Visible-Light Photoredox-Catalyzed Three-Component Tandem Trifluoromethylation / Gem-Difluoroallylation of Alkenes

Abstract

An efficient, redox-neutral and visible-lightinduced three-component tandem trifluoromethylation / gemdifluoroallylation reaction of electron-rich alkenes is described. Trifluoromethyl (—CF₃) radical is generated from commercially available sodium trifluoromethanesulfinate (CF₃SO₂ Na), which is matched with the electron-rich alkene and α-trifluoromethyl alkene in turn, and finally, the polyfluoroolefin is obtained by β-F elimination. The advantages of this method are mild reaction conditions, excellent functional-group tolerance, broad substrate scope, and high reaction efficiency, which provides an opportunity for the late-stage modification of pharmaceuticals and natural product derivatives.

Keywords

radical addition / trifluoromethylation / gemdifluoroallylation / alkene

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Funding

National Natural Science Foundation of China(2199121)