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Updated: May 10, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Synthesis and reactivity of dibenzoselenacycloheptynes
Gabriela de Almeida1, Lisa C Townsend, Carolyn R Bertozzi
1Departments of Chemistry and Molecular and Cell Biology and Howard Hughes Medical Institute, University of California , Berkeley, California 94720, United States.
Abstract:
Dibenzoselenacycloheptynes were prepared in three steps from commercially available reagents and trapped in situ with benzyl azide to form the corresponding triazoles. Surprisingly, the dibenzoselenacycloheptynes also abstracted hydrogen atoms from solvents such as THF or toluene, forming dibenzoselenacycloheptene products. These alkenyl compounds arise from a hydrogen transfer reaction from solvent to the unisolable intermediate, and we postulate that the reaction proceeds via a radical mechanism originating from the strained alkynyl bond that has unusually high radical character.
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