Oxidation of hydrocarbons with hydrogen peroxide catalyzed by maltolato vanadium complexes covalently bonded to silica gel

The bis(maltolato)oxo complexes of vanadium(V) and vanadium(IV) both in a soluble form and anchored to chemically modified silica gel, when used in combination with pyrazine-2-carboxylic acid (PCA), catalyze the oxidation of benzene to phenol and alkanes to the corresponding alkyl hydroperoxides with H2O2, at 40-50 degrees C. Heterogenizing the complexes leads to changes in regioselectivity and bond selectivity parameters of the alkane oxidation, and this opens new routes to the enhancement of the selectivity in oxidation processes. (C) 2007 Elsevier B.V. All rights reserved.