Towards a molecular understanding of asymmetric heterogeneous catalysis: Hydrogenation of 1-phenyl-1,2-propanedione

The present work comprises a detailed investigation of a complex reaction system, revealing features of reaction mechanisms that are general for asymmetric heterogeneous catalysis. Heterogeneous enantioselective hydrogenation of 1-phenyl-1,2-propanedione was studied over cinchonidine modified Pt catalysts producing (R)-1-hydroxy-1-phenylpropanone as the main product with an enantiomeric excess (ee) of 65% at maximum yield, which could be further increased above 90% due to kinetic resolution. The results of kinetic studies in batch and continuous reactors, catalyst screening and characterization results, as well as quantum chemical calculations, are summarized, and pertinent mechanistic aspects are discussed.