A visible-light-induced remote oxyfluoroalkylation, including ketofluoroalkylation and hydroxytrifluoromethylation, of heteroalkynes is developed with dimethyl sulfoxide (DMSO) and H2O as the oxygen source, respectively. It provides a facile access to complex fluoroalkylated (Z)-alkenes in satisfactory yields with excellent regio-, stereo-, and site-selectivity. The reaction involves an uncommon vinyl radical-induced intermolecular C­(sp3)–H functionalization, thus offering a good platform for the development of remote difunctionalization of alkynes.

A visible-light-induced 1,1-hydrofluoroalkylation of alkynes with a concomitant vicinal acylation is developed using tetrahydrofuran (THF) as the hydrogen atom source. Various fluoroalkylated cyclic ketones, such as indanones, chroman-4-ones, 2,3-dihydroquinolin-4­(1H)-ones, and 3,4-dihydronaphthalen-1­(2H)-ones, can be efficiently synthesized with excellent trans-diastereoselectivity. The reaction represents the first example of 1,1-hydrofluoroalkylation of alkynes, thus providing a novel method for the construction of fluoroalkanes.

Traditional methods for the transformation of N-allyl ynamides rely on the formation of a ketenimine intermediate or its equivalent, while novel reaction modes remain to be developed. Herein, a cascade...

Fluoroalkylated alkenes are of significant importance in life sciences and functional materials. The fluoroalkylation of alkynes offers an efficient method for the synthesis of functionalized fluoroalkylated alkenes. However, the current methods are often limited to 1,2-difunctionalization, while the remote fluoroalkylative difunctionalization of alkynes has been rarely developed. Herein, a novel visible-light-induced remote halo-difluoroalkylation of thioalkynes is realized with difluoroalkyl halides as the radical source, forming distally halogenated (Z)-fluoroalkylated alkenes in moderate to high yields with excellent regio-, stereo-, and site-selectivity. The notable features of this reaction include the mild reaction conditions, broad substrate scope, concurrent formation of three new chemical bonds, and a thermodynamically less stable (Z)-alkene, thus enabling it a highly attractive method for organic synthesis. It represents a new advance on the direct C-H bond halogenation. Preliminary mechanistic studies indicate a cascade radical process involving the heteroatom-induced β-fluoroalkylation of C-C triple bonds, intramolecular 1,5-hydrogen atom transfer (1,5-HAT), single electron transfer (SET) oxidation and halide addition.

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