

Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.DiMauro, E. F.; Kozlowski, M. C. Org. Lett., 2001, 3, 3053.

Asymmetric Carbonyl Alkylation (III)

Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.Funabashi, K.; Jachmann, M.; Kanai, M.; Shibasaki, M. Angew. Chem., Int. Ed., 2003, 42, 5489.

Shibasaki-BINOL Chemistry

Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.Shibasaki, M.; Kanai, M.; Matsunaga, S.; Kumagai, N. Acc. Chem. Res., 2009, 42, 1117.Sasai, H.; Suzuki, T.; Arai, S.; Arai, T.; Shibasaki, M. J. Am. Chem. Soc., 1992, 114, 4418.Arai, T.; Sasai, H.; Aoe, K.-I.; Okamura, K.; Date, T.; Shibasaki, M. Angew. Chem., Int. Ed., 1996, 35, 104.

Asymmetric Strecker-Type Reactions

Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.Masumoto, S.; Usuda, H.; Suzuki, M.; Kanai, M.; Shibasaki, M. J. Am. Chem. Soc., 2003, 125, 5634.Kanai, M.; Kato, N.; Ichikawa, E.; Shibasaki, M. Synlett, 2005, 1491.Kato, N. et al. J. Am. Chem. Soc., 2006, 128, 16438.

Catalytic Asymmetric Aldol Reactions

Trost, B. M.; Ito, H. J. Am. Chem. Soc., 2000, 122, 12003.

Diol Desymmetrization

Trost, B. M.; Mino, T. J. Am. Chem. Soc., 2003, 125, 2410.

1,2-Alkynylation of Aldehydes

Trost, B. M.; Weiss, A. H.; von Wangelin, A. J. J. Am. Chem. Soc., 2006, 128, 8.

Tetrametallic Catalysis

Endo, K.; Ogawa, M.; Shibata, T. Angew. Chem., Int. Ed., 2010, 49, 2410.

Bimetallic Salen Complexes (I)

Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931. Keller, F.; Rippert, A. J. Helv. Chim. Acta, 1999, 82, 125.DiMauro, E. F>; Kozlowski, M. C. Org. Lett., 2001, 3, 1641.Chen, Z.; Furutachi, M.; Kato, Y.; Matsunaga, S.; Shibasaki, M. J. Am. Chem. Soc., 2008, 130, 2170.Handa, S.; Gnanadesikan, V.; Matsunaga, S.; Shibasaki, M. J. Am. Chem. Soc., 2007, 129, 4900.

Bimetallic Salen Complexes (II)

Handa, S.; Nagawa, K.; Sohtome, Y.; Matsunaga, S.; Shibasaki, M. Angew. Chem., Int. Ed., 2008, 47, 3230.

Bimetallic Catalysis for BINOL Synthesis

Gao, J.; Reibenspies, J. H.; Martell, A. E. Angew. Chem., Int Ed., 2003, 42, 6008.

R

N N

N N

R

O

OCu Cu

R

N N

N N

R

O

OCu Cu

H

H

H

H

R: 1a = H 1b = Me 1c = tBu

R: 3a = H 3b = Me 3c = tBu

R

N N

N N

R

Ph

PhPh

Ph

O

OCu Cu

R

N N

N N

R

Ph

PhPh

Ph

O

OCu Cu

H

H

H

H

1d 3d

Bimetallic Hetereogeneous Catalyst

Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.Nitabaru, T.; Kumagai, N.; Shibasaki, M. Tetrahedron Lett., 2008, 49, 272.Nitabaru, T.; Nojiri, A.; Kobayashi, M.; Kumagai, N.; Shibasaki, M. J. Am. Chem. Soc., 2009, 131, 13860.

“Robot-like” Bimetallic Pd Catalyst

Jauntze, S.; Peters, R. Angew. Chem., Int Ed., 2008, 47, 9284.Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.

Separate Metal Centers

Sawamura, M.; Sudoh, M.; Ito, Y. J. Am. Chem. Soc., 1996, 118, 3309.

Jacobsen Catalyst (I)

Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.Martìnez, L. E.; Leighton, J. L.; Carsten, D. H.; Jacobsen, E. N. J. Am. Chem. Soc., 1995, 117, 5897.

Jacobsen Catalyst (II)

Tokunaga, M.; Larrow, J. F.; Kakiuchi, F.; Jacobsen, E. N. Science, 1997, 277, 936.Nielsen, L. P. C.; Stevenson, C. P.; Jacobsen, E. N. J. Am. Chem. Soc., 2004, 126, 1360.Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.

Jacobsen Catalyst (III)

Sammis, G. M.; Jacobsen, E. N. J. Am. Chem. Soc., 2003, 125, 4442.Sammis, G. M.; Danjo, H.; Jacobsen, E. N. J. Am. Chem. Soc., 2004, 126, 9928.

Bimetallic Epoxide Fluoridation

Kalow, J. A.; Doyle, A. G. J. Am. Chem. Soc., 2010, 132, 3268.Kalow, J. A.; Doyle, A. G. J. Am. Chem. Soc., 2011, 133, 16001.Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.

Bridged Bimetallic Catalysts

Belekon’, Y. N.; et al. J. Am. Chem. Soc., 1999, 121, 3968.Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.

CO2 Activation With Bimetallic Complexes

Clegg, W.; Harrington, R. W.; North, M.; Pasquale, R. Chem. Eur. J., 2010, 16, 6828.North, M.; Quek, S. C. Z.; Pridmore, N. E.; Whitwood, A. C.; Wu, X. ACS Cat., 2015, 5, 3398.

Zr-Epoxide Azidination

Nugent, W. A. J. Am. Chem. Soc., 1992, 114, 2768.Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.

Tethered Bimetallic Catalysis

Konsler, R. G.; Karl, J.; Jacobsen, E. N. J. Am. Chem. Soc, 1998, 120, 10780.

The Winner!

Al Together

Mazet, C.; Jacobsen, E. N. Angew. Chem., Int. Ed., 2008, 47, 1762.

Resolution/Polymerization

Thomas, R. M.; et al. J. Am. Chem. Soc., 2010, 132, 16520.

Vanadium Oxidation of Naphthol

Guo, Q.-X.; Gong, L.-Z.; et al. J. Am. Chem. Soc., 2007, 129, 13927.

Tethered and Bridged Ti-Salen

Zhang, Z.; Wang, Z.; Zhang, R.; Ding, K. Angew. Chem., Int. Ed., 2010, 49, 6746.

Oligomeric/Polymeric Scaffolds

Breinbauer, R.; Jacobsen, E. N. Angew. Chem., Int. Ed., 2000, 39, 3604.Annis, D. A.; Jacobsen, E. N. J. Am. Chem. Soc., 1999, 121, 4147.Rossbach, B. M.; Leopold, K.; Weberskirch, R. Angew. Chem., Int. Ed., 2006, 45, 1309.Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.

Coordination Tethered/Controlled Catalyst

Gianneschi, N. C.; Bertin, P. A.; Nguyen, S. T.; Mirkin, C. A>; Zakharov, L. N.; Rheingold, A. L. J. Am. Chem. Soc., 2003, 125, 10508.

Hydrogen Bond Tethered Catalysts

Park, J.; Lang, K.; Abboud, K. A.; Hong, S. Chem.-Eur. J., 2011, 17, 2236.Park, J.; Lang, K.; Abboud, K. A.; Hong, S. J. Am. Chem. Soc., 2008, 130, 16484.Park, J. Hong, S. Chem. Soc. Rev., 2012, 41, 6931.

Nanocage Embedded Catalysts

Yang, H.; Zhang, L.; Zhong, L.; Yang, Q.; Li, C. Angew. Chem., Int. Ed., 2007, 46, 6861.

OOH

OHO

Thank you for your attention!

http://debbieohi.com/blather2009/?currentPage=6, Accessed 05/20/2015.

Question 1

Endo, K.; Ogawa, M.; Shibata, T. Angew. Chem., Int. Ed., 2010, 49, 2410.

•Catalyst L1 is effective in asymmetric alkylation of enones in the presence of Cu(II) and Zn(II), while L2 shows very low reactivity and enantioinduction. Provide two structures that are likely obtained in equilibrium upon treatment of L2 with Cu(II) and Zn(II) that would explain the poor selectivity (Hint, think about the solubility).

Question 2

Handa, S.; Nagawa, K.; Sohtome, Y.; Matsunaga, S.; Shibasaki, M. Angew. Chem., Int. Ed., 2008, 47, 3230.

•Shibasaki showed that a Cu:Sm complex with tetrahydroxy Salen 1 gave syn products from a nitro Mannich reaction, while most Henry reactions catalyzed prefer to give anti products. For example, the same ligand complexed with Pd and La was found to give anti products with good selectivity. Contrast the transition states to explain this difference in selectivity.

Cu/Sm/1

Question 3

Sawamura, M.; Sudoh, M.; Ito, Y. J. Am. Chem. Soc., 1996, 118, 3309.

•Ito and coworkers demonstrated that a mixture of Pd(S,S)-(R,R)-TRAP and Rh(S,S)-(R,R)-TRAP gave good enantioselectivity for the asymmetric allylation of α-cyanoesters. Although the reaction did not proceed without palladium, in the presence of only Pd(S,S)-(R,R)-TRAP the reaction gave a comparable yield, albeit with no enantioselectivity. Draw the mechanism of the reaction without Rh (remember that the Pd intermediate is cationic).