Highly effective and enantioselective α-amination of aldehydes promoted by chiral proline amide–thiourea bifunctional catalysts

A series of secondary amine–thiourea catalysts derived from l-proline and chiral diamine were prepared and successfully applied to the highly effective and enantioselective α-amination of unmodified aldehydes with various azodicarboxylates in excellent yields (up to 99%) and enantioselectivities (up to 99% ee) within a few minutes.