- Synthesis of 1,2-diiodotetrafluoroethane with pyrolysis gas of waste polytetrafluoroethylene as raw material
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In the present study, waste polytetrafluoroethylene (PTFE) is recycled to generate the monomer tetrafluoroethylene by pyrolysis in vacuum condition. The reaction parameters are investigated; under 500-550°C and 2 kPa, the yields of tetrafluoroethylene can reach 95%. Then the pyrolysis gas is applied without separation as reactant together with iodine to synthesize 1,2- diiodotetrafluoroethane, which is the key intermediate for synthesis of many fluorine-containing compounds. Under the optimal conditions, temperature 150-160°C, pressure 12 atm and ratio of solvent to iodine 0.5-0.6, the conversion of iodine can rise up to 98%. The method of this paper uses waste polytetrafluoroethylene (PTFE) as raw material, which is environmental benign and helpful to prevent white pollution.
- Jing, Zhu,Baohe, Wang,Dongzhi, Liu
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Read Online
- Fluorine-containing compound, and its manufacturing method (by machine translation)
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PROBLEM TO BE SOLVED: perfluoroalkyl group CF2 groups of 4, 5 or 6 of this compound, a water and oil repellent, mold release agent and an active component of a surface treatment such as a resin or elastomer-like shaped when manufacturing a fluorine-containing polymer, which is effectively used as a polymerizable monomer, a fluorine-containing compound, and a manufacturing method thereof. SOLUTION: the [...]fluorine, vinylidene fluoride n under heating in the presence of or after the reaction, the reaction of a basic compound, fluorine-containing olefin compound is used. Selected drawing: no (by machine translation)
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Paragraph 0038; 0039
(2017/01/02)
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- PROCESS FOR THE PURIFICATION OF ALPHA, OMEGA-DIIODOPERFLUORINATED COMPOUNDS
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The invention concerns a process for purifying α,ω-diiodoperfluorinated compounds of formula 1-(CF2CF2Y)m—I comprising contacting an impure α,ω-diiodoperfluorinated compound with a suitable sequestering agent, with formation of a reversible adduct and separating the α,ω-diiodoperfluorinated compound from the adduct itself. Diammonium dihalogenids of the general formula [R1,2,3N—(CH2)n—NR4,5,6]2*2X (R1-6=alkyl C1-C6n=8-26, X═I, Br, Cl) also called ‘methonium compounds’ are the preferred sequestering agents.
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Page/Page column 4-5
(2010/08/08)
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- PROCESS FOR THE PURIFICATION OF ALPHA,OMEGA-DIIODOPERFLUORINATED COMPOUNDS
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The invention concerns a process for purifying α,ω-diiodoperfluorinated compounds of formula I-(CF2CF2Y)m-I comprising contacting an impure α,ω-diiodoperfluorinated compound with a suitable sequestering agent, with formation of a reversible adduct and separating the α,ω-diiodoperfluorinated compound from the adduct itself. The invention also concerns α,ω-diiodoperfluorinated compounds of formula I-(CF2CF2Y)m-I wherein m is 5 to 10 and having 100% purity grades.
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Page/Page column 8-11; 20
(2009/03/07)
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- Process for manufacturing diiodoperfluoroalkanes
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The present invention involves a process for the manufacture of α,ω-diiodoperfluoroalkanes of the formula I ― (CF2CF2)n ― I, wherein n is an integer between 2 and 6. The latter compounds are produced at relatively high conversions and under relatively mild reaction temperatures and pressures, compared to prior art processes, by the elimination of the gaseous byproduct perfluorocyclobutane throughout the process.
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Page column 3
(2008/06/13)
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- Environmentally Benign Processes for Making Useful Fluorocarbons: Nickel- or Copper(I) Iodide-Catalyzed Reaction of Highly Fluorinated Epoxides with Halogens in the Absence of Solvent and Thermal Addition of CF2I 2 to Olefins
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Highly fluorinated epoxides react with halogens in the presence of nickel powder or CuI at elevated temperatures to provide a useful and general synthesis of dihalodifluoromethanes (CF2X2) and fluoroacyl fluorides (RFCOF) in the absence of solvent. At 185 °C, hexafluoropropylene oxide and halogens produce CF2X 2 (X = I, Br) in 68-90% isolated yields, along with small amounts of X(CF2)nX, (n = 2, 3). With interhalogens I-X (X = Cl, Br), a mixture of CF2I2, CF2XI, and CF 2X2 was obtained. The fluorinated epoxides substituted with perfluorophenyl, fluorosulfonyl, and chlorofluoroalkyl groups also react cleanly with iodine to give CF2I2 and the corresponding fluorinated acyl fluorides in good yields. The reaction probably involves an oxidative addition of fluorinated epoxides into metal surfaces to form an oxametallacycle, followed by rapid decomposition to difluorocarbene-metal surfaces, which alters the reactivity of the difluorocarbene carbon from electrophilic to nucleophilic. The increase of nucleophilicity of difluorocarbene facilitates the reaction with electrophilic halogens. CF 2I2 reacted with olefins thermally to give 1,3-diiodofluoropropane derivatives. Both fluorinated and nonfluorinated alkenes gave good yields of the adducts. Reaction with ethylene, propylene, perfluoroalkylethylene, vinylidene fluoride, and trifluoroethylene provided the corresponding adducts in 58-86% yields. With tetrafluoroethylene, a 1:1 adduct was predominantly formed along with small amounts of higher homologues. In contrast to perfluoroalkyl iodides, CF2I2 also readily adds to perfluorovinyl ethers to give 1,3-diiodoperfluoro ethers.
- Yang, Zhen-Yu
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p. 2394 - 2403
(2007/10/03)
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- A facile preparation of ICF2CF2I and its reaction with ethylene
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A facile preparation of ICF2CF2I in high yield is carried out using a halogen lamp. In a similar manner, ICF2CF2I reacts with ethylene to give ICH2CH2CF2CF2CH2CH2I.
- Renn, Julie A.,Toney, Aimee D.,Terjeson, Robin J.,Gard, Gary L.
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p. 113 - 114
(2007/10/03)
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- Facile conversion of perfluoroacyl fluorides into other acyl halides
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Nine perfluoroacyl fluorides underwent halogen exchange when treated with anhydrous lithium halides to give acyl chlorides, bromides and iodides in high yields. The temperature dependence of this reaction is described. In the reaction with perfluorodiacyl fluoride, the diacyl halides possessing different acyl halide-groups were also produced. Of the alkaline metal salts used halogen exchange was successful only with lithium salts because of the interaction between lithium and fluorine.
- Fukaya, Haruhiko,Matsumoto, Tomonori,Hayashi, Eiji,Hayakawa, Yoshio,Abe, Takashi
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p. 915 - 920
(2007/10/03)
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- Polyfluoroalkyl Polyfluorovinyl Ethers. II. Synthesis of Perfluoro(cyclohexylmethyl) Perfluorovinyl Ether
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Perfluoro(cyclohexylmethyl) perfluorovinyl ether was prepared by two methods: dehalogenation of perfluoro(cyclohexylmethyl) 2-iodotetrafluoroethyl ether and condensation of perfluorocyclohexylcarbonyl fluoride with perfluoropropene oxide, followed by thermolysis of the condensation product.
- Yuminov, V. S.
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p. 1040 - 1043
(2007/10/03)
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- RELATIONSHIPS IN THE IODOFLUORINATION OF FLUOROOLEFINS IN THE IODINE-IODINE PENTAFLUORIDE-METAL FLUORIDE SYSTEM
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On the basis of the results from investigation of the reaction of fluoroolefins with the components of the iodine-iodine pentafluoride-metal fluoride iodofluorinating system and kinetic and spectroscopic investigations a mechanism is proposed for the iodofluorination of fluoroolefins as the conjugate addition of iodine and fluorine with initial electrophilic attack on the multiple bond by the I2+ cation.The role of mass exchange during synthesis in a flow-type system is noted.
- Morozov, A. V.,Maksimov, B. N.
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p. 1224 - 1229
(2007/10/03)
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- TELOMERIZATION OF TETRAFLUOROETHYLENE AND HEXAFLUOROPROPENE: SYNTHESIS OF DIIODOPERFLUOROALKANES
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Linear diiodoperfluoroalkanes are easily synthesized by thermal telomerization of tetrafluoroethylene with iodine.When hexafluoropropene reacts with I(C2F4)nI n = 2,3,4 as telogen, new diiodocompounds of formula I(C3F6)m(C2F4)n(C3F6)pI n = 2,3,4 m = 0,1,2 p = 1,2 are obtained.In both cases there are high yields, based both on iodine and on olefin.
- Tortelli, V.,Tonelli, C.
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p. 199 - 217
(2007/10/02)
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- A Convenient One-Stage Synthesis of Some Diiodoperfluoroalkanes By Using Tetrafluoroethylene Derived From Poly(tetrafluoroethylene) Waste
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Tetrafluoroethylene was prepared by a thermal depolymerization of poly(tetrafluoroethylene) waste.The gaseous mixture containing 95-97percent tetrafluoroethylene has been used without further purification in a direct reaction with iodine to synthesize some α,ο-diidoperfluoroalkenes at temperature 285+/-5 deg C for 8 h.Stoichiometric one to one ratio of the reagents has been found to produce higher diidoperfluoroalkenes yield per unit reaction volume than synthesis in the presence of an excess of tetrafluoroethylene.This approach provides a rapid one-pot procedure to these valuable reagents without any dangerous step.
- Kotov, Stefan V.,Ivanov, Georgi D.,Kostov, Georgi K.
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p. 293 - 296
(2007/10/02)
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- PERFLUORO-ω-IODO-3-OXAALKANESULFONYL FLUORIDES AS INTERMEDIATES FOR SURFACTANTS AND VINYL COMPOUNDS
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Fluorosulfonyldifluoroacetyl fluoride (FOCCF2SO2F) quantitatively formed from sulfur trioxide and TFE through tetrafluoroethanesultone, has been converted into the octafluoro-5-iodo-3-oxapentanesulfonyl fluoride (ICF2CF2OCF2CF2SO2F) by the well known reaction involving MF, iodine and TFE in aprotic solvents.The iodo compound allowed us to obtain TFE telomers having both fluorosulfonyl and iodo terminal groups.These telomers were easily converted into the surfactants CF3CF2(CF2CF2)nOCF2F2SO3M by fluorination, and into the vinyl derivatives CF2=CF(CF2CF2)nOCF2CF2SO2F by dehalogenation.The scope of this study was to illustrate new methods for the synthesis of perfluoroalkane and perfluoroalkene sulfonates.
- Bargigia, G. A.,Caporiccio, G.,Pianca, M.
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p. 403 - 410
(2007/10/02)
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