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The incorporation of the gem‐difluoromethylene (CF2) group into organic frameworks is highly sought due to the influence of this unit on the physicochemical and pharmacological properties of molecules. Herein we report an operationally simple, mild, and switchable protocol to access various gem‐difluoro compounds that employs chlorodifloroacetic anhydride (CDFAA) as a low‐cost and versatile fluoroalkylating reagent. Detailed mechanistic studies revealed that electron‐transfer photocatalysis triggers mesolytic cleavage of a C−Cl bond generating a gem‐difluoroalkyl radical. In the presence of alkene, this radical species acts as a unique intermediate that, under solvent‐controlled reaction conditions, delivers a wide range of gem‐difluorinated γ‐lactams, γ‐lactones, and promotes oxy‐perfluoroalkylation. These protocols are flow‐ and batch‐scalable, possess excellent chemo‐ and regioselectivity, and can be used for the late‐stage diversification of complex molecules. [ABSTRACT FROM AUTHOR]

We report a mild and operationally simple trifluoroacylation strategy of olefines, that utilizes trifluoroacetic anhydride as a low‐cost and readily available reagent. This light‐mediated process is fundamentally different from conventional methodologies and occurs through a trifluoroacyl radical mechanism promoted by a photocatalyst, which triggers a C−O bond fragmentation. Mechanistic studies (kinetic isotope effects, spectroelectrochemistry, optical spectroscopy, theoretical investigations) highlight the evidence of a fleeting CF3CO radical under photoredox conditions. The trifluoroacyl radical can be stabilized under CO atmosphere, delivering the trifluoroacetylation product with higher chemical efficiency. Furthermore, the method can be turned into a trifluoromethylation protocol by simply changing the reaction parameters. Beyond simple alkenes, this method allows for chemo‐ and regioselective functionalization of small‐molecule drugs and common pharmacophores. [ABSTRACT FROM AUTHOR]