Photoinduced Co-catalyzed dehydrogenative cyclization of 2-alkenylphenyl carbonyl compounds and mechanistic insights†

In this work, we present a UV-induced 6π-cyclization protocol enabling the synthesis of polysubstituted naphthol skeletons using a single cobaloxime catalyst. In addition, the dual-function photosensitizer 4CzIPN served as both an energy transfer (EnT) photosensitizer and a single electron transfer (SET) photocatalyst within the reaction, leading to the synthesis of the same skeleton under visible light irradiation. The sole by-product of the two strategies was hydrogen, offering potential utility.