Diastereoselective Construction of α-Fluoroalkyl Cycloalkanols via Radical Alkylation of α-Fluoroalkyl Ketones

α-Fluoroalkyl(Rf)alcohols are privileged motifs in drugs and pharmaceutically active compounds.As such,it is highly desirable to develop efficient methods for assembling these scaffolds.Herein,a visible-light-induced cascade radical cyclization of alkenyl fluoro-alkyl ketones is developed,producing a variety of decorate α-Rf cycloalkanols in promising yields with up to＞20∶1 dr selectivity.A radical chain mechanism involving an intramolecular radical addition to the α-Rf carbonyl group and a subsequent intermolecular hydrogen atom transfer(HAT)has been proposed.Density functional theory(DFT)calculations indicate that a fluorine effect con-tributes to the radical addition to carbonyls by lowering the π*(C=O)orbital energy of CORf and energy barrier of the HAT between alkoxy radicals and THF,which may be valuable for controllable transformations of fluorinated molecules.