Efficient Cu-catalyzed Atom Transfer Radical Addition Reactions of Fluoroalkylsulfonyl Chlorides with Electron-deficient Alkenes Induced by Visible Light

Fluoroalkylsulfonyl chlorides, RfSO2Cl, in which R-f= CF3, C4F9, CF2H, CH2F, and CH2CF3, are used as a source of fluorinated radicals to add fluoroalkyl groups to electron-deficient, unsaturated carbonyl compounds. Photochemical conditions, using Cu mediation, are used to produce the respective alpha-chloro-beta-fluoroalkylcarbonyl products in excellent yields through an atom transfer radical addition ( ATRA) process. Facile nucleophilic replacement of the a-chloro substituent is shown to lead to further diverse functionalization of the products.