- Gas phase process for chlorotrifluoroethylene
-
Disclosed are processes for the dechlorination of haloethanes comprising reacting in the gaseous phase a haloethane and reducing agent such as an alkene, an alkane, hydrogen or combinations of two or more of these, in the presence of a silicon-based catalyst.
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Page/Page column 12; 17
(2020/07/15)
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- GAS PHASE PROCESS FOR CHLOROTRIFLUOROETHYLENE
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The present invention relates to a process for the preparation of haloethylenes, and preferably perhaloethylenes, by the gas-phase dechlorination of haloethanes in the presence of a catalyst and optionally in the presence of an alkene or an alkane. In particular aspects, the invention relates to a gas-phase process for preparing chlorotrifluoroethylene (CTFE). More particularly, the present invention relates to a gas-phase process for preparing CTFE from 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) by dechlorination in the presence of an alkene or an alkane and a catalyst.
- -
-
Paragraph 0117-0120
(2019/08/20)
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- PROCESS FOR PRODUCING CHLOROTRIFLUOROETHYLENE
-
The present invention relates, at least in part, to a process for making chlorotrifluoroethylene (CFO-1113) from 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a). In certain aspects, the process includes dehydrochlorinating 1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a) in the presence of a catalyst selected from the group consisting of (i) one or more metal halides; (ii) one or more halogenated metal oxides; (iii) one or more zero-valent metals or metal alloys; (iv) combinations thereof.
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Page/Page column 11; 12
(2016/03/19)
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- At the same time, preparation of trifluoro-vinyl chloride and tetrafluoroethylene, and method
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The invention discloses a method for simultaneously preparing trifluorochloroethylene and tetrafluoroethylene. The method comprises the following steps: mixing monochlorodifluoromethane, dichlorofluoromethane and a diluent, performing copyrolysis reaction to generate pyrolysis gas, quickly cooling, washing by water and alkali in sequence, drying, compressing, rectifying and purifying to obtain trifluorochloroethylene and tetrafluoroethylene, wherein the molar ratio of monochlorodifluoromethane to dichlorofluoromethane is 1 to (1-4), the molar ratio of the diluent to the total amount of monochlorodifluoromethane and dichlorofluoromethane is 1 to (1-20), the reaction temperature is 500-1,200 DEG C, the reaction pressure is 0.1-1MPa, and the reaction retention time is 0.01-10 seconds. The method has the advantages of being simple in process, easy for industrialization and environment-friendly, and raw materials are easily available.
- -
-
Paragraph 0054; 0055
(2017/03/22)
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- Novel green chlorotrifluoroethylene preparation method
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A process for preparing trifluorochloroethylene including: in a multi-tubular reactor, hydrogenation reacting 1,1,2-trifluoro-1,2,2-trichloroethane directly with a catalyst potassium zinc trihydride to obtain trifluorochloroethylene, wherein the catalytic reaction is performed at a temperature of 250-350° C. and a pressure of 0.7-1.0 MPa for 10-20 seconds. The conventional process in which zinc powder is used for dechlorination or hydrogen is used for dechlorination through hydrogenation with the action of a noble metal catalyst is avoided in the process disclosed herein. The present process substantially reduces the production cost of trifluorochloroethylene, and substantially increases the product yield, which can be up to 99% or more.
- -
-
Paragraph 0022; 0023
(2017/03/17)
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- Redox-active porous coordination polymers prepared by trinuclear heterometallic pivalate linking with the redox-active nickel(II) complex: Synthesis, structure, magnetic and redox properties, and electrocatalytic activity in organic compound dehalogenation in heterogeneous medium
-
Linking of the trinuclear pivalate fragment Fe2CoO(Piv) 6 by the redox-active bridge Ni(L)2 (compound 1; LH is Schiff base from hydrazide of 4-pyridinecarboxylic acid and 2- pyridinecarbaldehyde, Piv- = pivalate) led to formation of a new porous coordination polymer (PCP) {Fe2CoO(Piv)6}{Ni(L) 2}1.5 (2). X-ray structures of 1 and 2 were determined. A crystal lattice of compound 2 is built from stacked 2D layers; the Ni(L) 2 units can be considered as bridges, which bind two Fe 2CoO(Piv)6 units. In desolvated form, 2 possesses a porous crystal lattice (SBET = 50 m2 g-1, V DR = 0.017 cm3 g-1 estimated from N2 sorption at 78 K). At 298 K, 2 absorbed a significant quantity of methanol (up to 0.3 cm3 g-1) and chloroform. Temperature dependence of molar magnetic susceptibility of 2 could be fitted as superposition of X MT of Fe2CoO(Piv)6 and Ni(L)2 units, possible interactions between them were taken into account using molecular field model. In turn, magnetic properties of the Fe2CoO(Piv) 6 unit were fitted using two models, one of which directly took into account a spin-orbit coupling of CoII, and in the second model the spin-orbit coupling of CoII was approximated as zero-field splitting. Electrochemical and electrocatalytic properties of 2 were studied by cyclic voltammetry in suspension and compared with electrochemical and electrocatalytic properties of a soluble analogue 1. A catalytic effect was determined by analysis of the catalytic current dependency on concentrations of the substrate. Compound 1 possessed electrocatalytic activity in organic halide dehalogenation, and such activity was preserved for the Ni(L)2 units, incorporated into the framework of 2. In addition, a new property occurred in the case of 2: the catalytic activity of PCP depended on its sorption capacity with respect to the substrate. In contrast to homogeneous catalysts, usage of solid PCPs may allow selectivity due to porous structure and simplify separation of product.
- Lytvynenko,Kolotilov,Kiskin,Cador,Golhen,Aleksandrov,Mishura,Titov,Ouahab,Eremenko,Novotortsev
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supporting information
p. 4970 - 4979
(2014/06/09)
-
- Catalytic synthesis of polyfluoroolefins
-
A catalytic synthesis of polyfluoroolefins was developed proceeding from polyfluorochlorocarbons with the use of industrially produced nickel-chromium catalyst. Three ways of the catalytic synthesis of fluoroolefins were implemented: the cleavage of vicinal chlorine atoms from polyfluorochlorocarbons, the replacement of vinyl chlorine atoms by hydrogen in fluorochloroolrfins, and the reductive dimerization of polyfluorochlorocarbons containing a trichloromethyl group. The condition of a prolonged operation of the nickel-chromium catalyst was found consisting in the application of quartz for absorption of the hydrogen fluoride formed as a side product.
- Stepanov,Delyagina,Cherstkov
-
scheme or table
p. 1290 - 1295
(2011/01/04)
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- SYSTEMS AND PROCESSES FOR CFO-1113 FORMATION FROM HCFC-123a
-
Systems and processes relating to the formation and production of CFO-1113 HCFC-123a. Such systems and processes can include one or more reactors in series that react HCFC-123a and base to produce reaction product vapors including CFO-1113. Optionally, a phase transfer agent or catalyst can be added to the reaction to enhance the reaction rate. The CFO-1113 can be separated from the reaction product vapors to produce a CFO-1113 product stream. The reactions can be conducted continuously, and a liquid effluent stream can be removed from the reactors during the reaction. Unreacted HCFC-123a can be separated from the liquid effluent stream and provided back to the reactors.
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Page/Page column 4
(2010/12/31)
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- GASEOUS DIELECTRICS WITH LOW GLOBAL WARMING POTENTIALS
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A dielectric gaseous compound which exhibits the following properties: a boiling point in the range between about ?20° C. to about ?273° C.; non-ozone depleting; a GWP less than about 22,200; chemical stability, as measured by a negative standard enthalpy of formation (dHf0); a toxicity level such that when the dielectric gas leaks, the effective diluted concentration does not exceed its PEL; and a dielectric strength greater than air.
- -
-
-
- PROCESS FOR MAKING CHLOROTRIFLUOROETHYLENE FROM 1,1,2-TRICHLOROTRIFLUOROETHANE
-
A process for the making chlorotrifluoroethylene. The process has the step of reacting 1,1,2-trichlorotrifluoroethane with a reducing metal in the presence of a polar aprotic solvent under conditions sufficient to form chlorotrifluoroethylene.
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Page/Page column 2
(2010/03/02)
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- PROCESS FOR THE PREPARATION OF HALO-OLEFINS
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Described is a process for preparing a halo-olefin comprising contacting a halogenated hydrocarbon with a metal dehalogenating agent, in a solvent, in the presence of a phase transfer catalyst, under conditions sufficient to dehalogenate said halogenated hydrocarbon to produce a product stream comprising said halo-olefin. In one embodiment, the halogenated hydrocarbon is trifluorotrichloroethane and the halo-olefin is chlorotrifluoroethylene.
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Page/Page column 3
(2010/11/03)
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- Coupling reactions of chlorofluoro and perfluoroalkyl iodides
-
Coupling reactions of chlorofluoro- and perfluoroalkyl iodides R f-I with Rf = ClCF2CFCl-(CF2) 3CF2-, ClCF2CFClO(CF2) 3CF2-, ClCF2CFCl-, (CF3) 2CF- , (CF3)2CFCF2CF2- in the presence of a zinc/solvent system give dimers in good yields. Both homodimerizations (one iodide) and heterodimerizations (two different iodides) have been studied. The effect of temperature and solvent is shown. The zinc mediated dechlorination of vicinal chlorine atoms in the dimers afforded terminal alkenes and dienes.
- Wlassics, Ivan,Tortelli, Vito
-
scheme or table
p. 1719 - 1728
(2009/06/05)
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- Synthesis of pentafluorosulfanyl trifluorovinyl ether and its facile rearrangement to difluoro(pentafluorosulfanyl)acetyl fluoride
-
A radical departure: A novel fluorinated vinyl ether 1 was synthesized and was found to undergo an unexpected facile rearrangement to give compound 2, which was confirmed to be a radical process by EPR spectroscopy. (Chemical Equation Presented).
- Du, Libin,Elliott, Bevan,Echegoyen, Luis,DesMarteau, Darryl D.
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p. 6626 - 6628
(2008/09/17)
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- PROCESS FOR PRODUCTION OF 1,1,1,2-TETRAFLUOROETHANE AND/OR PENTAFLUOROETHANE AND APPLICATIONS OF THE SAME
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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.
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Page/Page column 11; 16
(2008/06/13)
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- Synthesis of 1,2,3,4-tetrachlorohexafluorobutane
-
The condensation of 1-iodo-1,2,2-trifluoro-1,2-dichloroethane induced by granulated Zn in the presence of catalytic amounts of AcOEt without a solvent results in 1,2,3,4-tetrachlorohexafluorobutane in high yield.
- Karimova,Glazkov,Ignatenko,Mysova
-
p. 2336 - 2337
(2007/10/03)
-
- Preparation of 1-X-2,2-Difluoroethenylxenon(II) Tetrafluoroborates [CF 2=CXXe][BF4]
-
The new type of alkenylxenon(II) salts [CF2=CXXe] [BF 4] (X = H, Cl, CF3) was prepared by reacting the corresponding alkenyldifluoroboranes CF2=CXBF2 with XeF2 in 1,1,1,3,3-pentafluoropropa
- Frohn, Hermann-Josef,Bardin, Vadim V.
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p. 2465 - 2469
(2008/10/09)
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- Method of preparing fluoroaromatic compounds
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The present invention provides a method of preparing ortho-difluorobenzene derivatives, which comprises (a) providing a mixture of cyclohexenes by reacting chlorotrifluoroethylene (CTFE) and 1,3-diene in a flow reactor and distilling the resultant, and (b) dehydrohalogenating the mixture of cyclohexenes with a phase transition catalyst in the presence of alkali metal hydroxide at temperature range of 40 to 150 °C without using any organic solvent. The distillate having low boiling point, which is obtained during distillation of the resultant, is recycled into the flow reactor. The present invention also provides a method of preparing 2-chloro-4,5-difluorobenzoic acid, which comprises (a) providing a mixture of 4-chloro-1-methyl-4,5,5-trifluorocyclohexene and 5-chloro-1-methyl-4,4,5-trifluorocyclohexene by reacting chlorotrifluoroethylene (CTFE) and isoprene and distilling the resultant, (b) dehydrohalogenating said mixture in the presence of alkali metal hydroxide and a phase transition catalyst to form 3,4-difluorotoluene, (c) reacting said 3,4-difluorotoluene with chlorine gas without using any organic solvent to form 2-chloro-4,5-difluorotoluene, (d) photo-reacting said 2-chloro-4,5-difluorotoluene with chlorine gas under a lighting mercury lamp without using any organic solvent to form 2-chloro-4,5-difluorobenzotrichloride, and (e) reacting said 2-chloro-4,5-difluorobenzotrichloride with aqueous acid solution without using any organic solvent. The present invention also provides a method of preparing 2-chloro-4,5-difluorobenzoyl chloride by reacting the 2-chloro-4,5-difluorobenzotrichloride of step (e) above with zinc oxide.
- -
-
-
- Synthesis and Diels-Alder cycloaddition reactions of [(2,2-dichloro-1- fluoroethenyl)sulfinyl] benzene and [(2-chloro-1,2-difluoro ethenyl)sulfinyl] benzene
-
Synthesis of [(2,2-dichloro-1-fluoroethenyl)sulfinyl] benzene and [(2- chloro-1,2-difluoro ethenyl)sulfinyl] benzene and their Dieis-Alder cycloadditions with cyclopentadiene, furan and 1,3-diphenylisobenzofuran under thermal and microwave irradiation conditions are described. 2000 Elsevier Science Ltd.
- Sridhar, Madabhushi,Leela Krishna,Madhusudana Rao, Jampani
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p. 3539 - 3545
(2007/10/03)
-
- Method of preparing fluoroaromatic compounds
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The present invention provides a method of preparing ortho-difluorobenzene derivatives, which comprises (a) providing a mixture of cyclohexenes by reacting chlorotrifluoroethylene (CTFE) and 1.3-diene in a flow reactor and distilling the resultant, and (b) dehydrohalogenating the mixture of cyclohexenes with a phase transition catalyst in :he presence of alkali metal hydroxide at temperature range of 40 to 150° C. without using any organic solvent. The distillate having low boiling point, which is obtained during distillation of the resultant, is recycled into the flow reactor. The present invention also provides a method of preparing 2-chloro-4,5-difluorobenzoic acid, which comprises (a) providing a mixture of 4-chloro-1-methyl-4,5,5-trifluorocyclohexene and 5-chloro-1-methyl-4,4,5-trifluorocyclohexene by reacting chlorotrifluoroethylene (CTFE) and isoprene and distilling the resultant. (b) dehydrohalogenating said mixture in the presence of alkali metal hydroxide and a phase transition catalyst to form 3,4-difluorotoluene, to reacting said 3,4-difluorotoluene with chlorine gas without using any organic solvent to form 2-chloro-4,5-difluorotoluene, (d) photo-reacting said 2-chloro-4,5-difluorotoluene with chlorine gas under a lighting mercury lamp without using any organic solvent to form 2-chloro-4,5-difluorobenzotrichloride, and (e) reacting said 2-chloro-4,5-difluorobenzotrichloride with aqueous acid solution without using any organic solvent. The present invention also provides a method of preparing 2-chloro-4,5-difluorobenzoyl chloride by reacting the 2-chloro-4,5-difluorobenzotrichloride of step (e) above with zinc oxide.
- -
-
-
- CO2 laser induced IRMPD of 2-bromo-2-chloro-1,1,1 -trifluoroethane: Time-resolved luminescence studies
-
The IRMPD of 2-bromo-2-chloro-1,1,1-trifluoroethane gives rise to an intense visible light emission between 350 and 750 nm due to various carbenes. The effect of various experimental parameters such as laser energy, pulse duration and substrate pressure on the emission has been studied. Infrared fluorescence studies have also been carried out to explore the vibrational excitation of the photoproducts. A self-consistent mechanism is proposed explaining the complex photodissociation dynamics of the system.
- Pushpa,Kumar, Awadhesh,Vatsa,Naik,Annaji Rao,Mittal,Parthasarathy,Sarkar
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p. 167 - 173
(2007/10/03)
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- A new telogen for telechelic oligomers of chlorotrifluoroethylene
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Elemental iodine is slightly soluble in liquid chlorotrifluoroethylene (CTFE) under autogenous pressure at room temperature.Exposure of a mixture of no more than 0.22 mol of iodine with 1 mol of CTFE in a borosilicate glass Carius tube to sunlight, an artificial UV source or to γ-radiation resulted in complete conversion of all the solid iodine initially to ICF2CFClI (1), which was isolated and characterised.The reaction is reversible, the equilibrium constant for I2 + CTFEliq ->/- 1 being ca. 0.22.Thus with light or heat, isolated unconfined 1 reverted to iodine and CTFE.Additional irradiation of 1 confined with excess liquid CTFE led to the irreversible formation of telomers I(CF2CFCl)nI (2).The average value of n in the distribution of telomers increased with dose giving liquids (n = 2-4) or greases (n = 2-10) which were much more stable than 1.Upon bromination, individual telomers in the series Br(CF2CFCl)nBr were isolated and characterised. - Keywords: Telogens; Telechelic oligomers; Chlorotrifluoroethylene; NMR spectroscopy; Mass spectrometry; IR spectroscopy
- Chambers, Richard D.,Greenhall, Martin P.,Wright, Anthony P.,Caporiccio, Gerardo
-
-
- THERMAL AND THERMOOXIDATIVE STABILITY OF OZONE-SAFE FREONS
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The thermal stability of freons 134-a (CF3CH2F), 134 (CHF2CHF2), and 133-a (CF3CH2Cl) was studied experimentally by the pulsed adiabatic compression method.The conversion of the freons, beginning at a value of 0.0002, was determined from the carbon balance of the reaction products, calculated from the chromatographic data.The Arrhenius expressions for the total rate constants of thermal decomposition of the freons are presented.The intermediates of the thermal transformations of the freons were recorded by kinetic spectroscopy in the ultraviolet and visible regions.The UV spectrum of the carbene :CHCF3 with characteristic absorption maxima at λ 235 and 430 nm is described for the first time.
- Buravtsev, N. N.,Grigor'ev, A. S.,Kolbanovskii, Yu. A.,Ovsyannikov, A. A.
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p. 1880 - 1890
(2007/10/03)
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- KINETICS OF THERMAL DECOMPOSITION OF 1,1,2-TRIFLUORO-1,2-DICHLOROETHANE
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Kinetics of thermal decomposition of 1,1,2-trifluoro-1,2-dichloroethane has been studied in a flow system in the temperature range from 930 to 986 K.The rate constant was calculated.Mechanism of the first-order homogeneous reaction has been proposed.
- Nikolaev, A. A.,Goncharov, E. P.,Karpova, N. E.,Skripnichenko, E. N.,Barabanov, V. G.
-
-
- INVESTIGATIONS IN THE REGION OF INDUSTRIAL FLUORINATED COMPOUNDS
-
The synthesis and properties of ozone-friendly fluorohydrocarbons, fluoroolefins, and fluorinated compounds with functional groups (acids, alcohols, esters, and others), used for the creation of effective surfactants, ion-exchange membranes for various purposes, heat-resistant oils, and greases, were investigated.A technology was developed for the production of highly pure fluorinated compounds for microelectronics, fiber optics, and medicine.
- Maksimov, B. N.
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p. 1935 - 1940
(2007/10/03)
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- Process for the purification of chlorofluorohydrocarbons
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The invention relates to a process for removing olefinic impurities from hydrogen-containing chlorofluorohydrocarbons (HCFCs) in which the contaminated HCFCs are passed in the gas phase at 200° to 400° C. over a zeolite.
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-
-
- The Fluorosulfines XF2C(F)C=SO (X = F, Cl, Br), Their Synthesis and Unusual Type of Decomposition
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A new route for the synthesis of the sulfenyl chloride 3 opens an easy access to fluoro(trifluoromethyl)sulfine (6) by hydrolysis of 3, trapping 6 by Diels-Alder reaction with anthracene, and thermolysis of the formed compound 8.By addition of the thioacetyl fluorides XF2C(F)C=S (X=Cl,Br) to anthracene compounds 9a,b are obtained, which could be oxidized to the sulfene adducts 12a,b as well as to the sulfine adducts 13a,b.Thermolysis of the latter yields the sulfines 17a,b, which are unstable at room temperature.A second approach to 17a involves oxidation of 1,3-dithietane 11a to its S-oxide 14a (e.g. via an S,S-difluoro compound 15a) and subsequent thermolysis, but thermal decomposition predominates.An unusual decomposition has been observed for 17a,b which was hitherto unknown for sulfines. Key Words: Fluorosulfines / Fluorothione S-oxides / Diels-Alder-Adducts
- Gradel, Jan,Sundermeyer, Wolfgang
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p. 1889 - 1894
(2007/10/02)
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- Hydrodechlorination of CCl2FCClF2 over NiO-Cr2O3 catalysts
-
The vapor-phase hydrodechlorination of CCl2FCClF2 CCl2FCClF2 + H2 -> ClFC=CF2 + HFC=CF2 + HCl is promoted at around 400 deg C by NiO-Cr2O3, especially by a mixture containing 70 atpercent of Cr.The catalytic activity of the mixed oxide is well maintained, and nearly 100percent conversion was observed even after a running time of 5.25 h.However, the reaction was not promoted by Cr2O3 alone, and CH4 formation and deactivation due to carbonaceous deposit on the surface were markedly promoted by NiO and NiO-Cr2O3 containing smaller amounts of Cr2O3.By reference to the results of XRDand XPS measurements, the excellent catalytic behavior of NiO-Cr2O3 (Cr content: 70 atpercent) was attributed to NiCr2O4 being dispersed by Cr2O3 on the surface.
- Okazaki, Susumu,Habutsu, Hisashi
-
p. 191 - 201
(2007/10/02)
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- IR Laser-induced Chemistry of some Perhaloethene-Silane Mixtures at Different Single Irradiating Wavelengths
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TEA CO2 laser-induced reactions in chlorotrifluoroethene-silane, 1,2-dichlorodifluoroethene-silane, 1,1-dichlorodifluoroethene-silane, and 1,2-dichlorodifluoroethene-trimethylsilane mixtures at medium (4-19 Torr) and in chlorotrifluoroethene-silane and 1,2-dichlorodifluoroethene-silane mixtures at low (1 Torr) pressures can be initiated by irradiation tuned to either perhaloethene or silane.The reaction progress at medium pressure and reaction products at low pressure depend on the particular wavelength employed.The former reactions are assumed to occur through reactive collision of both energized components in the mixture and have been shown to yield mostly tetrafluorosilane, trifluorosilane, hydrogen chloride, and other hydrocarbons.The latter are explained by multiphoton dissociation of the alkene into carbenes, subsequent reactions of these carbenes, and by 1,2-rearrangement of halogen in the transient CFCl=CF* radical produced upon C-Cl bond cleavage of the parent CFCl=CFCl compound.This reaction mechanism is in line with IR multiphoton decomposition of 1,2-dichlorodifluoroethene both in the absence and presence of chlorine and carbon monoxide.
- Pola, Josel,Simeonov, Sawa
-
p. 101 - 108
(2007/10/02)
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- Bi-Pd Catalyst for Selective Hydrodechlorination of 1,1,2-Trichlorotrifluoroethane to Trifluoroethene, a Key Intermediate to 1,1,1,2-Tetrafluoroethane as a CFC Replacement for Refrigeration
-
Trifluoroethene, a key intermediate to 1,1,1,2-tetrafluoroethane (FC-134a), was catalytically synthesized with 80-90percent selectivity at 80-100percent conversion in the hydrodechlorination of 1,1,2-trichlorotrifluoroethane (FC-113) at 200-250 deg C under an atmospheric pressure over Bi-Pd (Bi/Pd = 0.4-0.6) supported on metal oxides.
- Ohnishi, Ryuichiro,Suzuki, Isao,Ichikawa, Masaru
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p. 841 - 844
(2007/10/02)
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- Conversion of 1,1,2-Trichloro-1,2,2-trifluoroethane (CFC113) over TiO2-Supported Metal and Metal Oxide Catalysts
-
CCl2FCClF2 was converted to C2H2F2 and CH4 over Pd/TiO2 at 420-820 K in the presence of hydrogen.C2H2F2 and C2H3F3 were mainly formed over Pt/TiO2 at 520-570 K and dechlorination to CF3Cl took place over Ni/TiO2 and Co/TiO2 at 470-620 K.The CeO2/TiO2 catalyst and the catalyst containing La themselves reacted with CFC113 to give CeF3/TiO2 and LaF3/TiO2 after the reaction at 820 K, respectively.MnTiO3 catalyzed the reaction to C2F3Cl at relatively high temperatures of 770-820 K.
- Takita, Yusaku,Yamada, Hiroshi,Hashida, Masayo,Ishihara, Tatsumi
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p. 715 - 718
(2007/10/02)
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- Selective Hydrodechlorination of CFC-113 to 1-Chloro-1,2,2-trifluoroethylene over Supported Ni Catalysts
-
Various metal oxides have been examined as catalysts for the hydrodechlorination of CFC-113 to form 1-chloro-1,2,2-trifluoroethylene (CFC-1113).NiO was most effective and over silica gel- or Y-zeolite-supported Ni catalyst, 100 percent conversion of CFC-113 and 96percent selectivity to CFC-1113 were attained.
- Ueda, Wataru,Tomioka, Satoshi,Morikawa, Yutaka,Sudo, Motonori,Ikawa, Tsuneo
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p. 879 - 880
(2007/10/02)
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- All E-10,20-methanoretinoylopsin, light-stable rhodopsin. Synthesis and spectroscopy of all E-10,20-methano- and all-E-retinoyl fluoride and their reaction with bovine opsin
-
In order to obtain a light-stable rhodopsin as a potential candidate for crystallization and structural X-ray analysis, we synthesized and characterized the novel all E-10,20-methanoretinoyl fluoride (2).This retinal analogue has a locked 11-cis configuration, preventing the light-induced 11-cis -> trans isomerization and binds to opsin by a stable peptide bond rather than a Schiff base. 2 reacted with (methylated) bovine opsin, forming a light- and thermo-stable pigment with λmax at 390 nm.Its opsin shift (2500 cm-1) is in the same order of magnitude as that in rhodopsin (2650 cm-1), suggesting that the mechanism for the red shift is not located in the direct vicinity of the chromophore-protein linkage.We also report the first synthesis and characterization of all-E-retinoyl fluoride (10), which failed to give a pigment on reaction with bovine opsin.
- Steen, R. van der,Groesbeek, M.,Amsterdam, L. J. P. van,Lugtenburg, J.,Oostrum, J. van,Grip, W. J. de
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-
- SOLVENT EFFECTS IN BETWEEN PERFLUOROALKYLIODIDES AND CADMIUM
-
The interaction between perfluoroorgano iodides (RfI where Rf = F(CF3)2C(CF2CF2)3, n-C6F13, n-C8F17, F(CF3)2COCF2CF2, F(CF3)2CO(CF2CF2)4 and C2H5OC(O)(CF2CF2)2OCF2CF2) with cadmium in an acetonitrile solvent media produces primarily the coupled products (RfRf, 72-90percent yield) in addition to minor quantities of the reduction products (RfH).On the other hand ICF2CF2I and ClCF2CFClI, by a 1,2-dehalogenation reaction, from the olefins CF2=CF2 and CF2=CFCl, respectively, as the principal products.The interaction of RfI compounds with cadmium in other solvent media, e.g. diethyl ether, tetrahydrofuran (YHF)), N,N-dimethylformamide (DMF), and bis(2-methoxyethyl)ether(diglyme) were examined and found to produce a different ratio of RfRf and RfH products.
- Chen, Grace J.,Tamborski, Christ
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p. 123 - 140
(2007/10/02)
-
- IR Laser Chemistry and C-F Chromophore Absorption of 1,2-Dichloro-1,1,2-trifluoroethane
-
The photochemical-reaction yields after IR multiphoton excitation of CHFCl-CF2Cl are reported and evaluated in terms of the steady-state rate coefficient for reactant decay k(st) = 106.1+/-0.3(I/MWcm-2)s-1).The dominant primary reaction channels are α,β HCl and HF elimination, although minor pathways seem to include Cl2 elimination and other channels, which are discussed.The major uncertainty in the comparison with theoretical estimates resides in the fraction of C-F chromophore band strength with contributes to excitation.The total band strength for the range from 940 cm-1 to 1310 cm-1 is reported to be G = = 8.2 pm2.
- Lupo, Donald W.,Quack, Martin,Vogelsanger, Beat
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p. 129 - 138
(2007/10/02)
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- Reaction of 1,2-Dichloroiodotrifluoroethane With Zinc
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The zinc coupling reaction of 1,2-dichloroiodotrifluoroethane (I) in acetic anhydride-methylene chloride has been reinvestigated in more detail than its original disclosure.The expected coupling product C4F6Cl4 was shown to be an isomeric mixture of three components, CF2ClCFClCFClCF2Cl (II, 80percent), CFCl2CF2CF2CFCl2 (IIa, 15percent) and CF2ClCFClCF2CFCl2 (IIb, 5percent).In addition, other products e.g.CF2-CFCl, C6F9Cl5 and C8F12Cl6 were formed in minor quantities.A probable mode of formation of various byproducts via initial formation of CF2-CFCl and subsequent telomerization is presented.
- Eapen, K. C.,Tamborski, C.
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p. 421 - 424
(2007/10/02)
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- Pulse-Duration Effects on Competitive Reactions in Infrared Multiple-Photon Decomposition of CH2ClCHClF and CHClFCHClF
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Vibrationally excited 1,2-dichlorofluoroethane and 1,2-dichloro-1,2-difluoroethane have been observed to dissociate competitively via two channels to form vibrationally excited HCl and HF.The fluence dependences of the branching ratio have been measured for both "short"-pulse (80-ns fwhm) and "long"-pulse (80-ns fwhm with 1-μs-fwhm tail) irradiations.The branching ratio shows not only fluence dependence but also pulse-duration dependence, that is, intensity dependence.When the reactant pressure is 1.0 Torr, collisional deactivation is expected to occur to a considerable extent under long-pulse irradiation while it can be ignored under short-pulse irradiation.The experimental results are interpreted by using the exact stochastic method based on the energy-grained master equations, which take into account collisional deactivation.
- Ishikawa, Yo-ichi,Sugita, Kyoko,Arai, Shigeyoshi
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p. 5067 - 5071
(2007/10/02)
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- ELECTROSYNTHESIS OF CHLOROTRIFLUOROETHYLENE FROM 1,1,2-TRICHLOROTRIFLUOROETHANE ON WATER-REPELLENT ZINC DIFFUSION ELECTRODES.
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This paper reports on the applications of water-repellent zinc electrodes for the electrosynthesis of chlorotrifluoroethylene from 1,1,2-trichlorotrifluoroethane. The system studied is very promising with respect to current density, yield of the end product, and convenience of its utilization. However, it also has a serious drawback, the chemical instability of the wate-repellent zinc electrode, which leads to its dissolution during electrolysis, and conversion into a hydrophilic spongy zinc electrode. The current efficiency for CTFE on a hydrophilic spongy electrode with rear supply of Freon 113 is low, not exceeding 20%. Accordingly, an electrocatalyst chemically inert to 1,1,2-trichlorotrifluoroethane is needed for construction of a stable water-repellent electrode for the given process.
- Kornienko,Kalinichenko,Kedrinskii,Chirkov
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p. 1103 - 1106
(2007/10/02)
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- La modelisation des reacteurs electrochimiques. Exemples d'application
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The design of an electrochemical reactor should be approached by a modelling of its operation.With this in mind, we present here the general principles of such a modelling based on the methodology of electrochemical engineering.As an illustration, we give a short description of two examples; the electrolytic recovery of silver and a process for electroorganic synthesis.
- Savall, A.,Giron, M.,Lapicque, F.,Weise, L.,Storck, A.
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p. 1056 - 1060
(2007/10/02)
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- Photodissociation of 1,1,1-Trifluorodichloroethane at 147 nm. Evidence for Chlorine Atom Reactions
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The 147-nm photolysis of CF3CHCl2 has been investigated at 23 deg C as a function of reactant pressure and conversion (It/N), with and without nitric oxide as additive.The principal reaction product is CF2CHF, with lesser yields of CF2CFCl, CF2CHCl, and four chlorofluorobutanes.At constant CF3CHCl2 pressure the observed quantum yields of the olefins decrease with increasing It/N and there is a corresponding increase in the yields of the C4 products.The quantum yields of the olefins also decrease with increasing reactant pressure at the same values of It/N.The addition of NO completely suppresses the formation of the chlorofluorobutanes, but there is a marked increase in the olefin quantum yields.These observations are interpreted in terms of reactions of chlorine atoms which derive, primarily, from the α,α elimination of the elements of (Cl)2 in the primary process.Clorine atoms so produced abstract hydrogen from the parent and add to the product olefins, processes which are the source of haloethyl radicals in the system.Nitric oxide provides an additional and dominant channel for chlorine atom removal by way of their NO-catalyzed recombination which proceeds through CINO as an intermediate.A reaction mechanism consistent with the observations is proposed and, from the functional dependence of the olefin quantum yields on It/N, limiting values have been obtained by extrapolation.The rate constant ratio for hydrogen abstraction from CF3CHCl2 by Cl atoms to Cl addition to CF2CHF was found to be k5/k6 = (2.2 +/- 0.5)*E-4.The extinction coefficient for CF3CHCl2 at 147 nm (296 K) has been determined as ε = (1/PL) ln(I0/It) = 590 +/- 60 atm-1Cm-1.
- Yano, T.,Jung, K.-H.,Tschuikow-Roux, E.
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p. 2146 - 2151
(2007/10/02)
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