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Molecular Ag(II) complexes are superoxidizing photoredox catalysts capable of generating radicals from redox-reticent substrates. In this work, we exploited the electrophilicity of Ag(II) centers in [Ag(bpy)₂(TFA)][OTf] and Ag(bpy)(TFA)₂(bpy, 2,2′-bipyridine; OTf, CF₃SO₃^–) complexes to activate trifluoroacetate (TFA) by visible light–induced homolysis. The resulting trifluoromethyl radicals may react with a variety of arenes to forge C(sp²)–CF₃bonds. This methodology is general and extends to other perfluoroalkyl carboxylates of higher chain length (R_FCO₂^–; R_F, CF₂CF₃or CF₂CF₂CF₃). The photoredox reaction may be rendered electrophotocatalytic by regenerating the Ag(II) complexes electrochemically during irradiation. Electrophotocatalytic perfluoroalkylation of arenes at turnover numbers exceeding 20 was accomplished by photoexciting the Ag(II)–TFA ligand-to-metal charge transfer (LMCT) state, followed by electrochemical reoxidation of the Ag(I) photoproduct back to the Ag(II) photoreactant. 

Pnictogen complexes are ideal for mediating multi-electron chemical reactions in two-electron steps. We report an Sb( v ) bis-μ-oxo corrole that photochemically oxidises the C–H bonds of organic substrates. In the case of toluene, the substrate is oxidised to benzaldehyde, a rare example of a four-electron photoreaction.