Selective oxidation of substituted xylenes to toluic acids by hypochlorite–Ru system under phase transfer conditions

Abstract

Instantaneous aqueous extraction of toluic acid salts is the basis for a novel selective process for the oxidation of a single methyl group of various xylenes; aqueous hypochlorite is inert towards methylbenzenes at pH higher than 9.0, however, in the presence of an organic solvent, a Ru catalyst and a phase transfer agent, rapid oxidation to benzoic acids is observed at 25 °C.

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