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The Pd-catalyzed Suzuki–Miyaura cross-coupling of alkyl- and fluoroalkyl(diphenyl)sulfonium triflates with arylboronic acids was compared. The fluorine substitution on the alkyl groups of [Ph2SR][OTf] had a big influence on the reaction. Perfluoroalkyl(diphenyl)sulfonium triflates (2b–d) were unsuccessful participants in the Pd-catalyzed phenylation of arylboronic acid under the standard conditions because of the strong electronegativity of the long-chain perfluoroalkyl groups, which underwent S Rfn bond cleavage instead. Polyfluoroalkyl(diphenyl)sulfonium triflates (2f–h) reacted with arylboronic acid to afford the phenylation product in very low yields due to the tendency of deprotonation and β-F elimination of the sulfonium salts. Eventually, (2,2,2-trifluoroethyl)diphenylsulfonium triflate (2e), methyl- or ethyl(diphenyl)sulfonium triflate (2i or 2j), and triphenylsulfonium triflate (2m) were found to be more effective reagents than other tested phenylsulfounium salts for Pd-catalyzed phenylation, which provided much higher yields of the desired products under mild conditions.

A method for the synthesis of difficult-to-access amides was developed through the coupling of sterically hindered carboxylic acids and electron deficient amines via SO2F2-mediated dehydration. The method feathers with broad substrate scope, mild conditions, excellent functional group compatibility and high yields.

An overview of reductive trifluoromethylation reactions using electrophilic ‘þCF3’ reagents Shi-Meng Wang , Jia-Bin Han , Cheng-Pan Zhang *, Hua-Li Qin *, Ji-Chang Xiao b,* a School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, 205 Luoshi Road, Wuhan 430070, China Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China