HYDROGEN TRANSFER REDUCTION OF HEXAN-2-ONE CATALYZED BY A SILICA SURFACE-GRAFTED OSMIUM CLUSTER

The effectiveness of many transition metal complexes in catalyzing hydrogen transfer from alcohols to ketones, as well as the potential selectivity of this reaction together with its relative underutilization prompted us to study the heterogeneous reduction of hexan-2-one with propan-2-ol, using as catalyst the above-mentioned osmium cluster A grafted on silica. The hydrogen transfer reaction was carried out in a conventional stainless steel flow reactor operating at atmospheric pressure between 383 and 463 K. In the same reaction conditions, the silica support shows only a negligible catalytic activity. This reaction represents, to our best knowledge, the first example of a hydrogen transfer reaction catalyzed by a molecular cluster grafted to an inorganic oxide.