Diphenylprolinol Silyl Ether as a Catalyst in an Enantioselective, Catalytic Michael Reaction for the Formation of α,α-Disubstituted α-Amino Acid Derivatives
Direct and enantioselective: Diphenylprolinolsilylether was found to catalyze the direct, asymmetric Michael reaction of 4‐substituted 2‐aryl‐2‐oxazoline‐5‐one and α,β‐unsaturated aldehydes, affording the chiral α,α‐disubstituted α‐amino acid derivatives with excellent enantioselectivity.