Studies on Benzothiazoline Derivatives. III. Reactions of 2, 2-Disubstituted Benzothiazolines with Haloacyl Halides or Acid Anhydrides

Abstract

A new ring transformation of benzothiazolines to 3-oxo-2, 3-dihydro-4H-1, 4-benzothiazines or benzothiazoles was found in the reactions of 2, 2-disubstituted benzothiazolines (3-5) with haloacyl halides. N, S-Bis (haloacyl) o-aminobenzenethiols were key intermediates of the reactions. In the case of benzothiazoline (1) and 2-methylbenzothiazoline (2), N-acylated products were obtained. Reactions with acid chlorides or acid anhydrides gave the N-acylated compounds in good yields.