Photoredox Catalyzed (Arylthio) Difluoromethylation Of Unsaturated Carboxylic Acids

Fluorine and sulfur atoms are widely presented in various pharmaceuticals.Therefore,the groups containing both fluorine and sulfur atoms have attracted extensive interest of chemists.And the arylthiodifluoromethyl group(Ar SCF₂)has been widely used in the fields of pharmaceutical chemistry and material science because of its unique properties.However,synthetic methods for arylthiodifluoromethyl substituted compounds were less reported.In this thesis,two different types of tandem(arylthio)difluoromethylation/cyclization have been developed with(arylthio)difluoromethytriphenylphosonium as the reagent of radical(arylthio)difluoromethylation.A series of 4-(phenylthio)difluoromethylated butenolides can be synthesized in moderate to excellent yields with 2,3-allenoic acids as starting materials via radical(phenylthio)difluoromethylation/intramolecular cyclization.In addition,the(arylthio)difluoromethylatized butyrolactones can be synthesized with 4-aryl-4-pentenoic acid as starting materials through the similar reaction path.These novel products containing arylthiodifluoromethyl structure have application prospects in pharmaceutical chemistry.