Synfacts 2007(3): 0285-0285  
DOI: 10.1055/s-2007-968248
Metal-Catalyzed Asymmetric Synthesis and Stereoselective Reactions
© Georg Thieme Verlag Stuttgart · New York

Key Role of the Lewis Base Position in Asymmetric Bifunctional Catalysis

Contributor(s): Hisashi Yamamoto, Matthew B. Boxer
I. Fujimori, T. Mita, K. Maki, M. Shiro, A. Sato, S. Furusho, M. Kanai*, M. Shibasaki*
The University of Tokyo, Rigaku Corporation and JASCO International Co. Ltd., Tokyo, Japan
Further Information

Publication History

Publication Date:
20 February 2007 (online)

Significance

In continuing work on Gd-centered bifunctional, bimetallic catalysts, this group describes a new ligand which differs only slightly in structure but greatly in reactivity. The only structural difference is a methylene group present in their original system, which generates a 7-, 5-, 5-membered fused system when complexed to Gd, that is absent in the new system, which is proposed to generate a 6-, 5-, 5-membered fused ring system. This new catalyst gives much higher enantioselectivity in the opening of meso-aziridines with TMSCN and surprisingly produces products with the opposite enantioselectivity.