Pentafluorophenyl Group as Activating Group: Synthesis of α‐Deuterio Carboxylic Acid Derivatives via Et3N Catalyzed H/D Exchange

Abstract

AbstractWe discovered that highly regioselective H/D exchange can be achieved on the α‐position of the pentafluorophenyl (Pfp) ester using Et3N as the catalyst and D2O as the deuterium source. Our computational and experimental results showed that the Pfp group can significantly increase the acidity of the α‐hydrogen of the ester. This mild reaction condition tolerated a variety of functional groups. 90%∼98% yields and 91%∼98% deuterium incorporations were obtained with all the tested Pfp esters. Taking advantage of the high reactivity of Pfp esters, a series of valuable α‐deuterio carboxylic acid derivatives, including herbicide, drugs and drug intermediates, have been synthesized using α‐deuterio Pfp esters as precursors.magnified image