Synthesis of activated esters of N-protected amino-acids

Abstract

A simplified method for the synthesis of activated esters of N-protected amino-acids is described. The synthesis proceeds through the aminolysis of various active esters of t-butyl or benzyl carbonate, and the leaving group displaced in this process becomes reincorporated by the additon of dicyclohexylcarbodi-imide to the reaction mixture, to give the desired compound.