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Abstract Incorporation of CF₂X groups beyond CF₃into arene scaffolds is underdeveloped despite these groups’ utility as halogen‐bond donors and as precursors to bioisosteres. Herein, we report the synthesis, characterization, and comparative photochemistry of a suite of [Ag(II)(bpy)₂O₂CCF₂X]⁺and Ag(II)(bpy)(O₂CCF₂X)₂(bpy = 2,2´‐bipyridine, X = F, CF₃, Cl, Br, H, CH₃) carboxylate complexes. We find a dramatic effect of the X substituent on the efficiency of generating CF₂X radicals by ligand‐to‐metal charge transfer (LMCT), with Ag(II) photoreduction rates varying by over an order of magnitude and quantum yields spanning over 20%. We provide insight into how electronic and structural perturbations of the Ag(II)–O₂CCF₂X core are manifested in the LMCT quantum efficiency. With this information in hand, Ag(II)‐mediated electrophotocatalytic CF₂X functionalization is carried out on a range of (hetero)arenes. This work expands the nascent field of Ag(II)‐based photocatalysis by allowing for (hetero)aryl–CF₂X functionalization directly from unactivated fluoroalkyl carboxylate precursors. 

Abstract Metalation of the polynucleating ligand^F,tbsLH₆(1,3,5‐C₆H₉(NC₆H₃−4‐F−2‐NSiMe₂^tBu)₃) with two equivalents of Zn(N(SiMe₃)₂)₂affords the dinuclear product (^F,tbsLH₂)Zn₂(1), which can be further deprotonated to yield (^F,tbsL)Zn₂Li₂(OEt₂)₄(2). Transmetalation of2with NiCl₂(py)₂yields the heterometallic, trinuclear cluster (^F,tbsL)Zn₂Ni(py) (3). Reduction of3with KC₈affords [KC₂₂₂][(^F,tbsL)Zn₂Ni] (4) which features a monovalent Ni centre. Addition of 1‐adamantyl azide to4generates the bridging μ³‐nitrenoid adduct [K(THF)₃][(^F,tbsL)Zn₂Ni(μ³‐NAd)] (5). EPR spectroscopy reveals that the anionic cluster possesses a doublet ground state (S=). Cyclic voltammetry of5reveals two fully reversible redox events. The dianionic nitrenoid [K₂(THF)₉][(^F,tbsL)Zn₂Ni(μ³‐NAd)] (6) was isolated and characterized while the neutral redox isomer was observed to undergo both intra‐ and intermolecular H‐atom abstraction processes. Ni K‐edge XAS studies suggest a divalent oxidation state for the Ni centres in both the monoanionic and dianionic [Zn₂Ni] nitrenoid complexes. However, DFT analysis suggests Ni‐borne oxidation for5. 

Lewis acid catalyzed condensation of pyrrole and 4-fluoro-2,6-dimethylbenzaldehyde followed by chemical oxidation afforded the corresponding chlorin along with the parent porphyrin. The subsequent metalation of the porphyrin-chlorin mixture in the presence of Zn(OAc)₂•2H₂O afforded Zn monoand di-hydroxychlorins in addition to the Zn porphyrin in a one-flask synthesis. This new direct hydroxylation reaction eliminates the need for highly toxic OsO₄and H₂S that are traditionally used for the generation of hydroxy chlorins. In addition to the full characterization of the zinc chlorins, we present cyclic voltammograms, steady-state absorption, and emission profiles of this rarely available class of compounds. Our findings show that Zn mono- and di-hydroxychlorins are stable compounds that possess exceptionally long triplet excited states in solution, making them promising candidates for photodynamic therapy.