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Reported herein is a novel photoredox‐catalyzed approach for ether synthesis and it involves alkoxyl radicals generated from N‐alkoxypyridinium salts. A wide range of alkenes are smoothly difunctionalized in an anti‐Markovnikov fashion, affording various functionalized alkyl alkyl ethers. Notably, this mild process tolerates a number of functional groups and is efficiently carried out under both batch and flow conditions. Importantly, electron paramagnetic resonance (EPR) experiments by spin trapping were carried out to characterize the radical intermediates involved in this radical/cationic process. Falling into a trap: Alkoxyl radicals generated under visible light photoredox catalysis from N‐alkoxypyridinium salts were efficiently trapped by alkenes in an intermolecular fashion under either batch or flow conditions. This alkoxylation strategy provides access to a wide variety of functionalized alkyl alkyl ethers by the difunctionalization of alkenes with perfect anti‐Markovnikov selectivity. [ABSTRACT FROM AUTHOR]

We report the first use of N-trifluoromethylthiosaccharin as the source of SCF3 radical under photoredox catalysis. This allowed an efficient and general visible-light-mediated carbotrifluoromethylthiolation of alkenes. Under the optimized conditions using fac-[Ir(ppy)3] as the photocatalyst, various N-aryl acrylamides as well as a wide range of substituted styrenes can readily be difunctionalized in an intra- or intermolecular fashion, affording the corresponding SCF3-containing products in good to excellent yield. Importantly, the formation of this SCF3 radical along with other key radical intermediates was unambiguously demonstrated thanks to spin trapping/electron paramagnetic resonance (ST/EPR) experiments, which enabled a clear understanding of the reaction mechanism. [ABSTRACT FROM AUTHOR]

Reported herein is the use of S-perfluoroalkyl sulfilimino iminiums as a new source of RF radicals under visible-light photoredox catalysis (RF=CF3, C4F9, CF2Br, CFCl2). These shelf-stable perfluoroalkyl reagents, readily prepared on gram scale from the corresponding sulfoxide using a one-pot procedure, allow the efficient photoredox-induced oxyperfluoroalkylation of various alkenes using fac-Ir(ppy)3 as the photocatalyst. Importantly, spin-trapping/electron paramagnetic resonance experiments were carried out to characterize all the radical intermediates involved in this radical/cationic process. [ABSTRACT FROM AUTHOR]

Benzo[1,3,2]dithiazole‐1,1,3‐trioxides are bench‐stable and easy‐to‐use reagents. In photoredox catalysis, they generate methyl and perdeuteromethyl radicals which can add to a variety of radical acceptors, including olefins, acrylamides, quinoxalinones, isocyanides, enol silanes, and N‐Ts acrylamide. As byproduct, a salt is formed which can be regenerated to the original methylating agent. Flow chemistry provides an option for reaction scale‐up further underscoring the synthetic usefulness of these methylation reagents. Mechanistic investigations suggest a single‐electron transfer (SET) pathway induced by photoredox catalysis. [ABSTRACT FROM AUTHOR]