Acylation of N-Boc-N’-COCF3 protected hydrazine

Abstract

Within the scope of the present thesis acylation of N-Boc-N’-COCF3 protected hydrazine was investigated. Acetic anhydride, benzoyl and butanoyl chlorides, activated esters and benzyl chloroformate were tested as acylating agents. The implementation of highly reactive acyl chlorides led to very good yields of hydrazines monoacylated at the Boc-protected nitrogen. Application of an excess of acyl chlorides promoted the formation of diacylated Boc-protected hydrazines and an unexpected loss of the trifluoroacetic group. Acylation by activated esters or benzyl chloroformate resulted solely in monoacylated products isolated in fair to poor yields. Reactions utilizing acetic anhydride gave no product irrespective of reaction conditions.