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Updated: Sep 14, 2025

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Visible-Light-Triggered and Rhodamine B-Catalyzed Thiolation of Bromoalkynes: Accessing Alkynyl Thioethers
Rekha Bai1, Yu-Ling Chiu1, Indrajit Karmakar1
1Department of Chemistry, National Chung Hsing University, Taichung City, Taiwan 402, R.O.C.
None:
A visible-light-mediated C(sp)-SII cross-coupling of 1-haloalkynes with aryl/alkyl thiols is reported. The reaction was catalyzed by Rhodamine B under purple LED irradiation in an open-air atmosphere. Rhodamine B is a basic xanthene dye that is easily degradable and highly soluble in water. A wide range of 1-haloalkynes efficiently coupled with aryl and alkyl thiols, obtained corresponding alkynyl thioethers in moderate to excellent yields. Metal-free, room temperature, easy operation, and broad substrate scope are the salient features of the established protocol.
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