1868-48-0Relevant articles and documents
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Brown,H.C. et al.
, p. 4407 - 4409 (1961)
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Chambers,W.J.,Coffman,D.D.
, p. 4410 - 4412 (1961)
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Synthesis of a series of trifluoromethylazoles and determination of pKa of acidic and basic trifluoromethyl heterocycles by 19F NMR spectroscopy
Jones, Brian G.,Branch, Sarah K.,Thompson, Andrew S.,Threadgill, Michael D.
, p. 2685 - 2692 (2007/10/03)
Trifluoroacetylation at the 5-position of 3,4-dihydro-2H-pyran and the 3-position of 4,5-dihydrofuran, followed by treatment with hydrazine, gave 3-(3-trifluoromethyl-1H-pyrazol-4-yl)propanol and 2-(3-trifluoromethyl-1H-pyrazol-4-yl)ethanol, respectively.In the latter case, an intermediate dimer was isolated.Isomeric 2-(3-trifluoromethyl-1H-pyrazol-5-yl)ethanol was formed by reaction of hydrazine with 6-benzyloxy-1,1,1-trifluorohex-3-yn-2-one and deprotection.Reaction of 3-benzyloxypropylamine with 2,5-bis(trifluoromethyl)-1,3,4-oxadiazole, followed by deprotection, afforded 3-propanol.A series of 2-trifluoromethyl-1H-benzimidazoles and 2-trifluoromethyl-3H-imidazopyridines were prepared by condensation of the appropriate ortho-arenediamine with trifluoroacetic acid.Analysis of the 19F NMR spectra of the trifluoromethylazoles and of 3-trifluoromethylpyridine in aqueous solution at different pHs enabled determination of pKa values.All the compounds evaluated had one or more pKa between 1 and 13, except the triazole.Several compounds were identified as having potential use in measuring pH in biological media by 19F NMR spectroscopy.
Unsaturated nitrogen compounds containing fluorine. Part 10. Reaction of 2,5-dichloro-1,1,1,6,6,6-hexafluoro-3,4-diazahexa-2,4-diene with halide ion and oxygen- and sulphur-centred nucleophiles and of its 2,5-di-iodo analogue with reducing agents and certain nucleophiles
Eltoum, Ahmed O. A.,O'Reilly, Neil J.,Tipping, Anthony E.
, p. 101 - 110 (2007/10/02)
The azines CF3CR=NN=CRCF3 (R = F, I, PhO, 2,4-Cl2C6H3O, PhS and EtO) are formed by treatment of the title dichloroazine 1 with an excess of the appropriate nucleophile, while reaction with phosphorus (V) sulphide at 180 deg C gives 2,5-bis(trifluoromethyl-1,3,4-thiadiazole in quantitative yield.In the reaction with NaOEt, the compound CF3C(OEt)=NN=C(ONa)CF3 is also produced from the NaOH impurity present.Di-iodoazine 3b undergoes ready reaction with aniline (1:2 molar ratio) and potassium diethyl phenylmalonate (1:1 molar ratio) to afford the monosubstituted compounds PhN=C(CF3)NHN=CICF3 and (EtO2C)2PhC(CF3)=NN=CICF3, respectively.Azine 1 is not reduced by the reagents NaH, LiAlH4 and NaBH4, but di-iodoazine 3b is reduced by tri-n-butyltin hydride at c. 90 deg C to give mainly the compounds CF3CH=NN=CHCF3, CF3CH=NN=CICF3, CFCH2NHN=CICF3 and possibly CF3CH=NNHCH2CF3; with hydrogen iodide at 200 deg C, the major products are the hydroazines CF3CH=NN=CHCF3 and CF3CH=NN=CICF3 and 2,4,6-tris(trifluoromethyl)-1,3,5-triazene.