Photoinduced Regioselective Fluorination and Vinylation of Remote C(sp 3 )-H Bonds Using Thianthrenium Salts.
Mengqi LuoShibo ZhuChao YangLin GuoWujiong XiaPublished in: Organic letters (2024)
Herein, a photoredox-driven practical protocol for fluorinated alkene synthesis using easily accessible and modular thianthrenium salts with electron-withdrawing alkynes or propargyl alcohols is reported. Vinyl radical intermediates, formed by the reaction between the alkyl or trifluoromethyl thianthrenium salts and electronically diverse alkynes, can mediate the key 1,5-HAT process of regioselective C(sp 3 )-H fluorination and vinylation. This protocol provides straightforward access to structurally diverse trifluoromethyl- or distally fluoro-functionalized alkene products in 21-79% yields with a broad substrate range under mild photocatalytic conditions.