Polymeric Difluoromethylation Reagent

Significance

Polystyrene resin supported difluoromethylsulfonium tetrafluoroborate (3) was prepared via electrophilic aromatic substitution of polystyrene resin (1; 1% DVB cross-linked) with difluoromethyl phenyl sulfoxide followed by washing with a dichloromethane solution of tetraethyl­ammonium tetrafluoroborate (an excess amount). Difluoromethylation reactions of a variety of sodium aryl and alkyl sulfonates 4 were carried out in acetonitrile at r.t. to 60 °C to give the corresponding difluoromethylsulfones 5 in good to excellent yield. Imidazoles 6 also underwent the difluoro­methyl­ation with polymeric 3 in the presence of polymeric morpholine as a solid-phase base to give N-difluoromethyl imidazolium salts 7 in excellent yield.