Asymmetric induction in the reduction of optically active N-alkylidenesulphinamides by metal hydrides. A new efficient enantioselective route to chiral amines

A series of racemic and optically active N-alkylidenesulphinamides has been prepared and their reduction by metal hydrides studied. The extent of asymmetric synthesis mainly depends on the nature of the reducing species; the best results (up to 92% of stereoselectivity) are obtained with alkoxy-lithium aluminium hydrides. A new, highly enantioselective synthesis of amines is described.