Herz Reaction

Abstract

The reaction between primary aromatic amines, their salts, or N ‐acetyl derivatives with sulfur monochloride either in the presence or absence of an inert solvent to form 1,3,2‐benzothiazathiolium chlorides, known as the Herz compounds or Herz salts, and the reaction is known as the Herz reaction. The study finds that the Herz compounds decompose on heating and are difficult to purify, furthermore treatment of Herz compounds with chloroacetic acid leads to o ‐aminophenylthioglycolic acid derivatives. This reaction is used to prepare o ‐amino thiophenols and benzothiozoles.