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Updated: Oct 24, 2026
![[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
Air-Compatible Indole-Based NHC-Copper Catalysts for A3 Coupling Reaction
Cai-Wei Cheng1, Chia-Chen Lin1, Po-Yu Chen1
1Department of Chemistry, National Chung Hsing University, Taichung40227, Taiwan.
Abstract:
A series of indole-based N-heterocyclic carbene (NHC) copper complexes has been developed as air-compatible catalysts for A3 coupling reactions. The optimized catalytic system efficiently promotes the three-component coupling of aldehydes, amines, and alkynes under aerobic conditions with catalyst loadings as low as 0.1 mol %. Systematic evaluation of ligand structure reveals that both electronic and steric features of the indole-derived NHC framework play key roles in modulating catalytic activity and stability under air. Notably, differences in time-dependent catalytic behavior are correlated with the air stability of the Cu-NHC complexes, providing insight into catalyst deactivation pathways. These results demonstrate the potential of indole-based NHC-copper complexes as efficient catalysts for A3 coupling reactions under operationally simple conditions.
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