Photoinduced C(sp3)-H functionalization via the photocatalyst-free hydrogen atom transfer pathway
Yi Wei1, Yu-Qi Yang1, Xiao-Qi Yang1
1Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education & Hubei Key Laboratory of Catalysis and Materials Science, School of Chemistry and Materials Science, South-Central Minzu University, Wuhan 430074, China. huxiaoqiang@mail.scuec.edu.cn.
Chemical Communications (Cambridge, England)
|November 18, 2025
Summary
Photocatalyst-free light-promoted C(sp3)-H functionalization offers a sustainable method for molecule synthesis. This review details recent advances in hydrogen atom transfer (HAT) pathways for efficient C-H bond modification.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Sustainable Chemistry
Background:
- Direct functionalization of aliphatic C-H bonds is crucial for efficient molecular synthesis.
- Traditional methods often require expensive transition metals or photosensitizers.
- Photocatalyst-free approaches offer a greener and more cost-effective alternative.
Purpose of the Study:
- To review recent advancements in photocatalyst-free C(sp3)-H functionalization.
- To highlight methodologies utilizing the hydrogen atom transfer (HAT) pathway.
- To discuss reaction conditions, substrate scope, and mechanisms of these reactions.
Main Methods:
- Focus on light-promoted C(sp3)-H functionalization without photocatalysts.
- Categorization of methods based on photoactivation pathways.
- Analysis of reaction parameters and substrate compatibility.
Main Results:
- Demonstration of efficient C(sp3)-H functionalization via photocatalyst-free HAT.
- Expansion of substrate scope for late-stage molecular modification.
- Elucidation of reaction mechanisms for various photoactivation pathways.
Conclusions:
- Photocatalyst-free HAT represents a significant advancement in sustainable C-H functionalization.
- These methods provide environmentally benign and cost-efficient routes to complex molecules.
- Further research in this area promises broader applications in organic synthesis.
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