Cyclization of Azobenzenes Via Electrochemical Oxidation Induced Benzylic Radical Generation

Abstract

An electrochemical oxidation-induced cyclization of ortho-alkyl-substituted azobenzenes has been developed. The direct electrochemical benzylic C–H functionalization with respect to azobenzenes could proceed in the absence of any catalyst or external chemical oxidant to afford a number of 2H-indazole derivatives in moderate to good yields. This protocol enables the reuse of the byproduct to the same 2H-indazoles, thus significantly reducing pollution discharge in synthetic chemistry