Diazotrifluoroethyl Radical in Photoinduced [3 + 2] Cycloadditions
Li-Ping Tu1, Jia-Yun Lai1, Cong An1
1Guizhou Provincial Key Laboratory of Innovation and Manufacturing for Pharmaceuticals, School of Pharmacy, Zunyi Medical University, Zunyi 563006, P. R. China.
Organic Letters
|January 20, 2026
Summary
This study introduces a new photocatalytic method for synthesizing trifluoromethyl-1,2,4-triazoles using hypervalent iodine reagents. The efficient process offers a practical route to valuable heterocyclic compounds under mild conditions.
Area of Science:
- Organic Chemistry
- Photocatalysis
- Synthetic Methodology
Background:
- Heterocyclic compounds, particularly triazoles, are crucial scaffolds in medicinal chemistry.
- Efficient and mild synthetic routes to functionalized triazoles are highly sought after.
Purpose of the Study:
- To develop a novel photocatalytic [3 + 2] cyclization reaction for synthesizing 5-trifluoromethyl-1,2,4-triazoles.
- To provide a practical and efficient method for accessing diverse triazole derivatives.
Main Methods:
- Utilizing a hypervalent iodine(III) reagent and N-benzylidenealkylamines.
- Employing a photocatalytic redox process under mild reaction conditions.
Main Results:
- Successful synthesis of diverse 5-trifluoromethyl-1,2,4-triazoles (41 examples, up to 97% yield).
- Demonstrated good functional group tolerance and broad substrate scope.
- Showcased applicability in late-stage functionalization of pharmaceutical derivatives.
Conclusions:
- The developed photocatalytic method offers an efficient and practical route to valuable trifluoromethyl-1,2,4-triazole scaffolds.
- The reaction's mild conditions and functional group tolerance make it a versatile tool for organic synthesis and drug discovery.
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