New Method On Preparing P-Methylcatechol Dimethylacetate

Various synthetic methods of p-Methylcatechol and p-Methylcatechol dimethylacetate are reviewed. A commercially economic process is obtained for preparation of p-Methylcatechol and p-Methylcatechol dimethylacetate from P-Cresol by acetylization, Freis rearrangement, Dakin H D oxidation and etherification. These compounds are useful as intermediates in preparation of pharmaceutically active compounds such as anti-bactenals, coccidioststs and antioxidants. During preparation of 4-Methylcatechol, a suitable industrial-scale production process is designed from the study of the change the materials ratio, the reaction temperature and reaction time for every step of reactions. Homogeneous Dakin H D oxidation reaction can get higher yield and percent conversion compare with heteroegeneous Dakin H D oxidation reaction. The catalysts are also very important during the reaction of acetylization and Dakin H D oxidation. It was showed that the yield was more than 88%.The preparation of p-Methylcatechol dimethylacetate by the reaction of p-Methylcatechol and Methyl chloroacetate or p-Methylcatechol and Chloroacetic acid and Methyl alcohol. The one step reaction is better for industrial-scale production. The yield was over 80%. In the course of experiment, by improving and investigating technical conditions of each step of reactions, a scientific synthetic route and a favourable technical conditions have been found, it provide the basis for our industrialization.