EFFICIENT OXIDATION OF PHENYL GROUPS TO CARBOXYLIC-ACIDS WITH RUTHENIUM TETRAOXIDE - A SIMPLE SYNTHESIS OF (R)-GAMMA-CAPROLACTONE, THE PHEROMONE OF TROGODERMA-GRANARIUM

The oxidation of aromatic rings to carboxylic acids with ruthenium tetraoxide is shown to be a very efficient and simple reaction using periodic acid as the stoichiometric oxidant in a biphasic solvent system (CCl4, CH3CN, H2O). The reaction can be very sensitive to the nature of the ring substituents when more than one aromatic ring is present. The procedure is compatible with other functional groups except for those that are quite acid sensitive. A simple synthesis of (R)-y-caprolactone employs Sharpless asymmetric epoxidation and the presented oxidation procedure as key steps. © 1990, American Chemical Society. All rights reserved.