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

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