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Updated: Oct 25, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Direct C6-Alkynylation of Indoles by Palladium/Norbornene Cooperative Catalysis
Shengrong Chen1, Jinghong Wu1, Hongya Zhu1
1State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou350116, China.
Abstract:
C6-H alkynylation of indoles is a highly attractive yet challenging transformation Herein we report a palladium/norbornene cooperative catalysis strategy that enables direct and regioselective C6-H alkynylation of indoles. The method exhibits broad substrate generality, accommodating a wide range of functional groups, fused heterocycles, and complex bioactive molecules. Mechanistic studies reveal that neither C-H cleavage step is turnover-limiting and that both the palladium catalyst and ethynyl benziodoxolone participate in the turnover-limiting step.
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