Long-Wavelength Light-Induced Group 13-15 Elementalization Reactions of Alkenes/Alkynes
Haruka Iimuro1, Antônio Junio Araujo Dias1, Ken Tanaka1
1Department of Chemical Science and Engineering, Institute of Science Tokyo, O-okayama, Meguro-ku, Tokyo, 152-8550, Japan.
Angewandte Chemie (International Ed. in English)
|January 8, 2026
Summary
Di-tert-butyl peroxide (DTBP) enables mild, long-wavelength light-driven elementalizations of alkenes and alkynes. This photosensitizer-free method uses visible LEDs for efficient radical generation and broad functional group tolerance.
Area of Science:
- Organic Chemistry
- Photochemistry
- Radical Chemistry
Background:
- Conventional radical reactions often require harsh conditions or short-wavelength UV light.
- Photosensitizers can introduce unwanted side reactions or purification challenges.
Purpose of the Study:
- To develop a mild and efficient method for elementalization of unsaturated compounds using visible light.
- To explore the mechanism of di-tert-butyl peroxide (DTBP) photolysis under long-wavelength irradiation.
Main Methods:
- Di-tert-butyl peroxide (DTBP) catalyzed reactions of alkenes and alkynes with visible LEDs (blue, green, orange).
- In situ generation of tert-butyl radicals followed by hydrogen-atom-transfer.
- Characterization using synthetic, spectroscopic, and computational methods.
Main Results:
- Successful elementalization of alkenes and alkynes using visible light (450-600 nm).
- High chemoselectivity and broad functional group tolerance were observed.
- The reaction proceeds via a vibration-mediated photolysis mechanism of DTBP.
Conclusions:
- A novel, photosensitizer-free method for elementalization using long-wavelength light was established.
- The methodology offers a mild and versatile alternative to conventional radical reactions.
- Understanding the vibration-mediated photolysis mechanism provides insights for future photochemical studies.
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