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Updated: Jan 26, 2026
08:25
Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
Published on: January 17, 2020
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Where Enantioselection is Set: A Mechanistic Framework for Asymmetric Hydrogen-Atom Transfer
Zhongyun Xu1, Yufeng Yang1, Yong-Qiang Zhang1
1School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China.
Angewandte Chemie (International Ed. in English)
|January 25, 2026
Summary
Asymmetric hydrogen-atom transfer (HAT) is challenging but achievable. New catalytic strategies precisely control stereochemistry during the H-transfer step, enabling high enantioselectivity in radical chemistry.
Area of Science:
- Organic Chemistry
- Catalysis
- Stereochemistry
Background:
- Hydrogen-atom transfer (HAT) is fundamental to radical chemistry.
- Achieving high enantioselectivity in asymmetric HAT is difficult due to radical reactivity and early transition states.
- Recent advancements have enabled stereocontrol at the crucial H-transfer step.
Purpose of the Study:
- To organize and review recent advances in asymmetric hydrogen-atom transfer (HAT).
- To present a mechanistic framework for understanding enantioselection in HAT.
- To highlight opportunities for future development in asymmetric radical chemistry.
Main Methods:
- Categorization of asymmetric HAT into five distinct regimes based on stereochemical control.
- Analysis of representative catalytic systems (small-molecule, metalloradical, cooperative, peptide, enzymatic).
- Illustration of how catalysts achieve enantioselection through geometric control, guided delivery, selective abstraction, or confined environments.
Main Results:
- Asymmetric HAT can be achieved with high enantioselectivity through precise catalyst engineering.
- Five distinct regimes of asymmetric HAT are identified, each with specific stereochemical logics.
- Catalysts control enantioselection by influencing radical geometry, H-delivery, abstraction, or donor-acceptor pairing.
Conclusions:
- A unified mechanistic framework spans synthetic and biocatalytic asymmetric HAT.
- Understanding the distinct stereochemical logics in each regime is crucial.
- Precisely orchestrated H-atom transfer offers significant opportunities for advancing asymmetric radical chemistry.
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