The copper-promoted reaction of o-halogenodiarylazo-compounds with nucleophiles. Part 3. The copper-promoted reaction of o-bromodiarylazo-compounds with carboxylate ions. A novel method for the preparation of o-hydroxydiarylazo-compounds

Abstract

o-Bromo-o′-acetylaminodiarylazo-compounds react with potassium acetate in the presence of copper(II) acetate in Bipolar aprotic solvents to give the copper(II) complex of the corresponding o-hydroxy-o′-acetylaminodiarylazo-compounds in good yield. The reaction proceeds via the intermediate o-acetoxy-o′-acetylaminodiarylazo-compound which undergoes facile, in situ, copper-promoted hydrolysis. When the diarylazo-compound contains two o-bromine atoms only one is replaced, with a single exception.