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Cooperative Bimetallic Radical Catalysis Enables Asymmetric Hydrogen-Atom Transfer
Jian Shen1, Fangkun Wang1, Zhiyuan Ma1
1School of Chemistry and Chemical Engineering, State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, P. R. China.
Journal of the American Chemical Society
|July 25, 2025
Summary
This study introduces cooperative bimetallic catalysis for asymmetric hydrogen-atom transfer (HAT) reactions, avoiding carbon radicals. This novel method expands the scope of HAT chemistry using diverse hydrogen donors.
Area of Science:
- Radical Chemistry
- Organometallic Catalysis
- Asymmetric Synthesis
Background:
- Asymmetric hydrogen-atom transfer (HAT) reactions are crucial for stereocontrol in radical chemistry.
- Current methods often rely on carbon-centered radicals and weak X-H bonds, leading to racemic byproducts and limited donor options.
Purpose of the Study:
- To develop a new strategy for asymmetric HAT reactions that avoids carbon radical intermediates.
- To enable the use of unconventional hydrogen donors in stereoselective radical transformations.
Main Methods:
- Cooperative bimetallic catalysis using two titanium catalysts.
- Independent activation of hydrogen donor and acceptor.
- Concerted hydrogen-atom transfer mechanism.
Main Results:
- Demonstrated asymmetric HAT without forming carbon radicals.
- Achieved excellent stereochemical control.
- Expanded the scope of usable hydrogen donors, including imidazole, overcoming X-H bond limitations.
Conclusions:
- Cooperative bimetallic catalysis offers a novel pathway for asymmetric HAT.
- This approach provides a sustainable platform for stereoselective radical reactions.
- The dual activation and concerted HAT mechanism are supported by mechanistic studies.
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