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Updated: Jul 18, 2026

Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Fast processes and intermediates in photochemistry of 7-dimethyl-germanorbornadiene
Margarita V Kaletina1, Victor F Plyusnin, Vyacheslav P Grivin
1Institute of Chemical Kinetics and Combustion SB RAS, 630090, Novosibirsk, Russia.
Abstract:
Laser pulse photolysis experiments have shown that the triplet excited-state of 1,2,3,4-tetraphenylnaphthalene (TPN) is one of the primary intermediates of the photochemical transformation of 7,7'-dimethylgerma-1,4,5,6-tetraphenyl-2,3-benzo-norbornadiene (GNB) in hexane solution. The molar absorption of T-T absorption and the quantum yield of the intersystem crossing of TPN were determined from the triplet-triplet energy transfer. The scheme of GNB photocleavage has been suggested where the triplet excited TPN originated from the triplet state of biradical through cleavage of the second C-Ge bond, the latter being generated from the excited singlet state of the initial GNB after the cleavage of the first C-Ge bond and the intersystem crossing. Other channels of GNB's chemical transformation have been discussed.
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