Cobalt(II)-Azabis(oxazoline)-Catalyzed Conjugate Reduction of α,β-Unsaturated Carbonyl Compounds.

Abstract

Azabis(oxazolines) prove to be superior ligands for the enantioselective, cobalt(II)-catalyzed conjugate reduction of alpha,beta-unsaturated carbonyl compounds with sodium borohydride. beta-Trisubstituted a,p-unsaturated esters and amides as well as gamma-butenolides are readily converted to their corresponding saturated counterparts with enantioselectivities up to 97% ee.