Synthesis of α-CF3 ketones from alkenes and electrophilic trifluoromethylating reagents by visible-light driven photoredox catalysis

alpha-Trifluoromethyl ketones are important fluorinated intermediates and products in chemical synthesis and medicinal development. Herein, visible light-catalyzed photoredox trifluoromethylation of 1-aryl-2-alkyl substituted alkenes using an electrophilic trifluoromethylating reagent to produce alpha-trifluoromethyl ketones is reported. Two possible pathways involving either a trifluoromethyl radical or a styrene radical cation are proposed and discussed. (C) 2014 Elsevier B.V. All rights reserved.