CIDEP Study of the Photoreduction of Aromatic Ketones with Alkoxides in Alcohols

The photoreductions of xanthone and benzophenone with alkoxides in several alcohols were studied by observing CIDEP. The total emission spectra, observed after the photoexcitation, were assigned to the ketone anion radicals having TM spin polarization. The dependence of the spectral line width upon alkoxides indicates the existence of a hyperfine interaction between the ketone anion radical and the alkali metal cation, even in the early stage of the photochemical reaction in an alcoholic media. A careful analysis of the spectral pattern leads to the conclusion that the counter radical of the ketone anion interacting as a geminate pair which is responsible for the RPM polarization, is other than a methoxyl radical in these systems.