PHOTOCHEMICAL HYDROGEN ABSTRACTION BY BENZOPHENONES FROM HYDROGEN DONORS IN THE SOLID-STATE

A number of mixed crystals, prepared by resolidification of a melt containing benzophenones and various hydrogen donors (molar ratio, usually 1:1), were found, on the basis of powder X-ray diffractograms and phase diagrams, to be a mixture of the crystallites of each component. The mixed crystals underwent photochemical hydrogen transfer in the solid state. Thus the mixed crystal of benzophenone and durene gave benzopinacol and a condensation product 4 as the major products, and that of benzophenone and benzhydrol gave benzopinacol in good yield, indicating that hydrogen transfer occurred at the interface between the component crystallites.