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Complementary Photocatalytic Toolbox: Control of Intramolecular endo- versus exo-trig Cyclizations of α-Phenyl Olefins to Oxaheterocyclic Products

Fabian Weick, Desirée Steuernagel, Arina Belov, Hans-Achim Wagenknecht*

*Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany, Email:

F. Weick, D. Steuernagel, A. Belov, H.-A. Wagenknecht, Synlett, 2022, 33, 1199-1203.

DOI: 10.1055/s-0040-1719871

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The regioselectivity of the intramolecular cyclization of bifunctional α-phenyl alkenes can be controlled simply by the choice of the organic chromophore as the photocatalyst. Whereas N,N-(4-diisobutylaminophenyl)phenothiazine catalyzes exo-trig cyclizations, 1,7-dicyanoperylene-3,4,9,10-tetracarboxylic acid bisimides catalyze endo-trig additions.

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Key Words

photochemistry, organocatalysis, tetrahydrofurans, perylene bisimide, phenothiazine, nucleophilic addition, cyclization

ID: J72-Y2022