Liquid-Phase Oxidation of p-Xylene using N-Hydroxyimides
نویسندگان
چکیده
In this communication, we describe p-xylene oxidation with molecular oxygen at 373 K and atmospheric pressure using N-hydroximide catalysts. p-Xylene conversion was rather high over the first 2 h of reaction and complete by the end of the experiment. The product distribution curves versus reaction time are typical of consecutive reactions. The main intermediate product is p-toluic acid. Peak concentration and the shape of its concentration profile depend heavily on the N-hydroxyimide catalyst used. This effect seems to be related to the NO–H bond dissociation energy (BDE) of the N-hydroxyimides employed. KEYWORKS p-Xylene; Terephthalic acid; Oxidation; Homogeneous catalysis; Organocatalysis
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