- METHOD FOR PREPARING 2,3-DICHLORO-5-TRIFLUOROMETHYLPYRIDINE WITH HIGH SELECTIVITY
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The present invention discloses a method for preparing 2,3-dichloro-5-trifluoromethylpyridine, comprising at a temperature of 100?150° C. and a pressure of 0.5?5.0 MP, in presence of at least one catalyst selected from supported metal chloride, supported zeolite molecular sieve and supported heteropolyacid, 2-chloro-5-trifluoromethylpyridine reacts with chlorine gas to obtain 2,3-dichloro-5-trifluoromethylpyridine. The preparing method provided by the present invention has advantages such as high selectivity of desired product, high utilization rate of chlorine gas, moderate process condition, simple operation and less three wastes. The present invention also discloses a preparing method for preparing 2-chloro-5-trifluoromethylpyridine, which is capable of reducing unit consumption, reducing separation cost, and improving safety compared to the prior art.
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Paragraph 0179-0216
(2020/04/24)
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- Catalyst-Free N-Deoxygenation by Photoexcitation of Hantzsch Ester
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A mild and operationally simple protocol for the deoxygenation of a variety of heteroaryl N-oxides and nitroarenes has been developed. A mixture of substrate and Hantzsch ester is proposed to result in an electron donor-acceptor complex, which upon blue-light irradiation undergoes photoinduced electron transfer between the two reactants to afford the products. N-oxide deoxygenation is demonstrated with 22 examples of functionally diverse substrates, and the chemoselective reduction of nitroarenes to the corresponding hydroxylamines is also shown.
- Cardinale, Luana,Jacobi Von Wangelin, Axel,Konev, Mikhail O.
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supporting information
(2020/02/15)
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- METHOD FOR SEPARATING AND PURIFYING 2-CHLORO-3-TRIFLUOROMETHYLPYRIDINE
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A method for separating and purifying 2-chloro-3-trifluoromethylpyridine useful as an intermediate for medicines, agrochemicals, and the like is provided. The method includes: 1) in the process of producing chloro β-trifluoromethylpyridine compounds by allowing a β-methylpyridine compound to react with chlorine and hydrogen fluoride in a reaction apparatus, allowing a β-trifluoromethylpyridine compound to react with chlorine in a reaction apparatus, or allowing a chloro β-trichloromethylpyridine compound to react with hydrogen fluoride in a reaction apparatus,2) fractionating a liquid mixture containing chloro β-trifluoromethylpyridine compounds from the reaction apparatus, and3) separating and purifying 2-chloro-3-trifluoromethylpyridine from the liquid mixture.
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Paragraph 0092-0095
(2020/02/27)
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- Production method of high-purity 2-chloro-5-trifluoromethylpyridine
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The invention provides a production method of high-purity 2-chloro-5-trifluoromethylpyridine. The production method comprises the following steps: under the action of a silicon dioxide-aluminum oxide-chromic oxide catalyst, gasifying the raw materials acrolein and propyl aldehyde, and reacting with an ammonia gas to generate 3-methylpyridine; gasifying the 3-methylpyridine and carbon tetrachloridetogether, reacting in a chlorine atmosphere to obtain 2-chloro-5-trichloromethylpyridine, and performing fluoro-substitution to obtain a crude product of 2-chloro-5-trifluoromethylpyridine; heating to melt the crude product of 2-chloro-5-trifluoromethylpyridine; refrigerating and circulating in a low-temperature thermostat; cooling and crystallizing and separating to obtain recrystal; sweating the recrystal; repeating the processes of circulating, melting, recrystallizing and sweating to obtain high-purity 2-chloro-5-trifluoromethylpyridine. According to the production method provided by theinvention, 3-methylpyridine is adopted as a raw material, and the 2-chloro-5-trifluoromethylpyridine is molten, recrystallized and purified so that the product has high purity and stable yield.
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Paragraph 0028-0029
(2018/03/23)
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- Preparation method of 2-cholrine-5-trifluoromethyl pyridine
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The invention discloses a preparation method of 2-cholrine-5-trifluoromethyl pyridine. The method comprises the following steps of 1, adding a raw material 2-cholrine-5-methyl fluoride pyridine into a reaction kettle, and then adding thionyl chloride; 2, raising the temperature, and introducing chlorine into the reaction kettle; 3, after introduction of chlorine is ended, transferring the raw material into a fluorination kettle; 4, adding hydrogen fluoride which is measured well into the fluorination kettle, adding anhydrous hydrogen fluoride, raising the temperature, and conducting a reaction; 5, conducing washing and water vapor distillation on a fluoridation material, adjusting the pH value, and conducting distillation in a pressing-in rectifying tower, so that 2-cholrine-5-trifluoromethyl pyridine is obtained. According to the preparation method, thionyl chloride is adopted as solvent, so that the problem that the material contains water is solved; meanwhile, low-temperature chlorination is adopted for producing the 2-cholrine-5-trifluoromethyl pyridine chlorination material, and the foundation is laid for preparing high-purity 2-cholrine-5-trifluoromethyl pyridine.
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Paragraph 0025; 0026; 0030-0033
(2017/05/13)
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- Copper-catalysed synthesis of trifluoromethyl(hetero)arenes from di(hetero)aryl-λ3-iodanes
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An efficient synthesis of trifluoromethylated (hetero)arenes has been achieved through the regioselective copper-catalyzed trifluoromethylation of di(hetero)aryl-λ3-iodanes, employing readily available trifluoromethyltrimethylsilane. The reaction works well for both symmetrical and unsymmetrical di(hetero)aryl-λ3-iodanes with good regioselectivity and also tolerates diverse functional groups such as bromo, iodo, cyano, nitro, ester, ketone and enolizable ketone.
- Pandey, Vinay Kumar,Anbarasan, Pazhamalai
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p. 18525 - 18529
(2016/02/27)
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- TCDA: Practical Synthesis and Application in the Trifluoromethylation of Arenes and Heteroarenes
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A practical synthesis of the reagent trimethylsilyl chlorodifluoroacetate (TCDA) is reported on 50 g scale. The trifluoromethylation with TCDA was optimized, and the reaction shows very broad scope with respect to electron-deficient, -neutral, -rich aryl/heteroaryl iodides, as well as excellent functional group tolerability, such as ester, amide, aldehyde, hydroxyl, and carboxylic acid. The reagent was also applied to the late-stage trifluoromethylation of three medicinally relevant compounds. Additionally, the building block trifluoromethylpyridine and one drug related molecule Boc-Fluoxetin were synthesized in 10 g scale by this method, demonstrating its practical applications in process chemistry.
- Wang, Jian,Zhang, Xiaomin,Wan, Zehong,Ren, Feng
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p. 836 - 839
(2016/05/19)
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- New Reagent for Highly Efficient Synthesis of Trifluoromethyl-Substituted Arenes and Heteroarenes
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A new reagent trimethylsilyl chlorodifluoroacetate (TCDA) is reported for the introduction of a -CF3 group to arenes and heteroarenes. Compared with current known reagents, TCDA shows very broad scope with respect to electron-deficient, -neutral, and -rich aryl/heteroaryl iodides as well as excellent functional group tolerance, including ester, amide, aldehyde, hydroxyl, and carboxylic acid. (Chemical Equation Presented).
- Zhang, Xiaomin,Wang, Jian,Wan, Zehong
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supporting information
p. 2086 - 2089
(2015/05/13)
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- Catalytic trifluoromethylation of aryl- and vinylboronic acids by 2-cyclopropyl-1-(trifluoromethyl)benzo[ b ]thiophenium triflate
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Catalytic trifluoromethylation of aryl- and vinylboronic acids by 2-cyclopropyl-1-(trifluoromethyl)benzo[b]thiophenium triflate is described. In the presence of a catalytic amount of CuOAc and 2,4,6-collidine in ethyl acetate, the reaction proceeded in good to high yields for various substrates under mild reaction conditions at room temperature.
- Arimori, Sadayuki,Shibata, Norio
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supporting information
p. 1632 - 1635
(2015/04/14)
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- Practical method for the Cu-mediated trifluoromethylation of arylboronic acids with CF3 radicals derived from NaSO2CF3 and tert-butyl hydroperoxide (TBHP)
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A mild and practical protocol for the copper-mediated trifluoromethylation of aryl and heteroaryl boronic acids using NaSO2CF3 (Langlois' reagent) and TBHP is described. The reaction proceeds at room temperature under ambient conditions, and the products can be readily purified by extraction or column chromatography.
- Ye, Yingda,Kuenzi, Stefan A.,Sanford, Melanie S.
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supporting information
p. 4979 - 4981,3
(2012/12/12)
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- Practical method for the Cu-mediated trifluoromethylation of arylboronic acids with CF3 radicals derived from NaSO2CF3 and tert-butyl hydroperoxide (TBHP)
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A mild and practical protocol for the copper-mediated trifluoromethylation of aryl and heteroaryl boronic acids using NaSO2CF3 (Langlois' reagent) and TBHP is described. The reaction proceeds at room temperature under ambient conditions, and the products can be readily purified by extraction or column chromatography.
- Ye, Yingda,Künzi, Stefan A.,Sanford, Melanie S.
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supporting information
p. 4979 - 4981
(2013/01/15)
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- PROCESSES FOR PRODUCING 2-CHLORO-3-TRIFLUOROMETHYLPYRIDINE
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The present invention provides processes for producing 2-chloro-3-trifluoromethylpyridine which is useful as an intermediate for medicines and agrochemicals, at a high production rate in a high yield. Specifically, the present invention relates to a process for producing 2-chloro-3-trifluoromethylpyridine or a salt thereof comprising allowing 3-trifluoromethylpyridine N-oxide to react with a chlorinating agent; and also relates to a process for producing 2-chloro-3-trifluoromethylpyridine or a salt thereof comprising oxidizing 3-trifluoromethylpyridine to produce 3-trifluoromethylpyridine N-oxide and subsequently allowing the obtained 3-trifluoromethylpyridine N-oxide to react with a chlorinating agent.
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Page/Page column 3
(2012/10/18)
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- Aromatic trifluoromethylation catalytic in copper
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Cu(i)-diamine complexes were found to catalyse the trifluoromethylation of aryl iodides. In the presence of a small amount of CuX (X = Cl, Br, I) and 1,10-phenanthroline (phen), the cross-coupling reactions of iodoarenes with trifluoromethylsilanes proceeded smoothly to afford trifluoromethylated aromatics in good yields.
- Oishi, Masahiro,Kondo, Hideaki,Amii, Hideki
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supporting information; experimental part
p. 1909 - 1911
(2009/10/17)
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- Sodium Perfluoroalkane Carboxylates as Sources of Perfluoroalkyl Groups
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Sodium trifluoroacetate, in the presence of copper(I) iodide, is used as a source of trifluoromethyl to replace halogen by trifluoromethyl in benzenoid and heterocyclic aromatic systems, as well as in alkenyl and alkyl halogen compounds.The mechanism of this interesting copper-assisted process has been explored and an intermediate of the form - is proposed.Introduction of higher perfluoroalkyl groups from their respective sodium perfluoroalkane carboxylates has been demonstrated and the machanistic features are compared with those of the trifluoromethylation process.
- Carr, Gillian E.,Chambers, Richard D.,Holmes, Thomas F.,Parker, David G.
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p. 921 - 926
(2007/10/02)
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- SOME NEW 2-SUBSTITUTED 5-TRIFLUOROMETHYLPYRIDINES
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The preparation of the derivatives of 2-amino-, hydrazino-, hydroxy-, and mercapto-5-trifluoromethylpyridines via 2-chloro precursors is describes.Experimental and spectral data of the products together with those of the precursors are presented.
- Haga, Takahiro,Fujikawa, Kan-ichi,Koyanagi, Tohru,Nakajima, Toshio,Hayashi, Kouji
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p. 117 - 124
(2007/10/02)
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- Herbicidal pyridine compounds
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Herbicidal 3- and/or 5-halogenomethyl-pyrid-2-yloxyphenoxy compounds and processes for making and using the same. Intermediates for making these compounds and their preparation are also disclosed. Thus, for example, 2-chloro-5-trichloromethylpyridine is prepared by a liquid phase chlorination of 3-methylpyridine under the influence of ultra violet light.
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- Processes for preparing 2-chloro-5-trifluoromethylpyridine
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One process comprises the step of reacting an amount of 5-carboxy-2-pyridone directly with both a suitable chlorinating agent and a suitable fluorinating agent to selectively transform both the 5-carboxy group and the 2-positioned oxygen function of the ring. A second process comprises the steps of reacting an amount of 5-carboxy-2-pyridone with a suitable fluorinating agent to selectively transform the 5-carboxy group without altering the 2-positioned oxygen function of the ring and reacting the 5-trifluoromethyl-2-pyridone thereby formed with a suitable chlorinating agent to cause 2-chloro-5-trifluoromethylpyridine to form. A third process comprises the steps of reacting an amount of a 5-carboxy-2-pyrone compound with a suitable fluorinating agent to selectively transform the 5-carboxy group without altering the 2-positioned oxygen function of the ring, reacting the 5-trifluoromethyl-2-pyrone compound thereby formed with an ammonia-containing agent in the presence of a caustic material to cause 5-trifluoromethyl-2-pyridone to form, and reacting the 5-trifluoromethyl-2-pyridone thereby formed with a suitable chlorinating agent to cause 2-chloro-5-trifluoromethylpyridine to form.
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- Process for producing chloro β-trifluoromethylpyridines
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A chloro β-trifluoromethylpyridine is produced by reacting a chloro β-trichloromethylpyridine with hydrogen fluoride in the presence of a specific metal fluoride in a vapor phase at high temperature for a short time. The chloro β-trifluoromethylpyridines which are useful as intermediates for agricultural chemicals and medicines can be obtained at high yield.
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- Process for preparing substituted pyridinyloxy ether intermediate
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A process for preparing pyridinyloxyphenols, useful intermediates in preparing pyridyloxyphenyl ether herbicides, in which a halopyridine is heated with hydroquinone in the absence of base and, optionally, in the absence of solvent.
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- Process for making 5-trifluoromethyl pyridone
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The chemical compound 5-trifluoromethyl-2-pyrone and a process for preparing a 5-trifluoromethyl-2-oxy compound of the formula STR1 wherein A is oxygen or nitrogen bearing a hydrogen, comprising the step of reacting an amount of the 5-carboxy precursor of the compound with a suitable fluorinating agent to selectively transform the 5-carboxy group without altering the oxygen function in the 2-position of the ring.
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- 2-Substituted-5-trifluoromethylpyridine compounds
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A 2-substituted-5-trifluoromethylpyridine compound represented by the following general formula (I): STR1 wherein X represents a hydrogen atom or a chlorine atom, and Y represents a fluorine atom or a chlorine atom, and a process for the preparation thereof.
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- 2-Phenoxy-5-trifluoromethylpyridine compounds and process for preparation thereof
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A 2-phenoxy-5-trifluoromethylpyridine compound represented by the following general formula (I): STR1 wherein X represents a hydrogen atom or a chlorine atom, and R represents a hydrogen atom or a cation, and a process for the preparation thereof.
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- Anti-inflammatory oxazole[4,5-b]pyridines
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The various isomers of oxazolo- and thiazolopyridines having utility as antiinflammatory, antipyretic and analgesic agents are prepared by condensation of an appropriate amino-hydroxypyridine or amino-mercaptopyridine with a carboxylic acid, halide or anhydride.
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