Pd(II)-Hydrotalcite-Catalyzed Selective Oxidation of Alcohols Using Molecular Oxygen

A novel heterogenized Pd catalyst, palladium supported by hydrotalcite [Pd(II)-hydrotalcite], has been synthesized. The catalyst is found to be effective for the oxidation of a wide range of alcohols using molecular oxygen as a sole oxidant. In this catalytic system, various alcohols are readily converted to the corresponding aldehydes or ketones selectively in high to excellent yields. It is noteworthy that the catalyst is also applicable to the oxidation of unsaturated alcohols such as geraniol and nerol without any isomerization of an alkenic part. Another characteristic property of this heterogeneous catalyst is that a shape selectivity depending on the structure of alcohols is observed in some cases. The catalyst also has advantages such as ease of handling, easy preparation, and reusability for several times.