Metal Free Oxidation of Alkyl Substituted Aromatics with Aqueous tert-Butyl Hydroperoxide under Microwave Irradiation.

Oxidation of alkyl substituted aromatic compounds to ketones and carboxylic acids can be achieved by 70% aqueous TBHP (tert-butyl hydroperoxide) under microwave irradiation with no additional organic solvent, metal based reagent or catalyst. Methyl aromatics (toluenes and xylenes) can be oxidized directly to the industrially important benzoic and phthalic acids. An addition of a tiny amount of ionic liquid and simultaneous cooling improves the efficiency of these oxidations. For other alkyl substituted aromatics, ketones are obtained in good yields.