Oxidative cyclizations. I. The mechanism of the oxidation of ortho-substituted anilines with phenyliodoso acetate

Abstract

A comparison has been made of the types of ortho substituents which can be incorporated into a new heterocyclic ring by pyrolysis of aryl azides or during oxidation of anilines with phenyliodoso acetate. The results enable a new mechanism to be proposed for the amine oxidation. In its key step, the ortho substituent displaces iodobenzene from an intermediate iodoso ester to form the cyclic oxidation product. A competing reaction path involves homolysis of this iodoso ester to yield the free-radical precursors of azo compounds.