Electrochemical Benzylic C(sp³)–H Amidation via Ritter-Type Reaction in the Absence of External Mediator and Oxidant

This work is dedicated to Professor Guo-Qiang Lin on his 80^th birthday.

Abstract

A straightforward method involving electrochemical Ritter-type amidation of alkylarenes in the absence of external mediator and oxidant is described. This direct benzylic C(sp³)–H amidation utilizes cheap CH₃CN or other nitriles as the nitrogen source and trace amount of H₂O in the solvent as the oxygen and hydrogen source. A wide range of alkylarenes were found to be compatible, providing a variety of N-benzyl-substituted amides in moderate to good yields.

Key words

electrochemical oxidation - benzylic C(sp³)–H amidation - Ritter-type reaction - external mediator free - oxidant free - N-benzylamides

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