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Updated: Feb 16, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Cationic Palladium(II)-Catalyzed Reductive Cyclization of Alkynyl Cyclohexadienones
Weiming Wu1, Tianyu Chen1,2, Junjie Chen2
1School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology , Ganzhou 341000, China.
Abstract:
A cationic palladium(II)-catalyzed reductive cyclization of cyclohexadienone-containing 1,6-enynes by using ethanol as a hydrogen donor and solvent was successfully developed. This procedure offers convenient access to cyclohexenone-annulated heterocycles under mild reaction conditions. The reaction was initiated by hydropalladation of the alkyne and was quenched by addition of the intramolecular conjugate alkene. This possible mechanism was preliminarily demonstrated by deuterium-labeling experiments.
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