Asymmetric Cyanation with the Chiral Ru–Li Combined Catalysts

Takeshi Ohkuma; Nobuhito Kurono

doi:10.1055/s-0032-1316545

Synlett, Inhaltsverzeichnis

Synlett 2012; 23(13): 1865-1881
DOI: 10.1055/s-0032-1316545

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Asymmetric Cyanation with the Chiral Ru–Li Combined Catalysts

Takeshi Ohkuma*

Division of Chemical Process Engineering, Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan, Fax: +81(11)7066598 eMail: ohkuma@eng.hokudai.ac.jp

,

Nobuhito Kurono

Division of Chemical Process Engineering, Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan, Fax: +81(11)7066598 eMail: ohkuma@eng.hokudai.ac.jp

› Institutsangaben

Abstract

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Abstract

The combined systems of phenylglycinate/BINAP/Ru(II) complex and Li compounds have been found to act as highly reactive and enantioselective catalysts for cyanosilylation and hydrocyanation of aldehydes, α-keto esters, α,β-unsaturated ketones, and N-protected aldimines. In this account, we describe the concept of catalyst design, the catalytic efficiency of the novel combined systems in the asymmetric cyanation, and the proposed reaction pathway based on the spectral analysis data.

1 Introduction

2 Cyanosilylation of Aldehydes and Ketones Catalyzed by LiCl

3 Asymmetric Cyanosilylation of Aldehydes and α-Keto Esters

3.1 Design of Chiral Ru–Li Combined Catalyst Systems

3.2 Cyanosilylation of Aldehydes

3.3 Cyanosilylation of α-Keto Esters

4 Asymmetric Hydrocyanation of Aldehydes, α,β-Unsaturated Ketones, and Aldimines

4.1 Hydrocyanation of Aldehydes

4.2 Conjugate Cyanation of α,β-Unsaturated Ketones

4.3 Strecker-Type Reaction

5 Mechanistic Considerations for Cyanosilylation of Aldehydes and Ketones

5.1 Achiral Reaction Catalyzed by LiCl

5.2 Asymmetric Reaction with the Chiral Ru–Li Combined Catalyst

6 Conclusion

Key words

aldehydes - asymmetric catalysis - cyanosilylation - hydrocyanation - imines - lithium - ruthenium - α,β-unsaturated ketones

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Referenzen

References and Notes

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