The chemistry of 2<i>H</i>‐3,1‐benzoxazine‐2,4(1<i>H</i>)dione (isatoic anhydrides) 1. The synthesis of <i>N</i>‐substituted 2<i>H</i>‐3,1‐benzoxazine‐2,4(1<i>H</i>)diones

Abstract

Abstract Three methods for the preparation of N ‐substituted 2 H ‐3,1‐benzoxazine‐2,4(1 H )diones (isatoic anhydrides) (1) utilizing 2‐chloro‐, 2‐nitrobenzoic acids and N ‐unsubstituted isatoic anhydrides as starting materials, are described.