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A method for the synthesis of diversely substituted 3-fluoropyridines from two ketone components is described. The reaction involves photoredox coupling of α,α-difluoro-β-iodoketones with silyl enol ethers catalyzed by fac-Ir(ppy)3 under blue LED irradiation with subsequent one-pot condensation with ammonium acetate. Based on cyclic voltammetry studies, it was determined that α,α-difluoro-β-iodoketones are reduced notably easier compared to 2,2,2-trifluoro-1-iodoethane, which may be ascribed to the influence of the carbonyl group. [ABSTRACT FROM AUTHOR]

A method for the synthesis of 3-hydroxy-4,4-difluoropyrrolidines from α,α-difluoro-β-bromoketones is described. The reaction involves methylenation of the carbonyl group with tetrahydrothiophenium ylide followed by coupling with primary amines. [ABSTRACT FROM AUTHOR]

A new fluorinated silicon reagent bearing a functionalized tetrafluoroethylene fragment was prepared from two CF2 building blocks: ethyl bromodifluoroacetate and (bromodifluoromethyl)trimethylsilane. The key C-C bond-forming step involves a difluorocarbene addition/cyclopropane rearrangement sequence. The silicon reagent was coupled with aldehydes and reactive azomethines in the presence of potassium fluoride. [ABSTRACT FROM AUTHOR]

A method for the difluorohomologation of ketones accompanied by halogenation of a C-H bond is described. The reaction involves silylation, difluorocarbene addition using Me3SiCF2Br activated by a bromide ion, and halogenation of intermediate cyclopropanes with N-bromo- or N-iodosuccinimide. The whole process is performed without isolation of intermediates. The resulting α,α-difluoro-β-halo-substituted ketones can be readily converted into fluorine containing pyrazole derivatives and oxetanes. [ABSTRACT FROM AUTHOR]