Solvent and substituent effects on the sense of the enantioselective hydrogenation of pyruvate esters catalysed by Pd and Pt in colloidal and supported forms

The outcome of the enantioselective hydrogenation of pyruvate esters using cinchona alkaloid-modified palladium catalysts is dependent on the choice of solvent/substituent; the sense of the enantioselectivity can be switched from S to R whilst maintaining the magnitude of the enantiomeric excess.