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A simplified effective synthetic process is described for the diastereoselective synthesis of the chiral C 2 -symmetric CF 3 -ureas ( R,R )- 15 and ( S,S )- 15 from ( S )-α-phenylethylamine, glyoxal and CF 3 I. [ABSTRACT FROM AUTHOR]

A series of 1-alkyl-3-methyl-1,2,3-triazolium bis(trifluoromethylsulfonyl)imide [NTf 2 ] ionic liquids were prepared synthetically using azide–alkyne ‘click’ cyclization chemistry and their physicochemical and thermal properties were determined. Increasing the alkyl chain length resulted in increased viscosities and higher thermal transitions ( T g or T m ) with depressed molar conductivities. Walden plot analysis indicated that the ionicity of 1-butyl-3-methyl-1,2,3-triazolium [NTf 2 ] was comparable to the analogous imidazolium system and higher than the 1,2,4-triazolium equivalent. [ABSTRACT FROM AUTHOR]

An improved synthesis of 3-[3-(trifluoromethyl)-3 H -1,2-diazirin-3-yl]aniline, achieving an overall yield of 38% over seven steps is reported. Only three chromatographic separations were needed and the preparation of ∼0.7 g of the target compound was demonstrated. The stability of the diazirine in solution at room temperature while exposed to ambient light was studied. No significant degradation of the compound was observed over the course of five weeks in a 130 mM sample and only minor degradation was observed in weaker samples (10, 5, and 2.5 mM), as demonstrated by 1 H and 19 F NMR. [ABSTRACT FROM AUTHOR]

Unlike the hydrocarbon analogs, this first report of enolboration–aldolization of 3,3,3-trifluoropropanoic acid provides essentially pure anti -diastereomers of α-trifluoromethyl-β-hydroxy carboxylic acids in 77–90% yields. [ABSTRACT FROM AUTHOR]

1,1,1-Trifluoro-4,5,5-trimethoxyhex-3-en-2-one and lithium (2 Z )-1,1,1-trifluoro-5,5-dialkoxy-4-oxohex-2-en-2-olate were synthesized for the first time via direct trifluoroacetylation of 2,3-butanedione acetal derivatives. A simple and effective approach to acetal or acyl substituted CF 3 -pyrazoles, 5,5′-bis(trifluoromethyl)-3,3′-bipyrazole, and, to 5-trifluoromethylfuran-3-ones is presented. [ABSTRACT FROM AUTHOR]

A safe and facile method for the formation of 3-trifluoromethyl-5-amino-1,2,4-oxadiazoles, via a reversed addition of hydroxylamine to cyanamides, is reported. This two-pot procedure is suitable to scale-up and avoids the hazards associated with trifluoromethyl amidoxime synthesis. [ABSTRACT FROM AUTHOR]

Abstract: While 1,3-dicarbonyl compounds react with (E)-1,1,1-trifluoro-3-nitrobut-2-ene in the presence of sodium acetate to produce the target β-(trifluoromethyl)furans, their reaction with (E)-1,1,1-trichloro-3-nitrobut-2-ene, under the same conditions, took an entirely different course and gave spiro-gem-dichlorocyclopropanes bearing a 1-nitroethyl moiety, with high diastereoselectivity and in good yields. [Copyright &y& Elsevier]