359-35-3Relevant articles and documents
Synthesis and vibrational spectroscopy of 1,1,2,2-tetrafluoroethane and its13C2 and d2 isotopomers
Craig, Norman C.,Chuang, Jessica I.,Nwofor, Christiana C.,Oertel, Catherine M.
, p. 10092 - 10103 (2000)
The 13C2 and d2 isotopomers of 1,1,2,2-tetrafluoroethane (TFEA) have been synthesized. Raman spectra of these new species have been recorded, and infrared spectra of all three isotopomers, including some regions with high-resolution at -100°C, have also been recorded. Guided by recently published calculations of frequencies and infrared intensities and the new spectra, we have revised the previous assignments of fundamentals for the two rotamers of the normal species of TFEA. Assignments of the fundamentals for both rotamers of the 13C2 and d2 isotopomers are proposed. The anti rotamer is the more abundant species in the gas phase and, to a lesser extent, in the liquid phase and the only species in the crystal phase. Thus, the assignments of the anti rotamer of all three isotopic species are complete and supported by isotope product rules, but the assignments for the gauche rotamers are incomplete. Estimates of the missing frequencies for the gauche rotamer of the normal species are supplied.
Selective Copper Complex-Catalyzed Hydrodefluorination of Fluoroalkenes and Allyl Fluorides: A Tale of Two Mechanisms
Andrella, Nicholas O.,Xu, Nancy,Gabidullin, Bulat M.,Ehm, Christian,Baker, R. Tom
supporting information, p. 11506 - 11521 (2019/08/20)
The transition to more economically friendly small-chain fluorinated groups is leading to a resurgence in the synthesis and reactivity of fluoroalkenes. One versatile method to obtain a variety of commercially relevant hydrofluoroalkenes involves the catalytic hydrodefluorination (HDF) of fluoroalkenes using silanes. In this work it is shown that copper hydride complexes of tertiary phosphorus ligands (L) can be tuned to achieve selective multiple HDF of fluoroalkenes. In one example, HDF of the hexafluoropropene dimer affords a single isomer of heptafluoro-2-methylpentene in which five fluorines have been selectively replaced with hydrogens. DFT computational studies suggest a distinct HDF mechanisms for L2CuH (bidentate or bulky monodentate phosphines) and L3CuH (small cone angle monodentate phosphines) catalysts, allowing for stereocontrol of the HDF of trifluoroethylene.
Copper-Catalyzed Difluoromethylation of Aryl Iodides with (Difluoromethyl)zinc Reagent
Serizawa, Hiroki,Ishii, Koki,Aikawa, Kohsuke,Mikami, Koichi
supporting information, p. 3686 - 3689 (2016/08/16)
The combination of difluoroiodomethane and zinc dust or diethylzinc can readily lead to (difluoromethyl)zinc reagents. Therefore, the first copper-catalyzed difluoromethylation of aryl iodides with the zinc reagents is accomplished to afford the difluorom
Experimental and chemical kinetic study of the pyrolysis of trifluoroethane and the reaction of trifluoromethane with methane
Han, Wenfeng,Kennedy, Eric M.,Kundu, Sazal K.,MacKie, John C.,Adesina, Adesoji A.,Dlugogorski, Bogdan Z.
scheme or table, p. 751 - 760 (2010/09/04)
A detailed reaction mechanism is developed and used to model experimental data on the pyrolysis of CHF3 and the non-oxidative gas-phase reaction of CHF3 with CH4 in an alumina tube reactor at temperatures between 873 and 1173 K and at atmospheric pressure. It was found that CHF3 can be converted into C2F4 during pyrolysis and CH2=CF2 via reaction with CH4. Other products generated include C3F6, CH 2F2, C2H3F, C2HF 3, C2H6, C2H2 and CHF2CHF2. The rate of CHF3 decomposition can be expressed as 5.2×1013[s-1]e -295[kJmol-1]/RT. During the pyrolysis of CHF3 and in the reaction of CHF3 with CH4, the initial steps in the reaction involve the decomposition of CHF3 and subsequent formation of CF2 difluorocarbene radical and HF. It is proposed that CH4 is activated by a series of chain reactions, initiated by H radicals. The NIST HFC and GRI-Mech mechanisms, with minor modifications, are able to obtain satisfactory agreement between modelling results and experimental data. With these modelling analyses, the reactions leading to the formation of major and minor products are fully elucidated.
Investigation of CF2 carbene on the surface of activated charcoal in the synthesis of trifluoroiodomethane via vapor-phase catalytic reaction
Yang, Guang-Cheng,Lei, Shi,Pan, Ren-Ming,Quan, Heng-Dao
experimental part, p. 231 - 235 (2009/08/07)
This paper investigates the synthetic mechanism of trifluoroiodomethane (CF3I) in the reaction of trifluoromethane and iodine via vapor-phase catalytic reaction. It is suggested that CF2 carbene is the key intermediate and is formed in the pyrolysis process of CHF3 at high temperature. However, in pyrolysis of CHF3 under activated charcoal (AC) existing conditions, no C2F4 was detected. H2 and 2-methyl-2-butene could not trap the CF2 carbene. When treating the remained compounds on the used AC with H2, CH4 is formed on the process. It is proposed that CF2 carbene combines with AC strongly and transfers into CF3 radical on heat. In addition, it is found that the AC is not only the catalyst supporter to form CF3I, but also a co-catalyst to promote the formation of CF2 carbene and CF3 radical.
The preparation of HCF2CdX and HCF2ZnX via direct insertion into the carbon halogen bond of CF2HY (Y = Br, I)
Burton, Donald J.,Hartgraves, Greg A.
, p. 1198 - 1215 (2008/02/08)
The difluoromethylcadmium and zinc reagents have been prepared in DMF via direct insertion of Cd0 into the carbon halogen bond of CF2HY (Y = Br, I). These reagents are stable at 65-75 °C and exhibit prolonged stability and activity at room temperature. Metathesis of the difluoromethylcadmium reagents with Cu(I)X (X = Br, Cl) at -55 °C rapidly produces difluoromethylcopper. The copper reagent is significantly less stable than the cadmium or zinc reagent and rapidly decomposes at room temperature. The difluoromethylcadmium and copper reagents exhibit good reactivity with allylic halides, propargylic derivatives and 1-iodoalkynes to provide good yields of the corresponding difluoromethylalkenes, difluoromethylallenes and difluoromethyl-2-alkynes. Alkylation is successful only with reactive alkyl halides. Generally, the difluoromethylcopper reagent is more reactive than the difluoromethylcadmium reagent and generally exhibits higher regioselectivity in reactions that can occur by either α- or γ-attack.
PROCESS FOR PRODUCTION OF 1,1,1,2-TETRAFLUOROETHANE AND/OR PENTAFLUOROETHANE AND APPLICATIONS OF THE SAME
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Page/Page column 10-16, (2008/06/13)
A process for producing high purity 1,1,1,2-tetrafluoroethane and/or pentafluoroethane by the step of purifying a crude product obtained by reacting trichloroethylene and/or tetrachloroethylene with hydrogen fluoride comprised of a main product including 1,1,1,2-tetrafluoroethane and/or pentafluoroethane, hydrogen fluoride as an azeotropic component with the main product, and impurity ingredients including at least an unsaturated compound, wherein said purifying step includes a step of bringing a mixture obtained by newly adding hydrogen fluoride into said crude product into contact with a fluorination catalyst in the vapor phase to reducing the content of the unsaturated compound contained in said crude product and a distillation step.
Gas-phase fluorination of fluoroethanes with elemental fluorine
Pashkevich,Mukhortov,Alekseev,Asovich,Rozhdestvenskaya
, p. 1151 - 1155 (2007/10/03)
Scientific basis for industrial gas-phase fluorination of fluoroethanes with elemental fluorine allowing production of higher-fluorinated fluoroethanes from lower-fluorinated compounds is developed. 2001 MAIK "Nauka/Interperiodica".
Pyrolyses of chlorodifluoromethane and trifluoromethane in the presence of hydrogen. Mechanism and optimization of reaction conditions
Romelaer,Kruger,Baker,Dolbier Jr.
, p. 6767 - 6772 (2007/10/03)
When CHC1F2 and CHF3 are subjected to high-temperature, gas-phase flow pyrolysis in the presence of H2, they are converted, via a free radical chain mechanism, to CH2F2, CHF2CHF2, and CF3CH2F in good yield. Optimal conditions for pyrolysis of CHC1F2 involve a high conversion (92%) at 650 °C with an observed yield of products = 18, 17, and 28%, respectively, whereas optimal conditions for CHF3 involve a low conversion (24%) at 775 °C, but a higher yield of products (26, 6, and 39%, respectively).
Gas-phase kinetics of the self reactions of the radicals CH2F and CHF2
Beiderhase, Thomas,Hack, Walter,Hoyermann, Karlheinz,Olzmann, Matthias
, p. 625 - 641 (2007/10/03)
Fluorinated hydrocarbon radical-radical reactions in the gas phase have been studied at low pressure (0.5 ≤ p/mbar ≤ 2) and low temperature (253 ≤ T/K ≤ 333) using the discharge flow reactor molecular beam sampling mass spectrometry (MS) technique. Stable
