Highly enantioselective, catalytic conjugate addition of cyanide to α,β-unsaturated Imides

(Salen)Al-Cl complex 1a catalyzes the asymmetric conjugate addition of hydrogen cyanide to α,β-unsaturated imides in high yields and enantioselectivities. The cyanide adducts can readily be converted into a variety of useful chiral building blocks, including α-substituted-β-amino acids and β-substituted-γ-aminobutyric acids. Mechanistic data obtained thus far point to a cooperative bimetallic mechanism for nucleophile and electrophile activation. Copyright © 2003 American Chemical Society.