Enantioselective Synthesis of Differently Protected 1,2-Diamines via α-Alkylation of Dibenzylaminoacetaldehyde SAMP-Hydrazone

Abstract

Chiral, unsymmetrically and differently protected 1,2-diamines 4 were prepared in moderate to good overall yields and with high asymmetric inductions (ee = 91-99%) by α-alkylation of N,N-dibenzylaminoacetaldehyde SAMP-hydrazone (S)-2 with subsequent oxidative cleavage to the corresponding α-aminonitriles, reduction to the diamines, and protection of the latter.