- Infrared multiphoton dissociation of CBrF2CHClF, CBrF2CHBrF, and CBrClFCBrF2 in a molecular beam
-
Dynamics and mechanisms of infrared multiphoton dissociation of CBrF2CHClF, CBrF2CHBrF, and CBrClFCBrF2 have been studied using a photofragmentation translational spectroscopy.All molecules dissoociated through C-Br bond rupture reactions.At high laser fluence, the halogenated ethyl radicals produced by the primary dissociation reactions dissociated through carbon-halogen bond ruptures.Center-of-mass product translational energy distributions for the C-Br and C-Cl bond ruptures of all halogenated ethanes and ethyl radicals studied are essentially consistent with those calculated by Rice-Ramsperger-Kassel-Marcus (RRKM) theory.This indicates that there exists essentially no exit channel barrier on the potential energy surface for the C-Br or C-Cl bond rupture of the halogenated ethanes and ethyl radicals.
- Yokoyama, Atsushi,Yokoyama, Keiichi,Fujisawa, Ginji
-
-
Read Online
- High-vacuum pyrolysis of 1,1,1-trifluoro-2-bromo-2-chloroethane. IR spectrum of 1,1,1-trifluoro-2-chloroethyl radical in an argon matrix
-
The products of high-vacuum pyrolysis of 1,1,1-trifluoro-2-bromo-2-chloroethane were studied by matrix IR spectroscopy. The decomposition of 1,1,1-trifluoro-2-bromo-2-chloroethane was shown to occur predominantly via two directions: to form the 1,1,1-trifluoro-2-chloroethyl radical and trifluoromethylcarbene isomerizing to trifluoroethylene. The CF3CHCl radical has been detected in the matrix for the first time. The bands observed in the IR spectrum were calculated by the quantum-chemical B3LYP/6-311G(d,p) method and assigned to normal vibrations of the radical.
- Baskir,Korolev,Nefedov
-
-
Read Online
- Telomerization of perfluoropoly(oxamethylene iodides) with trifluoroethylene
-
Radical telomerization of perfluoropoly(oxamethylene iodides) with trifluoroethylene was studied. Based on the 1H and 19F NMR spectroscopic data, the pathways for olefin addition to the iodide in the initial and subsequent stages were examined.
- Emel'yanov,Rodin,Blinov,Berenblit
-
-
Read Online
- Effect of calcination temperature and fluorination treatment on NiF2-AlF3 catalysts for dehydrofluorination of 1, 1, 1, 2-tetrafluoroethane to synthesize trifluoroethylene
-
High-performance NiF2-AlF3 fluoride catalysts for the catalytic dehydrofluorination of 1, 1, 1, 2-tetrafluoroethane (CF3CH2F) were prepared by impregnation and fluorination methods. The effect of calcination temperature and vapor-phase fluorination on the properties of NiF2-AlF3 catalysts were investigated by BET, SEM, XRD, UV-DRS, Raman, IR, TG and XPS. By increasing the calcination temperature, the NiO species diffused from the surface into the inside bulk phase of the alumina support and the inverse spinel NiAl2O4 was formed at a calcination temperature up to 600 °C. Vapor-phase fluorination can improve the stability of the catalytic dehydrofluorination. The unfluorinated NiAl2O4 affected the surface area and acidity of NiF2-AlF3 catalyst. The acid sites of catalysts were investigated by py-IR, disclosing that the affinity of Lewis acid sites toward activity of catalysts. In addition, it was found that the weak and medium Lewis acid sites derived from NiF2-AlF3 complex phase are active centers for catalyzing dehydrofluorination of CF3CH2F to trifluoroethylene (CF2=CHF). The highest activity was obtained over a fluorinated catalyst calcined at 500 °C, with a reaction rate of 2.13 mmol min?1 gcat.?1 and a trifluoroethylene selectivity of 99%, highlighting a good prospect for the commercial application.
- Jia, Wenzhi,Chen, Yanfeng,Liu, Min,Liu, Xing,Liu, Xinhua,Yuan, Juanjuan,Lu, Xiaoju,Zhu, Zhirong
-
-
Read Online
- Selective liquid-phase hydrodechlorination of chlorotrifluoroethylene over palladium-supported catalysts: Activity and deactivation
-
Liquid-phase hydrodechlorination of chlorotrifluoroethylene (CTFE) to trifluoroethylene (TrFE) with molecular hydrogen was studied over palladium-supported catalysts. BaSO4, Al2O3 and activated carbon (AC) were used as supports, respectively. The results showed that the Pd/AC catalysts exhibit higher activity than Pd/BaSO4 and Pd/Al2O3. The treatment of activated carbon with HNO 3 led to a considerable increase of surface functional groups containing oxygen atoms, which resulted in a higher dispersion of palladium on the supports and enhancement of catalytic activity. The stability of the catalyst was investigated, one reason for the inhibition was the accumulation of NaCl on the surface of Pd/AC that blocks the pores of carbon support. The activity of Pd/AC could partially recovered by washing with water. The other irreversible deactivation of the catalyst are from the change of particle size and the pore structure, leaching of Pd, a decrease of BET surface area and Pd surface area of Pd/AC catalyst.
- Meng, Bao-Chuan,Sun, Zhao-Yang,Ma, Jin-Peng,Cao, Gui-Ping,Yuan, Wei-Kang
-
-
Read Online
- 19F and 27Al MAS NMR Study of the Dehydrofluorination Reaction of Hydrofluorocarbon-134 over Basic Faujasite Zeolites
-
Dehydrofluorination of hydrofluorocarbon-134 (CF2HCF2H) occurs over the basic zeolite NaX at 275 deg C, to produce HFC-1123 (CF2CFH) and tetrahedrally-coordinated aluminum fluoride species.Under moist conditions, the tetrahedral aluminum fluoride species are hydrolyzed and six-coordinate species are formed.The framework of the less basic zeolite NaY is not attacked by HFC-134 under similar conditions.
- Grey, Clare P.,Corbin, David R.
-
-
Read Online
- Catalytic dehydrofluorination of 1,1,1,2-tetrafluoroethane to synthesize trifluoroethylene over a modified NiO/Al2O3 catalyst
-
A promising fluorinated NiO/Al2O3 catalyst for synthesizing trifluoroethylene through the catalytic dehydrofluorination of CF3CFH2 was prepared, and the relationship between the Lewis acid sites and activity was investigated. 20.1% conversion of CF3CFH2 was observed, and the selectivity to trifluoroethylene was observed to be 99% at 430°C after 100 h.
- Jia, Wenzhi,Liu, Min,Lang, Xuewei,Hu, Chao,Li, Junhui,Zhu, Zhirong
-
-
Read Online
- Influence of Lewis Acidity on Catalytic Activity of the Porous Alumina for Dehydrofluorination of 1,1,1,2-Tetrafluoroethane to Trifluoroethylene
-
The porous alumina catalysts with different acidity were prepared and tested for dehydrofluorination of 1,1,1,2-tetrafluoroethane to synthesize trifluoroethylene. The XRD, BET, SEM, NH3-TPD and py-IR techniques were used to characterize the alumina catalysts with different calcination temperatures. The porous θ-Al2O3 showed the excellent catalytic performance, with 35.1 % conversion and the selectivity to trifluoroethylene of 99.0 %. The active sites of catalysts for formation of trifluoroethylene are appropriate weak Lewis acid sites, and the strong Lewis acid sites may result in its rapid deactivation, due to the coke or polymerization of trifluoroethylene. Graphical Abstract: Dehydrofluorination of 1,1,1,2-tetrafluoroethane (CF3CFH2) is a promising route to synthesize trifluoroethylene over θ-Al2O3, the conversion is 35.1 % and the selectivity to trifluoroethylene is 99 % at 450°C. It was suggested that appropriate number of weak Lewis acid sites was beneficial to the catalysis for dehydrofluorination of CF3CFH2, the weak Lewis acid sites as the active sites of synthesis of trifluoroethylene. On the other hand, the strong Lewis acid sites easily result in deactivation of catalysts derived from the coke or polymerization of trifluoroethylene.[Figure not available: see fulltext.]
- Jia, Wenzhi,Wu, Qian,Lang, Xuewei,Hu, Chao,Zhao, Guoqing,Li, Junhui,Zhu, Zhirong
-
-
Read Online
- Synthetic method of ethyl 4, 4-difluoro-3-oxo-2-piperidine-1-yl methylene butyrate
-
The invention relates to a synthetic method of ethyl 4, 4-difluoro-3-oxo-2-piperidine-1-methylene butyrate. The synthetic method comprises the following steps: 1, carrying out a condensation reactionon difluoroacetyl fluoride and 3-(1-piperidyl)-ethyl acrylate to generate 4, 4-difluoro-3-oxo-2-piperidine-1-yl methylene ethyl butyrate and hydrogen fluoride, and 2, carrying out a reaction on the hydrogen fluoride generated in the step 1 and trichloroethylene under the action of a fluorination catalyst to generate trifluoroethylene and hydrogen chloride, and 3, reacting the trifluoroethylene generated in the step 2 with oxygen under the action of a complex catalyst to generate difluoroacetyl fluoride, and recycling the difluoroacetyl fluoride generated in the step 3 as a reactant in the step1. According to the synthetic method of the ethyl 4, 4-difluoro-3oxo-2-piperidine-1-methylene butyrate, the raw materials are simple and easy to obtain, the atom utilization rate is high, and the production safety is high.
- -
-
Paragraph 0028; 0038; 0046; 0054; 0062; 0070
(2021/01/30)
-
- 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.
- -
-
Page/Page column 12; 17
(2020/07/15)
-
- Selective Copper Complex-Catalyzed Hydrodefluorination of Fluoroalkenes and Allyl Fluorides: A Tale of Two Mechanisms
-
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.
- Andrella, Nicholas O.,Xu, Nancy,Gabidullin, Bulat M.,Ehm, Christian,Baker, R. Tom
-
supporting information
p. 11506 - 11521
(2019/08/20)
-
- MANUFACTURING METHOD OF HYDROFLUOROOLEFIN
-
A method for manufacturing hydrofluoroolefin, includes: converting hydrofluorocarbon represented by a formula (1) into hydrofluoroolefin (HFO) represented by formula (2) in the presence of carbon dioxide to obtain a first gas composition containing hydrofluoroolefin and carbon dioxide; and separating carbon dioxide contained in the first gas composition to obtain a second gas composition containing HFO, CR1R2X1CR3R4X2 . . . (1), CR1R2═CR3R4 . . . (2), wherein R1 to R3 are each independently hydrogen atom or fluorine atom, R4 is hydrogen atom, fluorine atom, CH3, CH2F, CHF2 or CF3, the total number of fluorine atoms of R1 to R4 is one or more, and the total number of hydrogen atoms of R1 to R4 is one or more, X1 and X2 are each hydrogen atom or fluorine atom where X2 is the fluorine atom when X1 is the hydrogen atom, and X2 is the hydrogen atom when X1 is the fluorine atom.
- -
-
Paragraph 0144-0157; 0165
(2018/03/01)
-
- Organocatalytic C?F Bond Activation with Alanes
-
Hydrodefluorination reactions (HDF) of per- and polyfluorinated olefins and arenes by cheap aluminum alkyl hydrides in non-coordinating solvents can be catalyzed by O and N donors. TONs with respect to the organocatalysts of up to 87 have been observed. Depending on substrate and concentration, high selectivities can be achieved. For the prototypical hexafluoropropene, however, low selectivities are observed (E/Z≈2). DFT studies show that the preferred HDF mechanism for this substrate in the presence of donor solvents proceeds from the dimer Me4Al2(μ-H)2?THF by nucleophilic vinylic substitution (SNV)-like transition states with low selectivity and without formation of an intermediate, not via hydrometallation or σ-bond metathesis. In the absence of donor solvents, hydrometallation is preferred but this is associated with inaccessibly high activation barriers at low temperatures. Donor solvents activate the aluminum hydride bond, lower the barrier for HDF significantly, and switch the product preference from Z to E. The exact nature of the donor has only a minimal influence on the selectivity at low concentrations, as the donor is located far away from the active center in the transition states. The mechanism changes at higher donor concentrations and proceeds from Me2AlH?THF via SNV and formation of a stable intermediate, from which elimination is unselective, which results in a loss of selectivity.
- Jaeger, Alma D.,Ehm, Christian,Lentz, Dieter
-
supporting information
p. 6769 - 6777
(2018/04/02)
-
- METHOD FOR PRODUCING TRIFLUOROETHYLENE
-
To provide a production process with high degree of conversion of HFC-134a and selectivity for HFO-1123, with a high productivity of HFO-1123 and with a small load in process of purification and recovery. A process for producing HFO-1123, which comprises bringing a material gas having a proportion of HFC-134a based on the total amount of a diluent gas and HFC-134a of from 50 to 100 mol % into contact with a dehydrofluorination catalyst to convert part of HFC-134a into HFO-1123, then removing hydrogen fluoride in a reaction product gas, and then bringing the reaction product gas from which hydrogen fluoride has been removed into contact with a dehydrofluorination catalyst to convert at least part of unreacted HFC-134a into HFO-1123.
- -
-
Paragraph 0114; 0115
(2017/01/31)
-
- Method for preparing hexafluoro-1,3-butadiene
-
The invention relates to a method for preparing hexafluoro-1,3-butadiene. The method comprises the following steps: performing reduction dechloridation on 1,2-dichloro-1,1,-2-halothane with zinc powder to obtain a CF2=CHF gas phase intermediate product, introducing into liquid bromine to carry out an addition reaction, and obtaining CBrF2CHBrF; evaporating CBrF2CHBrF in an evaporator to generate a gas, and using a reaction tube filled with a first catalyst to remove one molecule HBr and generate trifluorovinyl bromide; performing two steps of reactions on the trifluorovinyl bromide under the action of the zinc powder, the solvent and a second catalyst, thereby obtaining the hexafluoro-1,3-butadiene. The method has the advantages of being simple in process, high in yield, easy in raw material obtaining, easy in industrialization, green and environment-friendly.
- -
-
Paragraph 0057; 0058; 0059; 0060
(2017/08/27)
-
- A synthetic hexafluoro - 1, 3 - butadiene method (by machine translation)
-
The invention relates to a method for synthesizing hexafluoro-1,3-butadiene, and belongs to the field of organic chemistry synthesis. The method for synthesizing hexafluoro-1,3-butadiene comprises the following steps: removing hydrogen fluoride from tetrafluoro ethane (HFC-134a) under the action of a catalyst to generate trifluoroethylene; rapidly reacting trifluoroethylene with liquid bromine to generate 1,2-dibromo-1,1,2-trifluoroethane, and removing hydrogen bromide under alkaline conditions to obtain trifluorobromoethylene; and reacting trifluorobromoethylene with activated zinc powder and N,N-dimethyl formamide to generate trifluorovinylzinc, and carrying out a coupling reaction on trifluorovinylzinc under the action of Fe to generate hexafluoro-1,3-butadiene. A solvent can be recovered after above reactions. The method has the advantages of low price and convenient source of raw materials, good stability and long service of the catalyst, simple separation and purification of the above product, and easy industrial production.
- -
-
Paragraph 0038; 0043
(2017/09/26)
-
- Method for preparing fluorinated compound CH2F-R (R is H or CF3) through difluoromethane pyrolysis
-
The invention discloses a method for preparing a fluorinated compound CH2F-R (R is H or CF3) through difluoromethane pyrolysis. According the method, the fluorinated compound is obtained through a gas-phase reaction between difluoromethane and CH4, NH3, H2O or H under the circumstance that no catalyst exists. The following reaction conditions of the method are achieved: the reaction pressure is 0.1-1.5 MPa; the reaction temperature is 700-1000 DEG C; the mole ratio of difluoromethane to any one or more of CH4, NH3, H2O and H is 1:(0-40); and the residence time is 0.1-50 s. The method disclosed by the invention has the advantages that the raw material, namely difluoromethane, is easy to obtain; no catalyst needs to use; the operation and the control are easy; and the experimental repeatability is high.
- -
-
Paragraph 0038-0041
(2017/05/18)
-
- METHOD FOR PRODUCING FLUORINE-CONTAINING OLEFIN
-
A method for producing at least one compound selected from the group consisting of a compound represented by the following formula (10), a compound represented by the following formula (11), a compound represented by the following formula (12), and a compound represented by the following formula (13), which the method containing reacting a compound represented by the following formula (2) with a compound represented by the following formula (7), in the presence of at least one compound selected from the group consisting of a compound represented by the following formula (1), a compound represented by the following formula (3), a compound represented by the following formula (4), a compound represented by the following formula (8), and a compound represented by the following formula (9).
- -
-
Paragraph 0284-0294
(2016/07/27)
-
- A process for the preparation of trifluoro-ethylene
-
The invention discloses a method for preparing trifluoroethylene by a vapor phase method. The method comprises that 1,1,1,2-tetrafluoroethane as a raw material undergoes a one-step vapor phase reaction in the presence of a fluorination cracking catalyst at a temperature of 380-500 DEG C so that trifluoroethylene is obtained after hydrogen fluoride removal. A preparation method of the fluorination cracking catalyst comprises the following steps of preparing an Al-Fe-Mg compound from Al, Fe and Mg soluble salts by a certain method, carrying out equivalent-volume impregnation on the compound with a La or Ce assistant, carrying out drying and roasting to obtain a catalyst precursor and carrying out HF fluorination. The preparation method realizes a 1,1,1,2-tetrafluoroethane conversion rate greater than 50% and even reaching to 65.1% and the highest product trifluoroethylene selectivity of 99.3%.
- -
-
Paragraph 0039; 0040
(2016/12/22)
-
- METHOD FOR PRODUCING TRIFLUOROETHYLENE
-
To produce trifluoroethylene stably with a high selectivity by reacting 1,1,1,2-tetrafluoroethane with a solid reactant efficiently while formation of by-products such as polymer carbon is suppressed. A material gas containing 1,1,1,2-tetrafluoroethane is made to flow through a layer consisting of a particulate solid reactant having an average particle size of from 1 μm to 5,000 μm to bring the solid reactant and 1,1,1,2-tetrafluoroethane into contact with each other in a state where the layer consisting of the solid reactant is fluidized.
- -
-
Paragraph 0087-0092
(2016/12/01)
-
- METHOD FOR PRODUCING TRIFLUOROETHYLENE
-
To efficiently produce trifluoroethylene stably by using 1,1,1,2-tetrafluoroethane, without clogging of a reactor, addition of extra process, a decrease in the yield of a product, and the like. A material gas containing 1,1,1,2-tetrafluoroethane and calcium oxide are brought into contact with each other in a reactor. The material gas in a gaseous phase and calcium oxide in a solid phase are brought into contact with each other.
- -
-
Paragraph 0106-0108; 0116
(2016/12/01)
-
- METHOD FOR PURIFYING FLUID THAT INCLUDES TRIFLUOROETHYLENE, AND METHOD FOR PRODUCING TRIFLUOROETHYLENE
-
To provide a method for purifying trifluoroethylene, by which from a fluid containing trifluoroethylene, a C1-5 alkane or alkene (excluding trifluoroethylene) in which at least one hydrogen atom may be substituted with a chlorine atom or a fluorine atom can be efficiently removed, and a method for producing trifluoroethylene by which trifluoroethylene can be efficiently produced. A fluid containing trifluoroethylene is brought into contact with at least one type of synthetic zeolite selected from synthetic zeolites 3A, 4A and 5A.
- -
-
Paragraph 0095-0107
(2016/12/22)
-
- METHOD OF PURIFYING TRIFLUOROETHYLENE
-
PROBLEM TO BE SOLVED: To provide a method of removing hydrochloric acid, from a product comprising trifluoroethylene and hydrochloric acid, without generating hazardous substance, and thus purifying trifluoroethylene. SOLUTION: A method of purifying trifluoroethylene has a step of bringing a gas composition comprising trifluoroethylene and hydrochloric acid into contact with an acid component removal liquid with an alkali concentration of 40 mass% or less to remove the hydrochloric acid. The acid component removal liquid may be water. SELECTED DRAWING: Figure 1 COPYRIGHT: (C)2016,JPOandINPIT
- -
-
Paragraph 0049-0054
(2017/02/24)
-
- METHOD FOR PRODUCING TRIFLUOROETHYLENE
-
PROBLEM TO BE SOLVED: To provide a method for producing 1-chloro-1,2-difluoroethylene efficiently and economically in an industrially practicable method. SOLUTION: A method for producing trifluoroethylene includes bringing 1-chloro-1,2,2-trifluoroethane and/or 1-chloro-1,1,2-trifluoroethane into contact with alkali aqueous solution in the presence of a phase transfer catalyst for a dehydrochlorination reaction. SELECTED DRAWING: None COPYRIGHT: (C)2016,JPO&INPIT
- -
-
Paragraph 0068; 0071
(2018/10/16)
-
- Theoretical and experimental studies for preparing 1, 1-dibromo-1,2,2,2-tetrafluoroethane on gas-phase bromination of 1,1,1,2-tetrafluoroethane
-
Efficient gas-phase bromination of 1, 1, 1, 2-tetrafluoroethane (HFC-134a) for the preparation of 1, 1-dibromo-1, 2, 2, 2-tetrafluoroethane (CF3CFBr2) has been described for the first time. A wide-ranging experimental investigation o
- Hu, Ruzhu,Zhang, Chengping,Qing, Feiyao,Quan, Hengdao
-
-
- METHOD FOR SYNTHESISING TRIFLUOROETHYLENE FROM CHLOROTRIFLUOROETHYLENE
-
The present invention relates to the preparation of trifluoroethylene (VF3 or TrFE) by hydrogenolysis of chlorotrifluoroethylene (CTFE) in the gaseous phase over a group VIII metal catalyst deposited on a support. This method can be used to obtain VF3 in an economical manner in conditions which minimize the risk of explosion of this molecule. Using a catalyst containing a group VIII metal and, more specifically, containing Pd deposited on a support and a specific series of steps of separation and purification makes it possible to obtain excellent CTFE conversion rates and high selectivity in VF3 at atmospheric pressure and at low temperatures.
- -
-
Paragraph 0060-0081
(2015/04/15)
-
- METHOD FOR PRODUCING TRIFLUOROETHYLENE
-
PROBLEM TO BE SOLVED: To provide an economically advantageous method for efficiently producing high purity trifluoroethylene by using easily available raw materials without using a catalyst by a synthetic reaction accompanied by thermal decomposition. SOLUTION: There is provided a method for producing trifluoroethylene from tetrafluoroethylene and hydrogen by a synthetic reaction accompanied by thermal decomposition, the method comprising: (a) a step of mixing tetrafluoroethylene and hydrogen in advance to feed into a reactor or feeding tetrafluoroethylene and hydrogen separately into a rector; (b) a step of feeding a heating medium into the reactor; and (c) a step of bringing the tetrafluoroethylene and the hydrogen into contact with each other in the reactor in a state of controlling the temperature inside the reactor at 400 to 950°C to generate the trifluoroethylene. COPYRIGHT: (C)2015,JPOandINPIT
- -
-
Paragraph 0017; 0047-0052
(2018/12/12)
-
- METHOD OF PRODUCING TRIFLUOROETHYLENE
-
PROBLEM TO BE SOLVED: To provide an economically advantageous method for producing industrially useful trifluoroethylene with high productivity by using easily available HCFC-124 as raw material while not using any catalyst. SOLUTION: A method of producing trifluoroethylene includes the step of bringing a reductive compound and 1,1,1,2-tetrafluoro-2-chloroethane into contact with each other, without using any catalyst, at a temperature of 400-1200°C. COPYRIGHT: (C)2016,JPO&INPIT
- -
-
Paragraph 0056-0058
(2017/01/02)
-
- METHOD OF PRODUCING 2,3,3,3-TETRAFLUOROPROPENE AND 1,1-DIFLUOROETHYLENE
-
PROBLEM TO BE SOLVED: To provide an economically advantageous method that produces industrially useful HFO-1234yf and VdF by a single reaction associated with heat decomposition by use of easily available raw material. SOLUTION: This invention provides a method of producing 2,3,3,3-tetrafluoropropene and 1,1-difluoroethylene by a synthetic reaction associated with heat decomposition from a raw material composition comprising octafluorocyclobutane and methane. COPYRIGHT: (C)2015,JPOandINPIT
- -
-
Paragraph 0050-0054; 0059
(2016/12/22)
-
- Base-free Hiyama coupling reaction via a group 10 metal fluoride intermediate generated by C-F bond activation
-
A Pd(0)-catalyzed Hiyama coupling reaction of tetrafluoroethylene (TFE) proceeded without the use of a base to give α,β,β- trifluorostyrene derivatives. A Ni(0)-catalyzed Hiyama coupling reaction of perfluoroarenes also occurred without a base. The key intermediate in these reactions would be a transition-metal fluoride complex that is generated in situ by the oxidative addition of a C-F bond.
- Saijo, Hiroki,Sakaguchi, Hironobu,Ohashi, Masato,Ogoshi, Sensuke
-
supporting information
p. 3669 - 3672
(2014/08/18)
-
- Preparation of trifluorovinyl compounds by lithium salt-promoted monoalkylation of tetrafluoroethene
-
Treatment of tetrafluoroethene (TFE) with diethylzinc in the presence of lithium iodide gave 1,1,2-trifluoro-1-butene in moderate yield. In the absence of lithium iodide, however, the nucleophilic addition of diethylzinc to TFE proceeded very slowly to afford ethyl 1,1,2,2-tetrafluorobutylzinc. The addition of lithium iodide to a solution of ethyl-1,1,2,2-tetrafluorobutylzinc resulted in a smooth transformation into 1,1,2-trifluoro-1-butene. In the presence of lithium chloride, the reaction of TFE with benzyl or allyl Grignard reagents afforded the corresponding monosubstituted products in good to excellent yields.
- Ohashi, Masato,Kamura, Ryohei,Doi, Ryohei,Ogoshi, Sensuke
-
supporting information
p. 933 - 935
(2013/09/02)
-
- PROCESS FOR THE SYNTHESIS OF TRIFLUOROETHYLENE
-
A catalytic process for the synthesis of trifluoroethylene from chlorotrifluoroethylene which comprises contacting chlorotrifluoroethylene with hydrogen in the presence of a catalyst consisting of palladium or platinum supported on extruded activated carbon.
- -
-
Page/Page column 6-7
(2012/01/14)
-
- Experimental and chemical kinetic study of the pyrolysis of trifluoroethane and the reaction of trifluoromethane with methane
-
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.
- 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)
-
- PREPARATION OF HALOGEN AND HYDROGEN CONTAINING ALKENES OVER METAL FLUORIDE CATALYSTS
-
Halogenated alkenes, especially fluorinated alkenes can be prepared from halogenated and fluorinated alkanes, respectively, by dehydrohalogenation or dehydrofluorination in the presence of a high-surface metal fluoride or oxifluoride. Preferably, trifluoroethylene, pentafluoropropene, tetrafluorobutenes or trifluorobutadiene are prepared. Aluminium fluoride is highly suitable. The metal fluoride or oxifluoride can be applied supported on a carrier.
- -
-
Page/Page column 18-19
(2009/03/07)
-
- Conversion of CHF3 to CH2=CF2 via reaction with CH4 and CaBr2
-
Reaction of CHF3 and CH4 over CaBr2 was investigated at 400-900°C as a potential route for transforming the highly potent greenhouse gas, CHF3, into the valuable product CH 2=CF2. The homogeneous reaction of CHF3 with CH4 was also studied to assist in understanding the chemistries involved. Compared to the gas phase reaction, the addition of CaBr2 as a reactant increases the conversion of CHF3 and CH4 significantly at low temperatures while to a lesser extent at higher temperatures. In the absence of CaBr2, besides the target product, CH2=CF2, a large amount of C2F4 forms. On addition of CaBr2, the rate of formation of C 2F4 drops dramatically to near zero, while the rate of formation of CH2=CF2 increases considerably at temperatures below 880°C. Experimental and theoretical studies suggest that CHF3 strongly interacts with CaBr2, resulting in the fluorination of CaBr2 to CaF2, the release of active Br species results in the selective formation of CBrF3. The subsequent reactions involving Br, methane, and CBrF3 play a major role in the observed enhanced yield of CH2=CF2.
- Han, Wenfeng,Yu, Hai,Kennedy, Eric M.,Mackie, John C.,Dlugogorski, Bogdan Z.
-
p. 5795 - 5799
(2008/12/22)
-
- CHEMICAL PRODUCTION PROCESSES AND SYSTEMS
-
Chemical production processes are provided that include reacting a metal comprising olefin to form a conjugated olefin; reacting a heterohalogenated olefin to form a conjugated olefin; reacting a halogenated alkane to form a conjugated olefin; and/or reacting a hydrohalogenated olefin to form a conjugated olefin. Chemical production systems are also provided that can include: a first reactant reservoir configured to house a perhalogenated olefin; a second reactant reservoir configured to house a catalyst mixture; a first reactor coupled to both the first and second reservoirs, the first reactor configured to house a metal-comprising mixture and receive both the perhaloganated olefin form the first reactant reservoir and the reactant mixture from the second reactant reservoir; and a product collection reservoir coupled to the first reactor and configured to house a conjugated olefin.
- -
-
Page/Page column 16
(2008/06/13)
-
- Noncatalytic manufacture of 1,1,3,3,3-pentafluoropropene from 1,1,1,3,3,3-hexafluoropropane
-
1,1,3,3,3-Pentafluoropropene (CF3CH═CF2, HFC-1225zc) can be produced by pyrolyzing 1,1,1,3,3,3-hexafluoropropane (CF3CH2CF3, HFC-236fa) in the absence of dehydrofluorination catalyst at temperatures of from about 700° C. to about 1000° C. and total pressures of about atmosphere pressure in an empty, tubular reactor, the interior surfaces of which comprise materials of construction resistant to hydrogen fluoride.
- -
-
Page/Page column 3-4
(2008/06/13)
-
- NOVEL CATALYTIC METHOD FOR THE PRODUCTION OF FLUOROALKYLENES FROM CHLOROFLUOROHYDROCARBONS
-
A process for producing a producing a product of the formula: [in-line-formulae]R—CF═CHR1 [/in-line-formulae] wherein R is F or CF3 and R1 is F when R is F and is H when R is CF3 by reacting a reactant of the formula: [in-line-formulae]CF3—R2 [/in-line-formulae] wherein R2 is selected from wherein R3 is H, F or Cl and R4 is H or Cl, in the presence of a suitable catalyst, with a reducing agent selected from methane, methyl chloride and mixtures thereof, in a gas phase reaction.
- -
-
Page/Page column 4
(2008/06/13)
-
- PREPARATION OF HALO-OLEFIN
-
A process for preparing a halo-olefin to minimize one or more side reactions which form at least one impurity, said process comprising contacting a halogenated hydrocarbon with a metal dehalogenating agent dissolved in a solvent under conditions sufficient to dehalogenate said halogenated hydrocarbon to produce a product stream comprising said halo-olefin and at least one impurity, said metal dehalogenating agent having an average particle size within a range of average particle sizes, said impurity concentration of said product stream being essentially constant within said range and increasing significantly below said range.
- -
-
Page/Page column 13-14; 14-15; 15-16; 16
(2008/06/13)
-
- PROCESS FOR PRODUCTION OF 1,1,1,2-TETRAFLUOROETHANE AND/OR PENTAFLUOROETHANE AND APPLICATIONS OF THE SAME
-
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.
- -
-
Page/Page column 11; 16
(2008/06/13)
-
- Nucleophilic vinylic substitution with transition metal carbonyl anions - A rare case of a halophilic reaction mechanism. Formation of halo(acyl)rhenate complexes and X-ray structure of cis-[CF2=CF(CO)Re(CO)4Br]Na
-
Reactions of polyfluorinated alkenyl halides Z-(CF3) 3CCF=6;CFHal (Hal=Cl,I-Cl, Hal=Br, I-Br) and CF2=CFBr (II-Br) with [CpFe(CO)2]K (FpK) and [Re(CO)5]Na proceed through the initial attack of metal carbonyl anion on halogen. Reaction with FpK gives minor amounts of σ-alkenyl complexes Z-RfCF=CFFe(CO)2Cp (I-Fe, II-Fe) (3-30%), but primarily leads to dimer [CpFe(CO)2] 2. Reaction with [Re(CO)5]Na produces anionic halo(acyl)rhenates cis-[Z-RfCF=CF(CO)Re(CO)4Hal]Na (V-Cl, V-Br, VI) (70-90%) which were isolated, and halo(acyl)rhenate VI (Rf=F) was characterized by X-ray structure analysis. Halo(acyl)rhenates result from the attack of the intermediate carbanion [RfCF=CF]- on the carbonyl ligand of Re(CO) 5Hal. The involvement of [RfCF=CF]- is demonstrated by their trapping with t-BuOH or CH-acid, which gives the protodehalogenated alkenes I-H and II-H, and suppresses the nucleophilic substitution reaction leading to I-Fe, II-Fe or V-Cl. Arguments against a radical/SET mechanism for the substitution reaction are also advanced.
- Sazonov,Artamkina,Khrustalev,Antipin,Beletskaya
-
-
- Thermal isomerization of 1,1,2,2-tetrafluoroethane (FC-134) to 1,1,1,2-tetrafluoroethane (FC-134a) in the presence of hydrogen
-
The mechanism of the high-temperature, gas-phase isomerization of 1,1,2,2-tetrafluoroethane (FC-134) to 1,1,1,2-tetrafluoroethane (FC-134a) in the presence of H2 has been explored both experimentally and computationally. Studies of the impact of temperature, H2/FC-134 ratio, and contact time on conversion and yield, as well as a study of deuterium incorporation when D2 was used in place of H2, led to the conclusion that a free radical chain mechanism involving rearrangement of CHF2CF2· to CF3CHF· is involved.
- Romelaer,Baker,Dolbier Jr.
-
p. 6773 - 6777
(2007/10/03)
-
- (Fluoroorgano)fluoroboranes and -fluoroborates: Part 3. Polyfluoroalken-1-yldifluoroboranes
-
Polyfluoroalken-1-yldifluoroboranes RCF=CFBF2 (R=F, cis-, trans-Cl, trans-C4F9, cis-C2F5, cis-C6F13, trans-C4H9, trans-C6H5) were prep
- Frohn,Bardin
-
-
- Gas-phase kinetics of the self reactions of the radicals CH2F and CHF2
-
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
- Beiderhase, Thomas,Hack, Walter,Hoyermann, Karlheinz,Olzmann, Matthias
-
p. 625 - 641
(2007/10/03)
-
- Shock-Tube Study of the Pyrolysis of the Halon Replacement Molecule CF3CHFCF3
-
The kinetics of pyrolysis of CF3CHFCF3 have been studied in dilute mixtures (0.5 and 3 mol percent) in argon in a single-pulse shock tube over the temperature range of 1200-1500 K, residence times behind the reflected shock of between 650 and 850 μs, and pressures between 16 and 18 atm. Fluorinated products were quantified with gas chromatography and Fourier transform infrared spectroscopy; identification of unknown fluorocarbons and hydrofluorocarbons was performed with gas chromatography-mass spectrometry. The most significant products detected were C2F6, CF2=CHF, C2F4, C3F6, cyclo-C3F6, and CF3CHFCF2H. Traces of CF3H, CF4, C2F5H, C3F8, C4F6, and isomers of C4F8 were also identified. A detailed kinetic reaction scheme is presented to model the experimental reactant and product yield profiles as a function of temperature. The results of modeling showed that the major initiation reaction was the C-C bond fission reaction. The abstraction of the secondary H atom by F atoms was also predicted to be important, whereas 1,2-HF elimination was slower. From experiments and modeling, the following initiation rate constants were obtained: CF3CHFCF3 -> CF3 + CF3CHF (k37 = 1E15.9 exp(-355.6 kJ mol-1/RT) s-1), CF3CHFCF3 -> C3F6 + HF (k38 = 1E12.9 exp(-291.2 kJ mol-1/RT) s-1), and CF3CHFCF3 + F -> CF3CFCF3 + HF (k39 = 1E136 exp(-10.1 kJ mol-1/RT) cm3 mol-1 s-1).
- Hyenes, Robert G.,Mackie, John C.,Masri, Assaad R.
-
-
- Catalytic synthesis of 1,1,1,2-tetrafluoroethane from 1,1,1,2-tetrachloroethane - A mechanistic consideration
-
1,1,1,2-Tetrachloroethane and its fluorinated derivatives as well as trichloroethene are fluorinated by hydrogen fluoride in the presence of a pre-conditioned chromia catalyst. The reaction pathways are derived under different conditions. Fluorinated haloalkanes are formed both by dehydrochlorination/hydrofruorination mechanism as well as chlorine/ fluorine exchange mechanism. Thus, beside fluorinated alkanes considerable amounts of haloolefins occur in the product mixture. A survey is given on the reaction pathway showing dependence on the reaction conditions. It is discussed with respect to calculated thermodynamic data. Kinetic and mechanistic investigations of the isomerisation reactions of 1.1.2.2-tetrafluoroethane on a CFC-conditioned chromia catalyst are also presented. The desired 1.1.1.2- tetrafluoroethane can be obtained from its symmetric isomer in the presence of a chromia catalyst conditioned exclusively with chlorine-free fluorocarbons. Mechanistic information is obtained by employing DCl which behaves similar to HF during the consecutive isomerisation reaction of 1.1.2.2- tetrafluoroethane. Thus, it is most probable that dehydrohalogenation/hydrohalogenation processes (elimination/addition mechanism) are mainly responsible for the formation of the haloolefins and halocarbons observed on chromia.
- Kemnitz,Niedersen,Kohne
-
p. 485 - 493
(2007/10/03)
-
- Mechanistic aspects of the isomerization reactions of 1,1,2,2-tetrafluoroethane on a CFC-conditioned chromia catalyst
-
The mechanism of the isomerization reactions of 1,1,2,2-tetrafluoroethane on a CFC-conditioned chromia catalyst was investigated. The desired 1,1,1,2-tetrafluoroethane can be obtained from its symmetric isomer in the presence of a chromia catalyst conditioned exclusively with chlorine-free fluorocarbons. In the presence of chlorofluorocarbons, hydrogen chloride is formed as a result of the decomposition reactions of the haloalkane used and is strongly adsorbed on to the surface. This HCl causes a very complex system of side-reactions. In addition, a second kind of chlorine, inactive chloride bonded to chromium, is formed which can only be removed as the result of a very slow solid-gas reaction. Mechanistic information was obtained by examining the effects of substituting DCl for HCl as the chlorine source for the reaction with consecutive isomerization products of 1,1,2,2-tetrafluoroethane. Thus, it is most probable that dehydrohalogenation/hydrohalogenation processes (elimination/addition mechanism) are mainly responsible for the formation of the halo-olefins and halocarbons observed on chromia. As the HCl/DCl adsorbed on the surface is very quickly removed by the reactions with the halocarbons and halo-olefins, it is advantageous to employ pulse techniques to evaluate this reaction system.
- Kemnitz,Niedersen
-
p. 111 - 119
(2007/10/03)
-
- 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
-
p. 167 - 173
(2007/10/03)
-
- THERMAL AND THERMOOXIDATIVE STABILITY OF OZONE-SAFE FREONS
-
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.
-
p. 1880 - 1890
(2007/10/03)
-
- 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.
-
p. 1935 - 1940
(2007/10/03)
-