Radical Bromocyclization of Alkynes for the Synthesis of Thio-Flavonoids and Benzothiophenes
Abstract
A highly efficient and versatile strategy has been developed for the synthesis of 3-brominated thioflavonoids and benzothiophenes from readily available alkynes by using tetrabutylammonium bromide (TBAB) as the bromine source. This transformation proceeds smoothly via photocatalyzed, regioselective bromination/cyclization under metal- and additive-free conditions, with excellent functional group tolerance. This protocol enables the efficient construction of biologically relevant brominated heterocycles in up to 99% yield for 37 examples, thus offering a valuable protocol for directly introducing bromine into diverse thioflavonoids and benzothiophenes.
Fields of Study & Subjects
Vanadium and Halogenation Chemistry
Sulfur-Based Synthesis Techniques
Catalytic C–H Functionalization Methods
Publication details
- Journal / source
- The Journal of Organic Chemistry
- Publisher
- American Chemical Society (ACS)
- Volume
- 91
- Issue
- 5
- Pages
- 2134–2140
- Publication date
- 28 January 2026
- Language
- EN