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Abstract Fluorination of tris(2,6‐dimethoxyphenyl)‐methylium ((DMP)₃C⁺) was achieved through the partial defluorination of the methyl 2,3,5,6‐tetrafluorobenzoate via nucleophilic aromatic substitution. Using the fluorinated^2F((DMP)₃C⁺) as a precursor, fluorinated tetramethoxy‐ and dimethoxyquin‐ acridinium salts (^2F4and^2F5respectively) and trioxo‐, azadioxo‐, and diazaoxo‐ triangulenium salts (^2F6,^2F7and^2F8respectively) were synthesized successfully in good to moderate yields. Fluorination induced significant red shifts in absorption (16 to 29 nm) and emission (13 to 41 nm) maxima, and increased electrophilicity as evidenced by lower reduction potentials. X‐ray structural analysis showed distinct packing patterns compared to the non‐fluorinated analogues, indicating the presence of molecular dipoles. 

Abstract Diffusion‐limited kinetics is a key mechanistic debate when consecutive photoelectron transfer (conPET) is discussed in photoredox catalysis. In situ generated organic photoactive radicals can access catalytic systems as reducing as alkaline metals that can activate remarkably stable bonds. However, in many cases, the extremely short‐lived transient nature of these doublet state open‐shell species has led to debatable mechanistic studies, hindering adoption and development. Herein, we document the use of an isolated and stable neutral organicⁿPrDMQA radical as a highly photoreducing species. The isolated radical offers a unique platform to investigate the mechanism behind the photocatalytic activity of organic photocatalyst radicals. The involvement of reduced solvent is observed, formed by single electron transfer (SET) between the short‐lived excited stateⁿPrDMQA radical and the solvent. In our detailed mechanistic studies, spectroscopic and chemical affirmation of solvent reduction is strongly evident. Reduction of aryl halides, including difluoroarenes is presented as a model study of the conPET method. Further, the activation of N₂O, a greenhouse gas that is yet to be activated by photoredox catalysis, is showcased in the absence of a transition metal.