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Updated: Aug 13, 2025

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Phosphine Oxide-Promoted Rh(I)-Catalyzed C-H Cyclization of Benzimidazoles with Alkenes
Mingzhen Lu1, Weiwei Xu1, Mengchun Ye1,2
1State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Frontiers Science Center for New Organic Matter, Tianjin 300071, China.
Abstract:
Ligands play a critical role in promoting transition-metal-catalyzed C-H activation reactions. However, owing to high sensitivity of the reactivity of C-H activation to metal catalysts, the development of effective ligands has been a formidable challenge in the field. Rh(I)-catalyzed C-H cyclization of benzimidazoles with alkenes has been faced with low reactivity, often requiring very harsh conditions. To address this challenge, a phosphine oxide-enabled Rh(I)-Al bimetallic catalyst was developed for the reaction, significantly promoting the reactivity and allowing the reaction to run at 120 °C with up to 97% yield.
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