Notes. Studies on copper(II) complexes of ortho-quinone mono-oximes: reaction of bis(4-chloro-1,2-benzoquinone 2-oximato)copper(II) with dimethyl acetylenedicarboxylate under various experimental conditions

Abstract

In anhydrous methanol the title complex reacts with dimethyl acetylenedicarboxylate to give methyl 5-chloro-1,3-benzoxazole-2-carboxylate instead of 6-chloro-4-hydroxy-2,3-dimethoxycarbonyl-1,4-benzoxazine as in aqueous solution. The role of water in such reactions is examined and discussed.