EFFICIENT H2O2 OXIDATION OF ALKANES AND ARENES TO ALKYL PEROXIDES AND PHENOLS CATALYZED BY THE SYSTEM VANADATE-PYRAZINE-2-CARBOXYLIC ACID

H2O2 oxidizes cyclohexane and other alkanes in CH3CN at 20-70°C in the presence of the catalyst Bu4NVO3-pyrazine-2-carboxylic acid (ratio 1: 4) to afford, after reduction with PPh3, the corresponding alcohol and carbonyl derivatives (the ratio decreases from 12 to 4 on raising the temperature from 20 to 70°C). The product yield reaches 46%, based on H2O2, and the turnover number is ca. 1000. The oxidation appears to give predominantly alkyl peroxides. which are partially decomposed in the course of the reaction. Peroxides can be formed when alkyl radicals, generated from alkanes, and radical-like species react with O2 or abstract OOH groups from the vanadium complex. Benzene and its alkyl derivatives are oxidized to produce phenols as well as side-chain oxidation derivatives. © 1993 Academic Press, Inc.