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Highly Selective Intermolecular Cross-Coupling Reactions via a Persistent Radical Effect on Ag(111)
Huaming Zhu1, Junbo Wang1,2, Yong Zhang3
1School of Physics and Information Technology, Shaanxi Normal University, Xi'an 710119, China.
Journal of the American Chemical Society
|October 25, 2025
Summary
We developed a novel radical cross-coupling reaction on silver surfaces, achieving over 99% selectivity by employing the persistent radical effect. This breakthrough overcomes a major challenge in radical chemistry.
Area of Science:
- Surface science
- Radical chemistry
- Scanning probe microscopy
Background:
- Radical cross-coupling is challenging due to homocoupling.
- Selective radical coupling is crucial for chemical synthesis.
Purpose of the Study:
- To achieve high selectivity in radical cross-coupling reactions.
- To elucidate the mechanism of radical coupling on surfaces.
Main Methods:
- Utilized persistent radical effect on Ag(111) surface.
- Employed bond-resolving scanning tunneling microscopy (BR-STM) for visualization.
- Combined experimental data with density functional theory (DFT) calculations and numerical modeling.
Main Results:
- Achieved >99% selectivity in radical cross-coupling.
- Directly visualized reaction intermediates and products at the single-bond level.
- Clarified reaction mechanism and kinetics of the persistent radical effect.
Conclusions:
- The persistent radical effect enables highly selective radical cross-coupling on surfaces.
- BR-STM is a powerful tool for studying surface reactions at the molecular level.
- Understanding radical kinetics is key for controlling surface reactions.
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