Exogenous Photosensitizer-, Metal-, and Base-Free Visible-Light-Promoted C–H Thiolation via Reverse Hydrogen Atom Transfer
- 21 December 2018
- journal article
- research article
- Published by American Chemical Society (ACS) in Organic Letters
- Vol. 21 (1) , 237-241
Abstract
Visible-light-driven, intramolecular C(sp2)–H thiolation has been achieved without addition of a photosensitizer, metal catalyst, or base. This reaction induces the cyclization of thiobenzanilides to benzothiazoles. The substrate absorbs visible light, and its excited state undergoes a reverse hydrogen-atom transfer (RHAT) with 2,2,6,6-tetramethylpiperidine N-oxyl to form a sulfur radical. The addition of the sulfur radical to the benzene ring gives an aryl radical, which then rearomatizes to benzothiazole via RHAT.Keywords
Funding Information
- Natural Science Foundation of Jiangsu Province (BK20161276)
- National Natural Science Foundation of China (21471108, 21771131, 21773163, 21531006)
- Suzhou Municipality (SZS201708)
- Priority Academic Program Development of Jiangsu Higher Education Institutions
- State Key Laboratory of Organometallic Chemistry (2018kf-05)
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