Catalyst‐Free Regio‐ and Stereoselective Alkenyltrifluoromethylation of Alkynes under Visible Light Irradiation

Abstract This work demonstrates a simple, mild and efficient alkenyltrifluoromethylation of alkynes with readily available 2‐arylamino‐1,4‐naphthoquinones and Togni reagent as coupling partners. With 2‐arylamino‐1,4‐naphthoquinones as both photosensitizers and substrates, the title reaction proceeds smoothly in ethyl acetate under the irradiation of blue light, affording a series of CF 3 ‐functionalized alkenes in excellent regio‐ and stereoselectivity. This protocol features good tolerance of functional groups, mild reaction conditions, green solvent and no involvement of external photocatalyst and additive. Furthermore, the further modification of bioactive molecules such as Menthol, Levocetirizine and Indometacin, and the late‐stage transformations of the resulting CF 3 ‐functionalized alkenes are accomplished.