Esterification of N-Benzyl-N-t-butoxycarbonyl-amides and Unsaturated Alcohol under Transition Metal-Free Conditions
A metal-free catalytic system for the esterification reaction of N-benzyl-N-t-butoxycarbonyl-amides with unsatu-rated alcohols was reported.With the assistance of catalytic amounts of lithium tert-butoxide,the highly reactive N-t-butoxy-carbonyl-amides were able to act as electrophiles and undergo esterification reactions with unsaturated alcohols to produce a series of unsaturated esters in excellent yields.Furthermore,this metal-free reaction system allowed relatively mild reaction conditions,making it a suitable choice for late-stage modification of natural products and drug molecules.