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Conversion of Alkenes Into Simple or Functionalized Aldehydes by Reaction With an Ambiphilic Masked Formyl Radical.
Sheng-Qiang Lai1, Peng-Fei Zhao1, Zuo-Shuai Wang1
1State Key Laboratory of Natural Product Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, China.
Angewandte Chemie (International Ed. in English)
|July 10, 2026
Summary
Researchers developed novel reagents for masked formylation of alkenes. These reagents generate an ambiphilic masked formyl radical, overcoming limitations of traditional methods for synthesizing aldehydes.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Photocatalysis
Background:
- Formyl radical synthetic applications are limited by low electrophilicity, hindering reactions with unactivated alkenes.
- Existing masked formyl radical equivalents often exhibit insufficient reactivity.
Purpose of the Study:
- To develop novel formylating reagents capable of reacting with both activated and unactivated alkenes.
- To enable efficient masked formylation via a photocatalytic energy-transfer strategy.
Main Methods:
- Utilized N─O bond homolysis of novel (benzoyloxy)-(methylsulfonyl)methyl oxime ester reagents.
- Employed a photocatalytic energy-transfer strategy to generate masked formyl radicals.
- Applied density functional theory (DFT) calculations to assess radical electrophilicity.
Main Results:
- Generated a transient ambiphilic (benzoyloxy)-(methylsulfonyl)methyl radical with enhanced electrophilicity (1.82 eV).
- Successfully achieved aminoformylation, heteroarylformylation, and hydroformylation of various alkenes.
- Demonstrated mild deprotection of masked aldehydes to free aldehydes.
Conclusions:
- The developed reagents provide a versatile method for masked formylation of diverse alkenes.
- The enhanced electrophilicity of the generated radical overcomes previous synthetic limitations.
- This approach offers a new pathway for synthesizing functionalized aldehydes.
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