Chlorination of 3, 4-Xylenol. A Reexamination -Preparation of 2, 5, 6-Trichloro-3, 4-xylenol-

Abstract

The reaction of 3, 4-xylenol with molecular chlorine or sulfuryl chloride in chloroform led to the successive formation of 6-chloro-3, 4-xylenol, 2, 6-dichloro-3, 4-xylenol, and 2, 4, 6trichloro-3, 4-dimethylcyclohexa-2, 5-dienone. The examination of the product mixtures failed to show the presence of 2, 5, 6-trichloro-3, 4-xylenol, which, hdwever, could be ebtained by the indirect method involving the treatment of 2, 6-dichloro-3, 4-dimethylphenyl trifluoroacetate with excess chlorine in trifluoroacetic acid at room temperature, followed by the mild alkaline hydrolysis of the product.
Reactions of both 3, 4-dimethylanisole and 3, 4-dimethylphenyl acetate with molecular chlorine in acetic acid resulted in the extensive alkyl-oxygen or acyl-oxygen bond fission, giving the carbonyl compounds and polymeric substance. ln contrast, 2, 4-dimethylanisole underwent nuclear hydrogen replacement to give a good yield of 3, 5, 6-trichloro-2, 4-dimethylanisole which, on prolonged contact with the chlorinating agent, was converted into 3, 4, 5, 6-tetrachloro-2, 4dimethylcyclohexa-2, 5-dienone.