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A new cross‐coupling of trifluoromethyl arenes has been realized via multiphoton photoredox catalysis. Trifluoromethyl arenes were demonstrated to undergo selective mono‐defluorinative alkylation under mild reaction conditions providing access to a series of valuable α,α‐difluorobenzylic compounds. The reaction shows broad substrate scope and general functional group tolerance. In addition to the electron‐deficient trifluoromethyl arenes that are easily reduced to the corresponding radical anion, more challenging electron‐rich substrates were also successfully applied. Steady‐State Stern‐Volmer quenching studies indicated that the trifluoromethyl arenes were reduced by the multiphoton excited Ir‐based photocatalyst. [ABSTRACT FROM AUTHOR]

Fluorine incorporation by concomitant fluoroalkyl radical addition to alkene or alkyne and functional group migration (FGM) represents an ingenious and robust strategy for the synthesis of structurally diverse fluorinated compounds. This account gives an overview of related studies in our group, in which three main reaction modes are discussed: 1) radical fluoroalkylative difunctionalization of unactivated alkenes via intramolecular FGM; 2) alkene difunctionalization by docking‐migration process using fluoroalkyl‐containing bifunctional reagents; 3) incorporation of fluoroalkyl group into C(sp3)−H bond via consecutive hydrogen atom transfer (HAT) and FGM. Relying on these methods, a variety of trifluoromethylation and di‐/mono‐fluoroalkylation reactions along with the migration of cyano, heteroaryl, oximino, formyl, alkynyl, and alkenyl groups have been accomplished under mild conditions. [ABSTRACT FROM AUTHOR]

The nickel‐catalyzed three‐component reductive carbonylation of alkyl halides, aryl halides, and ethyl chloroformate is described. Ethyl chloroformate is utilized as a safe and readily available source of CO in this multi‐component protocol, providing an efficient and practical alternative for the synthesis of aryl‐alkyl ketones. The reaction exhibits a wide substrate scope and good functional group compatibility. Experimental and DFT mechanistic studies highlight the complexity of the cross‐electrophile coupling and provide insight into the sequence of the three consecutive oxidative additions of aryl halide, chloroformate, and alkyl halide. [ABSTRACT FROM AUTHOR]

We report a novel asymmetric radical cyclization of alkenes via stereospecific homolytic substitution of sulfinamides. This reaction produces a variety of cyclic sulfinamides with excellent stereocontrol. The protocol features broad functional group tolerance, high product diversity, and easy accessibility to feedstocks, and outlines a new pathway for the synthesis of chiral cyclic sulfinamides. [ABSTRACT FROM AUTHOR]

Regioselective incorporation of a particular functional group into aliphatic sites by direct activation of unreactive C−H bonds is of great synthetic value. Despite advances in radical‐mediated functionalization of C(sp3)−H bonds by a hydrogen‐atom transfer process, the site‐selective vinylation of remote C(sp3)−H bonds still remains underexplored. Reported herein is a new protocol for the regioselective vinylation of unactivated C(sp3)−H bonds. The remote C(sp3)−H activation is promoted by a C‐centered radical instead of the commonly used N and O radicals. The reaction possesses high product diversity and synthetic efficiency, furnishing a plethora of synthetically valuable E alkenes bearing tri‐/di‐/mono‐fluoromethyl and perfluoroalkyl groups. Give and take: Regioselective incorporation of a particular functional group into aliphatic sites by direct activation of unreactive C−H bonds remains challenging. Herein a new protocol for the regioselective vinylation of unactivated C(sp3)−H bonds is reported. The activation of a remote C(sp3)−H bond is promoted by a C‐centered radical instead of the commonly used N and O radicals. [ABSTRACT FROM AUTHOR]

Abstract: A general and practical protocol for elusive carbo‐difluoroalkylation/ monofluoroalkylation of unactivated alkenes based on the distal functional group migration is described. A portfolio of functional groups including heteroaryl, imino, formyl, and alkynyl groups showcase the migratory aptitude. In combination with visible‐light photocatalysis, a broad range of di‐ and mono‐fluorinated alkyl ketones are readily obtained in synthetically useful yields under mild reaction conditions. [ABSTRACT FROM AUTHOR]