In an effort to determine the nature of proton transfer during the reaction of photoexcited 1 with protic substances, irradiation of 1 in methanol-0-d was carried out. The product, which was isolated in 30y0 yield, vias characterized by infrared and mass spectral analysis as dimethyl lj2-dideuterio-5, 6-acenaphthene-dicarboxylate. That only tn-o deuterium atoms had been incorporated was indicated by the mass fragmentation pattern, which was ...
