Polyphosphate Ester as a Synthetic Agent. XIII. Syntheses of 2-Substituted Benzoxazoles and Benzthiazoles with PPE

Abstract

Polyphosphate ester (PPE) was demonstrated to be a good agent in the benzazole synthesis. Benzoxazoles and benzthiazoles were prepared from o-substituted anilines and free carboxylic acids under mild conditions. Mechanisms for this reaction were briefly discussed.