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Abstract: Photoredox catalysis has traditionally been accomplished by using ruthenium or iridium polypyridyl complexes. These complexes, while robust in their application, can prove to be quite cost prohibitive. Additionally, their respective redox windows are relatively narrow, limiting the scope of substrates with which they can undergo photoinduced electron transfer. Visible light absorbing organic chromophores have proven to be cost effective alternatives to precious transition metal photoredox catalysts. Additionally, the excited state redox potentials of organic photoredox catalysts can be significantly greater than that of their inorganic counterparts allowing for the development of new methodologies on substrates that could not otherwise undergo photoinduced electron transfer. In particular, organic acridinium dyes possess photophysical properties that make them extremely potent excited state oxidants. More recently it has been demonstrated that the acridine radical in the excited state possesses and excited state oxidation potential comparable to that of dissolving metal reductants making it an excellent excited state reductant. Herein, we describe methods developed that leverage the 5.51 V of redox potential that acridinium complexes can access. Nucleophilic aromatic substitution (SNAr) is a common method for arene functionalization; however, reactions of this type are typically limited to electron-deficient aromatic halides. Herein, we describe a mild, metal_x005f_x0002_free, cation-radical accelerated nucleophilic aromatic substitution (CRA-SNAr) using a potent acridinium photoredox catalyst as an excited state oxidant. Selective substitution of arene C?O bonds on a wide array of aryl ether substrates was shown with a variety of primary amine nucleophiles. Mechanistic evidence is also presented that supports the proposed CRA-SNAr pathway. Ketone–olefin coupling reactions are common methods for the formation of carbon–carbon bonds. This reaction class typically requires stoichiometric or super stoichiometric quantities of metal reductants and catalytic variations are limited in application. Photoredox catalysis has offered an alternative method towards ketone–olefin coupling reactions, although most methods are limited in scope to easily reducible aromatic carbonyl compounds. Herein, we describe a mild, metal-free ketone–olefin coupling reaction using an excited state acridine radical super reductant as a photoredox catalyst. We demonstrate both intra and intermolecular ketone–olefin couplings of aliphatic and aromatic ketones and aldehydes. Mechanistic evidence is also presented supporting an “olefin first”ketone–olefin coupling mechanism.