Photoinduced manganese-catalysed hydrofluorocarbofunctionalization of alkenes

The selective hydrofluorocarbofunctionalization of alkenes is an important synthetic strategy for efficiently constructing fluorine-containing compounds. However, existing methods often require expensive fluoroalkylating reagents and the generality of alkene substrates is usually limited to terminal alkenes. Here, we report a ligand-accelerated, manganese-catalysed hydrofluoroalkylation and hydropolyfluoroarylation of alkenes using visible light irradiation. A wide range of mono-, di- and polyfluoroalkyl, di- and trifluoromethyl, and polyfluoroaryl groups can be transferred from the corresponding fluoroalkyl bromides and polyfluoroaryl iodides to a series of structurally diverse alkenes. The utility of the process has been verified through reaction scale-up and onward synthetic transformations of the functionalized fluoroalkane products. Experimental and computational mechanistic studies revealed that a bidentate phosphine ligand significantly promotes the hydrofluoroalkylation process and plays an essential role in improving the stability and reactivity of the photoinduced manganese-centred radical.