A carboxylic acid deoxygenation-based radical-polar crossover process for modular access to functionalized
Haiyan Ding1, Yan Li1, Li Zhang2
1Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials and Ministry-of-Education Key Laboratory for Synthesis and Application of Organic Functional Molecules, Hubei University, No. 368 YouyiDadao, Wuhan 430062, China. liyanok@hubu.edu.cn.
Organic & Biomolecular Chemistry
|April 21, 2026
Summary
A new photoredox-catalyzed method enables the synthesis of cyclopropane compounds from carboxylic acids and tosylates. This deoxygenation strategy efficiently creates arylformylmethyl cyclopropanes and related chromanones.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Carboxylic acids are versatile starting materials in organic synthesis.
- Photoredox catalysis offers mild and efficient reaction conditions.
- Radical-based transformations are valuable for constructing complex molecules.
Purpose of the Study:
- To develop a novel photoredox-catalyzed strategy for synthesizing cyclopropane derivatives.
- To utilize acylative coupling of carboxylic acids with homoallyl tosylates.
- To explore a deoxygenation-based radical-polar crossover process.
Main Methods:
- Photoredox catalysis
- Acylative coupling
- Radical-polar crossover
- Deoxygenation
- Synthesis of arylformylmethyl cyclopropanes
- Synthesis of 3-(cyclopropylethyl)chroman-4-ones
Main Results:
- Successfully developed a photoredox-catalyzed strategy for preparing arylformylmethyl cyclopropanes.
- Achieved acylative coupling of (hetero)aryl carboxylic acids with homoallyl tosylates.
- Demonstrated the feasibility of the deoxygenation-based radical-polar crossover process for synthesizing chromanones.
Conclusions:
- The developed method provides an efficient route to valuable cyclopropane-containing compounds.
- The strategy is applicable to both simple and complex substrates, including alkene-tethered carboxylic acids.
- This work expands the utility of photoredox catalysis in organic synthesis.
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