Photocatalytic 1,1-Hydrofluoroalkylation of Alkynes with a Concurrent Vicinal Acylation: An Access to Fluoroalkylated Cyclic Ketones.

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(1 H)-ones, and 3,4-dihydronaphthalen-1(2 H)-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.