Benzophenone-sensitized two-photon chemistry of azoalkanes in the "laser/ liquid jet": Evidence for photoinduced hydrogen 1,2-shift in 1,3-cyclopentadiyl triplet diradicals

Article abstract of DOI:10.1016/S0040-4039(00)79683-3

While the triplet-sensitized photolysis of the bicyclicazoalkanes 1 led on denitrogenation to the corresponding bicycloalkanes 2, the laser/liquid jet photochemistry gave additionally also the cyclopentenes 3 by hydrogen 1,2-shift; the amount of the latter increased with increasing lifetime of the intermediary cyclopentadiyl triplet diradicals 4, which suggests that two-photon chemistry may operate.