| 摘要 |
PURPOSE:To industrially and readily obtain the titled compound in high yield, by oxidizing p-xylene with molecular oxygen in the presence of a specific heavy metal oxidation catalyst in an inexpensive lower aliphatic monocarboxylic acid as a solvent in the absence of bromine. CONSTITUTION:p-Xylene is oxidized with a gas containing molecular oxygen in 1-10pts.wt., based on 1pt.wt. total of an oxidation product consisting essentially of p-xylene and p-toluic acid present in the oxidation reaction mixture, <=3C lower aliphatic monocarboxylic acid solvent in the presence of 0.03-3wt% expressed in terms of metal based on the solvent, heavy metal oxidation catalyst consisting of cobalt and/or manganese substantially in the absence of bromine at 160-240 deg.C to give advantageously p-toluic acid useful as an intermediate for various industrial chemicals, etc., in higher yield than the conventional solventless oxidation method with suppressed formation of terephthalic acid or diphenyl type by-products, etc. |
