PHOTOREDUCTION OF ETHYL PHENYLGLYOXYLATE

In the presence of electron donors, ethyl phenylglyoxylate generally f orms adducts as the result of cross-coupling between the radical pair after a proton transfer. Quenching rate constants of triplet methyl ph enylglyoxylate by hydrogen and electron donors were measured. Electron donors quench the excited state more than three orders of magnitude m ore rapidly than hydrogen donors. Quantum yields of the starting mater ial's disappearance were shown to be very different in the reaction wi th a hydrogen donor to that with an electron donor. Photoreduction by dithiane (dithiolane) situated intramolecularly was also studied. (C) 1998 Elsevier Science S.A. All rights reserved.