Catalytic Enantioselective C−C Bond Forming Conjugate Additions with Vinyl Sulfones

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.