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Updated: May 12, 2026
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[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
How Silver Additives Promote Copper-Catalyzed Cyclization and Alkene Transposition: A Mechanistic Study
Lan Hu1, Lihan Zhu1, Guangfan Zheng1
1Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Department of Chemistry, North-east Normal University, Changchun 130024, China.
Organic Letters
|May 11, 2026
Summary
Silver additives stabilize copper-catalyzed spirocyclic ether synthesis by forming a synergistic catalytic framework. This framework enhances key hydrogen transfer processes through intricate metal-ligand interactions, revealing a bimetallic effect.
Area of Science:
- Organic Chemistry
- Catalysis
- Computational Chemistry
Background:
- Copper-catalyzed reactions are vital for synthesizing complex organic molecules.
- Alkenol transposition/cyclization efficiently forms spirocyclic ethers.
- The role of silver (Ag) additives in these copper (Cu)-catalyzed reactions is not well understood.
Purpose of the Study:
- To elucidate the precise function of silver additives in copper-catalyzed alkene transposition/cyclization of alkenols.
- To provide a detailed mechanistic understanding of the observed bimetallic effect.
Main Methods:
- Density Functional Theory (DFT) calculations were employed to model the catalytic system.
- Quantum Theory of Atoms in Molecules (QTAIM) analyses were used to investigate electronic interactions.
- Energy Decomposition Analysis (EDA) was performed to quantify interaction energies.
Main Results:
- Silver (Ag) forms a stable, multidentate coordination framework that promotes synergistic catalysis with copper (Cu).
- Ag···C, Ag···O, Ag···H, and Ag···Cu interactions are crucial for stabilizing the hydrogen transfer step.
- EDA revealed that orbital, electrostatic, and dispersion interactions synergistically contribute to stabilization.
Conclusions:
- Silver additives play a critical role in enhancing copper-catalyzed spirocyclic ether formation through a synergistic bimetallic effect.
- The study provides a quantitative mechanistic rationale for silver's function, based on detailed electronic structure analyses.
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