Catalytic enantioselective C-C bond forming conjugate additions with vinyl sulfones
Hongming Li1, Jun Song, Xiaofeng Liu
1Department of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, USA.
Abstract:
In this communication, we describe the development of the first highly enantioselective catalytic conjugate addition to vinyl sulfones. Promoted by readily accessible organocatalysts derived from C6'-OH cinchona alkaloid derivatives and under mild, air- and moisture-tolerant conditions, conjugate additions of a wide range of alpha-cyanoacetates bearing either an alpha-aryl or an alpha-alkyl substituent to vinyl sulfones proceeded in excellent enantioselectivity and high yield. Consequently, this efficient and operationally simple enantioselective C-C bond forming conjugate addition provides a new and useful approach for the enantioselective construction of all-carbon quaternary stereocenters.
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