Isophorone was smoothly oxidized with molecular oxygen by molybdovanadophosphate supported on the active carbon (NPMo V/C) to give 3-formyl-5, 5-dimethyl-2-cyclohexen-1- one in relatively high selectivity. The regioselectivity of the oxidation by NPMo V/C was found to be just opposite to that of the conventional oxidations. The pore size of the supports appears to be an important factor governing the regioselectivity.
