- HIGHLY FLUORINATED HETEROCYCLES. PART XVI. POLYFLUORINATED DERIVATIVES OF 1-METHYLPYRROLIDINE, 1-METHYLPYRROL-3-INE AND 1-METHYLPYRROLE
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Fluorination of 1-methylpyrrole with cobalt(III) fluoride gave six major products, 1-fluoromethyl- and 1-difluoromethyl- -octa-,-3H-hepta-, and -3H,4H-hexa-fluoropyrrolidine.Similar fluorination of 1-methyl-pyrrolidine gave better total recoveries of the same six products, together with 1-trifluoromethyloctafluoropyrrolidine, and 1-fluoromethyl- and 1-difluoromethyl- -2H-heptafluoropyrrolidine. 1-Fluoromethyl- and 1-difluoromethyl- -3H-heptafluoropyrrolidine each gave the corresponding polyfluoropyrrol-3-ine on dehydrofluorination with potassium hydroxide, but the 1-difluoromethyl-2H-heptafluoride could not be dehydrofluorinated. 1-Methyl- and 1-fluoromethyl- -3H,4H-hexafluoropyrrolidine similarly gave the corresponding 3H-3-ine, but no pyrrole.Reaction of 1-methyl-3H,4H-hexafluoropyrrolidine with 'old' aluminium chloride gave a little 1-methyl-2,5-dichlorodifluoropyrrole, the only fluoropyrrole we have obtained so far.Freshly sublimed AlCl3 afforded 1-methyltetrachloropyrrole (obtained also from 1-methylpyrrole and sulphuryl chloride) : fluorination of this with KCo(III)F4 gave 1-methyl- and 1-fluoromethyl- -3,4-dichloro-tetrafluoropyrrol-3-ine.
- Coe, Paul L.,Holton, Andrew G.,Sleigh, John H.,Smith, Peter,Tatlow, John Colin
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- Preparation method of fluorine-containing dicarboxylic acid
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The invention discloses a preparation method of fluorine-containing dicarboxylic acid, which comprises: by using fluorine-containing cycloolefin as a raw material, performing oxidation with an oxidantunder the actions of a solvent and a catalyst to generate the corresponding fluorine-containing dicarboxylic acid. According to the method, a mixed solvent composed of the organic solvent and water is used as a solvent system of an oxidation reaction, the fluorine-containing cycloolefin is oxidized into corresponding fluorine-containing dicarboxylic acid by using the oxidant under the action of the catalyst, and the method has the characteristics of simple operation, stable process, safety, short reaction time, high yield and high product quality, and is suitable for large-scale production.
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Paragraph 0035-0036; 0046
(2020/07/12)
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- Method for preparing fluorine-containing binary acyl fluoride from fluorine-containing cycloolefin
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The invention discloses a method for preparing fluorine-containing diacyl fluoride from fluorine-containing cycloolefin, which comprises the following steps: A) oxidizing fluorine-containing cycloolefin serving as a raw material by using an oxidant under the action of a solvent and a catalyst to generate corresponding fluorine-containing dicarboxylic acid; B) under the action of a solvent and a catalyst, subjecting the fluorine-containing dicarboxylic acid prepared in the step A and a fluorination reaction reagent to a fluorination reaction to obtain fluorine-containing diacyl fluoride. The method comprises the following steps: carrying out oxidation reaction on the fluorine-containing cycloolefin to generate corresponding fluorine-containing dicarboxylic acid; directly fluorinating the fluorine-containing dicarboxylic acid into the corresponding fluorine-containing binary acyl fluoride under the action of an organic solvent and a Lewis acid catalyst. The organic solvent and the specific catalyst are adopted, and other conditions are matched, so that the generation of the corresponding acyl fluoride with high efficiency and high yield from the fluorine-containing cycloolefin can beeffectively promoted.
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Paragraph 0054
(2020/07/13)
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- Production process of fluorine-containing carboxylic acid
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The invention discloses a production process of fluorine-containing carboxylic acid. The method comprises the following steps: by taking fluorine-containing olefin as a raw material, carrying out an oxidation reaction to obtain fluorine-containing carboxylate, reacting the fluorine-containing carboxylate with an acylating chlorination reagent to obtain a corresponding mixture of fluorine-containing acyl chloride and fluorine-containing acid anhydride, and hydrolyzing and drying the mixture of fluorine-containing acyl chloride and fluorine-containing acid anhydride to prepare the high-purity fluorine-containing carboxylic acid. The method provided by the invention is suitable for post-treatment of fluorine-containing carboxylic acid prepared by a fluorine-containing olefin (monoolefine, diene, cycloolefin and the like) oxidation method, replaces the traditional strong acid acidification and ether continuous extraction process, and is simpler, more convenient and more applicable; the purity of the fluorine-containing carboxylic acid prepared by the method can reach 98% or above.
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Paragraph 0029-0031; 0052
(2020/07/13)
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- Preparation method of fluorine-containing carboxylic acid
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The invention discloses a preparation method of fluorine-containing carboxylic acid. The method comprises the following steps: reacting fluorine-containing carboxylate used as a raw material with an acylating chlorination reagent to obtain a corresponding mixture of fluorine-containing acyl chloride and fluorine-containing anhydride, and hydrolyzing and drying the mixture of fluorine-containing acyl chloride and fluorine-containing anhydride to obtain high-purity fluorine-containing carboxylic acid. The method provided by the invention is suitable for post-treatment of fluorine-containing carboxylic acid prepared by a fluorine-containing olefin (monoolefine, diene, cycloolefin and the like) oxidation method, replaces the traditional strong acid acidification and ether continuous extractionprocess, and is simpler, more convenient and more applicable; and the method can also be used for recovering and purifying a fluorine-containing carboxylate emulsifier. The purity of the fluorine-containing carboxylic acid prepared by the method can reach 98% or above.
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Paragraph 0033; 0035-0036
(2020/07/12)
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- Method for synthesizing fluorochloro succinic acid
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The invention relates to a method for synthesizing fluorochloro succinic acid, and belongs to the field of organic chemical synthesis. The method for synthesizing fluorochloro succinic acid is characterized in that hexachlorobutadiene (the molecular formula is as follow: CCl2 being equal to CCl-CCl being equal to CCl2) generates fluorochloro cyclobutene (the molecular formula is as follow: Cyclo-C2FxCly-CCl being equal to CCl-, wherein the sum of the x and y is 4) under the effect of cyclo-fluorinated catalysts; then, the fluorochloro succinic acid (the molecular formula is HOOC-C2FxCly-COOH)is generated under the effect of oxidizing agents. CCl2 is equal to CCl-CCl being equal to CCl2 arrow Cyclo-C2FxCly-CCl being equal to CCl- arrow HOOC-C2FxCly-COOH. The method has the advantages thatthe raw materials are cheap; the resources can be conveniently obtained; the product separation and purification are simple; the industrial production is easy; three industrial wastes (waste water, waste solid and waste water) are few.
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Paragraph 0022-0027
(2018/04/03)
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- Radical-mediated degradation mechanisms of tribromo- and other trihalogenated acetic acids in oxygen-free solutions as studied by radiation chemistry methods
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.CBr2CO2- and .CCl2CO2- radicals, generated upon one electron reduction of tribromo- and trichloroacetic acids and .CF2CO2- radicals produced from difluoroacetic acid by reaction with .OH, exhibit optical absorptions in the UV with λmax at 290 nm (ε = 2580 dm3 mol-1 cim-1), 330 nm (ε = 3000 dm3 mol-1 cm-1) and 310 nm (ε ≈ 660 dm3 mol-1 cm-1), respectively. Mechanistically, the present report focuses on the free-radical-induced degradation of tribromoacetic acid. Absolute rate constants have been determined for the reactions of CBr3CO2- with eaq-, H., CO2. , .CH2OH, CH3.CHOH, (CH3)2.COH and .CH3 radicals to be k = 1.8 × 1010, 1.5 × 1010, 2.8 × 109, 1.6 × 109, 2.3 × 109, 3.0 × 109 and 3.0 × 107 dm3 mol-1 s-1, respectively. The major fate of .CBr2CO2- is self-termination to yield tetrabromosuccinic acid which, however, is unstable and thermally decomposes to HBr, CO2 and tribromoacrylic acid. Dibromofumaric acid, dibromomaleic acid and carbon monoxide were found as minor secondary products, formation of which is explained by a small yield of reductive decomposition of the transient tetrabromosuccinic acid. A complete and mechanistically satisfying material balance is provided for several systems in which CBr3CO2- has been degraded via a variety of radicals under various conditions. .OH Radicals do not react directly with CBr3CO2-. They have been shown, however, to contribute indirectly to the degradation of this acid via their reaction with reductively liberated bromide ions. The Br. atoms formed in this process are considered to abstract a bromine atom from CBr3CO2- or oxidize the carboxyl function in a one-electron transfer process. The formation of free Br. atoms has been recognized by pulse radiolysis through their conjugate dimer radical anions Br2.-. With respect to the other trihalogenated acids it is noteworthy that CCl3CO2- is efficiently reduced by CO2.- radicals and that CF3CO2- exhibits a high stability toward γ-irradiation and practically resists any reductive attack.
- Fliount, Roman,Makogon, Oksana,Guldi, Dirk M.,Asmus, Klaus-Dieter
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p. 1535 - 1545
(2007/10/03)
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- OXIDATION AND HYDROLYSIS OF METHYL PERFLUORO-5-OXA-6-HEPTENOATE
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In an aqueous medium in the presence of potassium persulfate or hydrogen peroxide methyl perfluoro-5-oxa-6-heptenoate is converted into perfluorosuccinic acid.Study of the reaction and the structure of the intermediate and final compounds made it possible to discover a multistage scheme for the transformation of methyl perfluoro-5-oxa-6-heptenoate with oxidation at the double bond followed by hydrolysis of the terminal groups.The transformation rate of methyl perfluoro-5-oxa-6-heptenoate at 60 deg C was determined.
- Chekmarev, P. M.,Makeeva, N. M.,Maksimov, V. L.,Popova, L. A.,Dreiman, N. A.
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p. 1879 - 1881
(2007/10/02)
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- ACYLATIONS OF PENTAFLUOROSULFANYLAMINE, SF5NH2. PART II. REACTIONS OF N-PENTAFLUOROSULFANYLCARBAMYLFLUORIDE, SF5NHC(O)F, AND N-PENTAFLUOROSULFANYLPERFLUOROSUCCINIMIDE,
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The carbamyl fluoride SF5NHC(O)F reacts with both H2O and H2S to give the urea (SF5NH)2CO.Evidence supports that this reaction proceeds through a mechanism involving dehydrofluorination; whereas, the reagents PhLi and PCl5 serve only to dehydrofluorinate SF5NHC(O)F.The ring of the cyclic imide can be readily opened by nucleophiles to give products such as SF5NHC(O)CF2CF2C(O)OH, SF5NHC(O)CF2CF2C(O)NH2, and SF5NHC(O)CF2CF2C(O)OCH3.Attempts to prepare analogous six- and seven-membered cyclic imides failed; however, mono- (SF5NHC(O)(CF2)3,4C(O)F) and disubstituted products (SF5NHC(O)(CF2)3,4C(O)NHSF5) were formed.The amide-acid fluorides are easily hydrolyzed by atmospheric moisture to the amide-acids SF5NHC(O)(CF2)3,4C(O)OH.
- Thrasher, Joseph S.,Howell, Jon L.,Clifford, Alan F.
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p. 431 - 442
(2007/10/02)
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- β-Substituted polyfluoropropionate salts and derivatives
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β-substituted polyfluoropropionate salts, derivatives and copolymers and processes for the preparation thereof.
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- An Azidopiperideine -> Dihydrodiazepine Ring Expansion of the Fluorocarbon Class: Synthesis of Perfluoro-(1,4-dimethyl-2,3-diazacyclohepta-1,3-diene) via Thermolysis of Perfluoro-(6-azido-2,6-dimethyl-1-azacyclohexene)
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Flow pyrolysis of perfluoro-(6-azido-2,6-dimethyl-1-azacyclohexene) at ca. 380 deg C and 1 mmHg yields perfluoro-(1,4-dimethyl-2,3-diazacyclohepta-1,3-diene) (mainly) plus its isomers perfluoro-(1,5-dimethyl-6,7-diazabicyclohept-6-ene) and perfluoro-(2,4-dimethyl-1,3-diazacyclohepta-1,3-diene); the molecular geometry of the first of these products has been determined by gas-phase electron diffraction methods.
- Abed-Rabboh, Mohammad,Banks, Ronald E.,Beagley, Brian
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p. 1117 - 1118
(2007/10/02)
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- OXYDATION ANODIQUE DE IODOPERFLUOROALCANES DANS LES ACIDES PERFLUOROALCANESULFONIQUES. PREPARATION DE NOUVEAUX ESTERS SULFONIQUES TOTALEMENT FLUORES RFSO3R'F A LONGUES CHAINES
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Perfluorinated sulphonic esters RFSO3R'F and fluorosulphates FSO3R'F, are easily obtained by anodic oxidation of iodoperfluoroalkanes R'FI in perfluoroalkene sulphonic acids RFSO3H (RF=CF3, C2F5, C4F9) and fluorosulphuric acid.With di-iodo compound I(CF2)4I, the mono and the diester can be selectively obtained.The alkaline hydrolysis of these esters produces perfluorinated carboxylic compounds.Polyfluorinated iodide R'FCH2CH2I are also oxidized in similar conditions.The mechanism of the electrolytic reaction is discussed.
- Germain, A.,Commeyras, A.
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p. 487 - 492
(2007/10/02)
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