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Coronene Bisimide as a Visible-Light-Mediated Triplet-Triplet Energy Transfer Catalyst
Divya P Sukumaran1, Frank Würthner1,2
1Julius-Maximilians-Universität Würzburg, Institut für Organische Chemie, Würzburg, 97074, Germany.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|September 8, 2025
Summary
Coronene bisimide (CBI) is a novel, heavy-atom-free photosensitizer. It efficiently catalyzes diverse reactions using visible light, offering a greener alternative to conventional sensitizers.
Area of Science:
- Photochemistry and Organic Synthesis
- Materials Science
Background:
- Photosensitization enables mild and selective photochemical transformations via excited states.
- Conventional photosensitizers often suffer from low extinction coefficients, short triplet lifetimes, and toxicity issues, frequently due to heavy atoms.
Purpose of the Study:
- To introduce coronene bisimide (CBI) as a new class of visible-light photosensitizers.
- To demonstrate CBI's efficacy in catalyzing diverse reactions using a triplet-triplet energy transfer (TTEnT) strategy.
Main Methods:
- Synthesis and characterization of coronene bisimide (CBI).
- Evaluation of CBI's photophysical properties, including absorption spectrum and triplet state lifetime.
- Application of CBI as a photosensitizer for various chemical reactions under green light irradiation via TTEnT.
Main Results:
- CBI exhibits broadband absorption from UV to green light and a high extinction coefficient.
- Efficient intersystem crossing (ISC) leads to a long-lived triplet state in CBI.
- CBI successfully catalyzes diverse reactions under green light irradiation through TTEnT.
Conclusions:
- Coronene bisimide (CBI) is a potent, heavy-atom-free visible-light photosensitizer.
- CBI overcomes limitations of conventional sensitizers, offering high efficiency and selectivity.
- CBIs represent a promising new class of sustainable photosensitizers for organic synthesis.
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