- Fe(OTf)3-catalyzed practical synthesis of 2-trifluoromethylarylimidazoles from o-arylenediamines and hexafluoroacetylacetone
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An iron-catalyzed practical synthesis of 2-trifluoromethylarylimidazoles through condensation of o-arylenediamines and hexafluoroacetylacetone followed by intramolecular addition and C–C bond cleavage in one-pot has been developed. A series of title compounds were obtained with up to 99% yield. This method is quite practical and suitable for scalable preparation due to simple experimental procedure and readily available reagents.
- Zhou, Yanmei,Shen, Guanshuo,Sui, Yuebo,Zhou, Haifeng
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- N-SUBSTITUTED HETERO-BICYCLIC COMPOUNDS AND DERIVATIVES FOR COMBATING ANIMAL PESTS II
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The invention relates to N-substituted hetero-bicyclic compounds of formula (I), to the enantiomers, diastereomers and salts thereof and to compositions comprising such compounds. The invention also relates to methods and uses of these N-substituted hetero-bicyclic compounds, and of compositions comprising thereof, for combating and controlling animal pests. Furthermore the invention relates also to pesticidal methods of applying such N-substituted heterobicyclic compounds. The N-substituted hetero-bicyclic compounds of the present invention are defined by the following formula I: wherein A, B, X, H et, R1, R2, W1, W2, W3 and W4 are defined as in the description.
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Page/Page column 83
(2013/10/21)
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- Efficient syntheses of 2-fluoroalkylbenzimidazoles and -benzothiazoles
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We report an efficient one-step route to 2-fluoroalkylbenzimidazoles and -benzothiazoles via the condensation of fluorinated carboxylic acids and aromatic diamines or aminothiophenols. Additionally, we describe the syntheses of fluoroalkyl-azabenzimidazoles, -purines, and -imidazolopyrazines. This method is high-yielding with broad scope and is operationally simple with potential application to parallel synthesis.
- René, Olivier,Souverneva, Alexandra,Magnuson, Steven R.,Fauber, Benjamin P.
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supporting information
p. 201 - 204
(2013/02/22)
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- Synthesis of a series of trifluoromethylazoles and determination of pKa of acidic and basic trifluoromethyl heterocycles by 19F NMR spectroscopy
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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.
- Jones, Brian G.,Branch, Sarah K.,Thompson, Andrew S.,Threadgill, Michael D.
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p. 2685 - 2692
(2007/10/03)
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