Photoredox Catalysis-Enabled C–H Difluoromethylation of Heteroarenes with Pentacoordinate Phosphorane as the Reagent
Huanhuan Song, Jing Li, Yinbin Zhang, Ke Chen, Le Liu, Junjie Zhang, Xin‐Hua Duan, Mingyou Hu
Abstract
Difluoromethylated heterocyclic compounds have found broad applications in numerous bioactive molecules. Herein, we report photoredox catalysis-induced direct C–H difluoromethylation of heterocycles by using bis(difluoromethyl) pentacoordinate phosphorane (PPh 3 (CF 2 H) 2, 1 ) as the reagent. A variety of heterocycles, such as quinoxalin-2(1 H )-one, thiophene, indole, and coumarin, are readily tailored with a difluoromethyl group. The method is featured as transition-metal-free by using an organic compound Erythrosin B as the catalyst and O 2 as the oxidant.
Topics & Concepts
PhosphoraneReagentChemistryCatalysisPhotoredox catalysisIndole testThiopheneCombinatorial chemistryCoumarinMedicinal chemistryOrganic chemistryPhotochemistryPhotocatalysisFluorine in Organic ChemistryCatalytic C–H Functionalization MethodsRadical Photochemical Reactions