Iron-Catalyzed Photochemical Defluorinative Functionalization of Polyfluorinated Aromatics.
Ke Wang1, Jia-Lin Tu1, Ao-Men Hu1
1State Key Lab of Urban Water Resource and Environment, School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China.
Organic Letters
|September 1, 2025
Summary
This study introduces a sustainable iron photocatalysis method for selective C-H functionalization. It enables defluorinative reactions on polyfluorinated aromatics using visible light, offering broad applicability.
Area of Science:
- Organic Chemistry
- Photocatalysis
- Sustainable Chemistry
Background:
- C-H functionalization is crucial in organic synthesis.
- Polyfluorinated aromatic compounds are important in pharmaceuticals and materials.
- Developing selective and sustainable methods for their modification is a key challenge.
Purpose of the Study:
- To develop a novel photocatalytic strategy for the selective defluorinative functionalization of polyfluorinated aromatics.
- To expand the synthetic utility of iron photocatalysis in constructing complex fluorinated molecules.
- To achieve site-selective C-H functionalization under mild, visible light conditions.
Main Methods:
- Utilizing iron photocatalysis under visible light irradiation.
- Employing sulfur dioxide for defluorosulfonylation.
- Using alkanes for defluorinative alkylation.
- Direct defluorinative functionalization with carboxylic acids.
Main Results:
- Achieved selective defluorosulfonylation and defluorinative alkylation of polyfluorinated aromatics.
- Demonstrated direct defluorinative functionalization with carboxylic acids.
- Exhibited excellent site-selectivity and broad substrate scope, tolerating various functional groups (e.g., cyano, acetyl, ester, CF3).
- Showed compatibility with complex, drug-like molecules.
Conclusions:
- The developed iron photocatalysis protocols offer a sustainable and selective approach for modifying polyfluorinated aromatics.
- This methodology significantly expands the synthetic toolbox for creating complex fluorinated compounds.
- The strategy holds promise for applications in medicinal chemistry and materials science.
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