Oxidation of alkanes with hydrogen peroxide catalyzed by Schiff base complexes covalently anchored to polyoxometalate

The catalytic activity of a hybrid compound [Fe(salen)-POM] (1) consisting of metallosalen moiety, [FeIII(salen)Cl], covalently linked to a Keggin type polyoxometalate, K8SiW11O39 (POM), in the oxidation of hydrocarbons with hydrogen peroxide was investigated. Reaction products were identified by gas chromatography and satisfactory yields were obtained. While, the Fe(salen)-POM catalyst showed high catalytic activity and product selectivity in the oxidation reactions, the metallosalen alone, [FeIII(salen)Cl], showed very poor catalytic activity in these reactions. The ability of various transition metal ions in this oxidation system was also investigated. Among a series of hybrid compounds, Fe(salen)-POM showed the highest activity.