RESUMO
Fluorinated moieties constitute important substituents used in many applications to modify the properties of molecules. The action of DAST onto Ruppert's reagent yields to a not isolable intermediate that can then react with various primary amines to give trifluoromethanesulfinamidines and trifluoromethanesulfanylamides. Such compounds were unknown until now and constitute interesting new families of fluorinated molecules.
Assuntos
Amidas/química , Química Orgânica/métodos , Fluoretos/síntese química , Flúor/química , Espectroscopia de Ressonância Magnética/métodos , Modelos Químicos , Estrutura Molecular , Nitrogênio/química , Enxofre/químicaRESUMO
An efficient preparation of new fluorinated lithium and ammonium sulfonimides, from the corresponding sulfonyl fluorides, is reported. These sulfonyl fluorides are reacted with benzylamine, then triflated. Due to the high leaving ability of fluorinated sulfonimides, the formed N-benzylsulfonimides are simply debenzylated with an alcohol. Finally, the intermediate oxonium sulfonimides are neutralized, in situ, by various bases. The obtained sulfonimides are potential electrolytes for lithium batteries or fuel cells.
RESUMO
An efficient preparation of several polyfluoroalkanesulfonyl fluorides is reported. This method, based on the synthesis of polyfluoroalkyl trimethyl silanes (precursors of polyfluoroalkylsulfinates) as intermediates, allows the successive transformations to be carried out in one pot. Moreover, these sulfonyl fluorides can be obtained from the corresponding sulfinates by electrophilic fluorination. This original approach avoids isolation and purification of some thermally or hydrolytically unstable intermediates. A series of new sulfonyl fluorides have been thus prepared from halogenodifluoromethylated precursors RCF2X (X = F, Br; R = ArC(O), ArS(O)n(CF2)m; n = 0, 1, 2; m = 1, 2) and have been transformed into the corresponding lithium sulfonates, which have potential applications as electrolytes for lithium batteries.
RESUMO
Beta-fluoroalkylated enones are efficient dienophiles in Diels-Alder cycloadditions to prepare various fluorinated cylic compounds. However, the presence of the fluoroalkyl moiety modifies the reactivity and the selectivity of these cycloadditions.
RESUMO
Various trifluoroacetamides and trifluoromethanesulfinamides, derived from chiral silylated amino alcohols, have been synthesized with the goal of achieving enantioselective nucleophilic trifluoromethylation. The best results were obtained with (R)-phenylglycinol derivatives, but the ee values did not exceed 30 %.
RESUMO
The syntheses of various alpha-trifluoromethylated nitrogen heterocycles have been achieved from readily available alpha-(trifluoromethyl)homoallylamine through a ring-closing metathesis.
RESUMO
Ethers of trifluoroacetaldehyde hemiaminals can undergo dehydrofluorination under basic conditions to provide ethers of difluoroketene hemiaminals. The latter behave as equivalents of difluoroacetamide or difluoroacetate anions towards various electrophiles, yielding a range of difluoromethylcarbonyl products.
Assuntos
Fluoracetatos/síntese química , Amidas/síntese química , Compostos de Flúor/síntese química , Compostos de Flúor/químicaRESUMO
Under Lewis acid activation, hemiaminals of trifluoroacetaldehyde and related (fluoroalkyl)aldehydes generate iminium species that can react with various nucleophiles to provide fluorinated amines.
RESUMO
Alkyl and aryl trifluoromethanethiosulfonates(1) (or selenosulfonates) were prepared in one step either from alkyl and aryl sulfenyl (or selenenyl) chlorides and sodium trifluoromethanesulfinate (3) or, more generally, from disulfides (or diselenides), 3, and bromine. The second method involved trifluoromethanesulfonyl bromide as key intermediate. Benzenethiosulfonates were obtained in a similar way from disulfides, benzenesulfinate, and bromine but benzeneselenosulfonates could not be obtained by the same method from diselenides.