Asymmetric Conjugate Silyl Addition by Combined Copper/Chiral Amine Catalysis

Significance

The method described employs a chiral amine to activate the electrophile through an iminium intermediate and provides a chiral environment. The silyl nucleophile is simultaneously activated by copper. The resulting β-silyl aldehyde is obtained in good yield and high enantioselectivity. The method is applicable to aliphatic and aromatic R groups as well as to β-disubstituted enals. This report is an excellent contribution to organo/metal combined catalysis for asymmetric synthesis.