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Thermodynamically unstable fluorides of nickel: NiF4 and NiF3 syntheses and some properties
F- acceptors (BF3, AsF5, SbF5, or BiF5) added to solutions of NiF62- salts in anhydrous hydrogen fluoride (aHF) below -65 °C precipitate the tan solid NiF4. This solid, preserved at ≤-65 °C, is quantitatively converted, by 2 equiv of F- donor (XeF6 or KF) in aHF, to dissolved NiF62-. Dry NiF4 loses F2 above -60 °C, the decomposition to nearly black NiF3 becoming rapid at ～0 °C. When the dry NiF4 is prepared from K2NiF6, inclusion of some K+ leads, on thermolysis at 0 °C, to a pyrochlore form of NiF3 (P-NiF3). P-NiF3 contains K+ in the open channels, with KxMiF3, x ≈ 0.1. The nearly cubic P-NiF3 unit cell is rhombohedral: a0 = 9.933(3) A?, α = 91.01(3)°, V = 980 A?3, z = 16, with absent reflections coincident with those of the cubic space group Oh7-Fd3m, appropriate for pyrochlore. Decomposition of NiF4 in aHF begins at -65 °C and is rapid at 0 °C, giving black rhombohedral NiF3 (A-NiF3) with a0 = 5.168(2) A?, α = 55.46(3) A°, V = 87.3 A?3, z = 2. When the NiF4 is made and decomposed at ～20 °C, with K+ present, a hexagonal tungsten bronze form of NiF3 is precipated (H-NiF3), with a0 = 7.074(6) A?, c0 = 7.193(6) A?, V = 312A?3, z = 6. R- and H-NiF3 can also be made by mixing solutions of Ni2+ salts [e.g., Ni(AsF6)2] with NiF62- salts (e.g. K2NiF6) in aHF. All forms of the trifluoride (R, H, and P) lose F2 on warming (R > 39°, H > 72° and P > 138 °C) to yield NiF2, but an intermediate red-brown phase is observed for R-NiF3. R-NiF3 at ～20 °C, oxidizes Xe to Xe(VI), perfluoropropene, C3F6, to perfluoropropane, C3F8, and solid LiCl with incandescence. H-NiF3 and P-NiF3 interact similarly but less energetically.
?emva,Lutar,Chacón,Fele-Beuermann,Allman,Shen,Bartlett
p. 10025 - 10034
(1995)
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Decomposition characteristics of C5F10O/air mixture as substitutes for SF6 to reduce global warming
Sulfur hexafluoride (SF6) is widely used in the power industry but is a serious greenhouse gas. Many researchers committed to achieving sustainable development of the power industry are finding alternatives to SF6 gas. C5F10O performs well in terms of environmental protection, insulation, and safety and is a potential environment-friendly alternative gas. In this paper, the insulation and decomposition characteristics of C5F10O/air gas mixture were examined using gas-insulation performance test platform, and decomposition products were detected by gas chromatography–mass spectrometry. The formation mechanism and distribution of C5F10O decomposition products were analyzed through reactive molecular dynamics method and density functional theory. The influence of air on the decomposition of C5F10O was also evaluated. Results showed that the decomposition of C5F10O/air gas mixture mainly produces CF3[rad], C3F7[rad], C4F7O[rad], CO, CF2[rad], CF[rad], F[rad] and CF4. The breakdown voltage of C5F10O/air gas mixture decreased slightly after repeated breakdown tests, and CF4, C2F6, C3F8, C3F6, C4F10, CF2O were detected. These results can serve as a reference for the systematic comprehension of the decomposition characteristics of C5F10O/air gas mixture and for related engineering applications.
Li, Yi,Zhang, Xiaoxing,Xiao, Song,Chen, Qi,Wang, Dibo
p. 65 - 72
(2018/02/14)

Method for performing olefin addition reaction by using microchannel reactor
The present invention discloses a method for carrying out addition on olefin and fluorine gas by using a microchannel reactor, wherein C2-C9 olefin or fluoroolefin reacts with F2 in a microchannel reaction module to obtain the corresponding fluoroalkane. According to the present invention, with the method, the purity of the prepared fluoroalkane is high, and the method has the cost advantage.
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Paragraph 0060; 0061; 0062; 0063; 0064

(2017/03/14)

Preparation of trifluoroiodomethane via vapour-phase catalytic reaction between pentafluoroethane and iodine
A new route for preparing C33I has been developed via a reaction between C2HF5 and I2. The influence of reaction temperature and active components of the catalysts on the amount of C33I was investigated. The result suggests that the selectivity of the C33I can be controlled by reaction conditions and active component of catalyst. The process for the formation of C33I and by-products is also discussed.
Mao, Aiqin,Wang, Hua,Tan, Linhua,Nin, Xiangyang,Pan, Renming
p. 4640 - 4642
(2013/07/19)

Catalytic pyrolysis of CHF3 over activated carbon and activated carbon supported potassium catalyst
The catalytic activity of activated carbon (AC) and activated carbon supported potassium for the decomposition of CHF3 was investigated at temperatures between 873 and 1173 K and at a space velocity of 4300 h -1. It is found that activated carbon supported potassium shows high and relatively stable activity during the pyrolysis of CHF3 under the conditions studied. Compared with the gas phase reaction, the conversion of CHF3 increases by up to 10 times between 873 and 1123 K, with the major products being C2F4 and C3F6. Selectivities as high as 55% to C2F4 and 35% to C 3F6 are achieved under optimum conditions. The main byproduct HF readily reacts with K2O in the catalyst, converting the catalyst from K2O/AC into KF/AC. Selectivity to the major products remains relatively constant following this transformation.
Han, Wenfeng,Kennedy, Eric M.,Liu, Huazhang,Li, Ying,Adesina, Adesoji A.,MacKie, John C.,Dlugogorski, Bogdan Z.
scheme or table
p. 698 - 703
(2010/09/12)

Depolymerization of Fluoropolymers
A process for depolymerizing fluoropolymers includes continuously feeding a solid fluoropolymer, in particulate form, into a horizontal cylindrical first reaction zone. The fluoropolymer particles enter the first reaction zone at one end. Within the first reaction zone, a central axle from which protrudes at least one paddle, continuously rotates. The rotating paddle serves to advance the fluoropolymer particles along the reaction zone while agitating them. As the fluoropolymer particles pass along the reaction zone, they are subjected to an elevated temperature, thereby depolymerizing the fluoropolymer into a fluoro-containing compound-rich gas phase. A residual solids phase is withdrawn at the other end of the first reaction zone, as is the gas phase. Optionally, the gas phase is passed through a second reaction zone which is also at an elevated temperature. The gas phase is quenched, thereby to recover the fluoro-containing compounds as gaseous products.
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Page/Page column 4-5

(2009/06/27)

Investigation of CF2 carbene on the surface of activated charcoal in the synthesis of trifluoroiodomethane via vapor-phase catalytic reaction
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.
Yang, Guang-Cheng,Lei, Shi,Pan, Ren-Ming,Quan, Heng-Dao
experimental part
p. 231 - 235
(2009/08/07)

PRODUCTION PROCESSES FOR MAKING 1,1,1,2,2,3-HEXAFLUOROPROPANE
A process for making HFC-236cb is disclosed. The process comprises reacting TFE with HFC-32 in the presence of at least one co-product and a suitable catalyst to produce a product mixture comprising HFC-236cb, wherein the total amount of the at least one co-product is at least 10 ppmv based on the total amount of the tetrafluoroethylene, the difluoromethane and the at least one co-product.
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Page/Page column 12-13

(2008/06/13)

CATALYTIC ADDITION OF HYDROFLUOROCARBONS TO FLUOROOLEFINS
A process is disclosed for making RR1R2CCR1R2F wherein R is selected from the group consisting of CH3, CH2F, C2H4F, and F(CF2)nCH2CH2 where n is an integer from 1 to 10, each R1 is independently selected from the group consisting of H, Cl, F and CF3, and each R2 is independently selected from the group consisting of H, F and CF3. The process involves reacting RF with R1R2C=CR1R2 in the presence of SbF5 to produce a product mixture comprising RR1R2CCR1R2F, wherein the reaction temperature is from about -60° C to about -10° C, provided that total number of carbon atoms in R1R2C=CR1R2 is 5 or less.
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Page/Page column 7; 13-14

(2008/06/13)

Adsorbent for purifying perfluorocarbon, process for producing same, high purity octafluoropropane and octafluorocyclobutane, and use thereof
To provide a purification adsorbent capable of effectively removing impurities contained in a perfluorocarbon and obtaining a perfluorocarbon reduced in the impurity content to 1 ppm by mass or less; a process for producing the adsorbent; high-purity octafluoropropane or octafluorocyclobutane; processes for purifying and for producing the octafluoropropane or octafluorocyclobutane; and uses thereof. Purification is performed using a purification adsorbent produced by a method comprising (1) washing an original coal with an acid and then with water, (2) deoxidizing and/or dehydrating the original coal, (3) re-carbonizing the original coal at a temperature of from 500 to 700° C. and (4) activating the original coal at a temperature of from 700 to 900° C. in a mixed gas stream containing an inert gas, carbon dioxide and water vapor.
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Page/Page column 12-14

(2008/06/13)

Synthesis of perfluoroalkanes in high-temperature fluorination of graphite with fluorine in a reactor with a free-falling graphite bed
Reaction between fluorine and graphite in a reactor with a free-falling bed of graphite was studied in relation to the temperature in the reaction zone, ratio of the feeding rates of fluorine and graphite, and dilution of fluorine with an inert gas. Pleiades Publishing, Inc., 2006.
Shelopin,Pashkevich,Alekseev,Mukhortov,Petrov,Asovich
p. 1031 - 1034
(2008/02/05)

Synthesis of perfluoroalkanes by high-temperature reaction of graphite with fluorine in a fluidized bed
Synthesis of lower perfluoroalkanes (tetrafluoromethane, hexafluoroethane, octafluoropropane, decafluorobutane) by high-temperature reaction of graphite with fluorine in a fluidized bed was studied.
Pashkevich,Shelopin,Mukhortov,Petrov,Alekseev,Asovich
p. 1847 - 1853
(2007/10/03)

Processes for the purification and use of 2-chloro-1,1,1,2,3,3,3-heptafluoropropane and zeotropes thereof with HF
A process is disclosed for the separation of a mixture of HF and CF3CClFCF3. The process involves placing the mixture in a separation zone at a temperature of from about ?30° C. to about 100° C. and at a pressure sufficient to maintain the mixture in the liquid phase, whereby an organic-enriched phase comprising less than 50 mole percent HF is formed as the bottom layer and an HF-enriched phase comprising more than 90 mole percent HF is formed as the top layer. The organic-enriched phase can be withdrawn from the bottom of the separation zone and subjected to distillation in a distillation column to recover essentially pure CF3CClFCF3. The distillate comprising HF and CF3CClFCF3can be removed from the top of the distillation column while essentially pure CF3CClFCF3can be recovered from the bottom of the distillation column. The HF-enriched phase can be withdrawn from the top of the separation zone and subjected to distillation in a distillation column. The distillate comprising HF and CF3CClFCF3can be removed from the top of the distillation column while essentially pure HF can be recovered from the bottom of the distillation column. If desired, the two distillates can be recycled to the separation zone. Also disclosed are compositions of hydrogen fluoride in combination with an effective amount of CF3CClFCF3to form an azeotrope or azeotrope-like composition with hydrogen fluoride. Included are compositions containing from about 38.4 to 47.9 mole percent CF3CClFCF3. Also disclosed are processes for producing 1,1,1,2,3,3,3-heptafluoro-propane. One process uses a mixture comprising HF and CF3CClFCF3and is characterized by preparing essentially pure CF3CClFCF3as indicated above, and reacting the CF3CClFCF3with hydrogen. Another process uses an azeotropic composition as described above, and reacts the CF3CClFCF3with hydrogen in the presence of HF. Also disclosed is a process for producing hexafluoropropene. This process is characterized by preparing essentially pure CF3CClFCF3as indicated above, and dehalogenating the CF3CClFCF3.
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Page column 7

(2008/06/13)

The Reaction of 2-X-1,2-Difluoroalk-1-enyldifluoroboranes with Xenon Difluoride. A Methodical Approach to 1,2-Difluoroalk-1-enylxenon(II) Salts
2-X-1,2-Difluoroalk-1-enylxenon(II) salts were prepared by the reaction of XeF2 with XCF=CFBF2 (X = F, trans-H, cis-Cl, trans-Cl, cis-CF3, cis-C2F5) but no organoxenon(II) compounds were obtained when the trans-isomers of boranes, trans-XCF=CFBF 2 (X = CF3, C4F9, C 4H9, Et3Si), were used under similar conditions.
Frohn, Hermann-Josef,Adonin, Nicolay Yu.,Bardin, Vadim V.
p. 2499 - 2508
(2008/10/09)

Electrochemical fluorination of unsaturated sulfides and sulfones
Electrochemical fluorination of some unsaturated sulfides and sulfones and their reactions with anhydrous HF were studied.
Grigor'eva,Shainyan,Kaurova,Gracheva,Lesnevskaya,Barabanov
p. 1095 - 1100
(2007/10/03)

Cleavage path way and the product distribution pattern during the electrochemical perfluorination of tripropylamine
The electrochemical fluorination (ECF) of tripropylamine (TPA) was carried out in anhydrous hydrogen fluoride medium using a Simons type cell. Under optimum conditions, yield of perfluorinated product was about 51% and the selectivity of perfluorotripropy
Velayutham,Jayaraman,Noel,Krishnamoorthy,Sartori
p. 21 - 26
(2007/10/03)

Electrochemical fluorination of aliphatic secondary amines
Electrochemical fluorination (ECF) has been examined for six aliphatic secondary amines: N,N-di-ethylamine, N-ethyl,N-n-propylamine, N,N-di-n-propylamine, N-ethyl,N-iso-propylamine, N,N-di-iso-propylamine, and N-methyl,N-n-butylamine. It was found from these amines that not only the corresponding F-(N-fluoro-N,N-dialkylamines) but also F-imines having the same number of the carbon atoms were formed in low yields. The suppression of the C-N bond cleavage (blocking effect) which is expected to occur during fluorination due to the presence of bulky N-alkyl group was not observed as a result of the ECF of these aliphatic secondary amines. It was also found that the change of the initial solute concentration of N,N-di-n-propylamine did not affect on the product yields, which is usually observed for cyclic secondary amines. Several F-(N-fluoro-N,N-dialkylamines) were treated with triphenylphosphine for conversion into the corresponding F-imines. An imine bond was generated during this defluorination exclusively at the site of the alkyl group with a longer chain length when there were two different alkyl groups present in F-(N-fluoro-dialkylamines).
Abe, Takashi,Hayashi, Eiji,Baba, Hajime
p. 35 - 42
(2007/10/03)

The synthesis of perfluoroamine using nitrogen trifluoride
The reactions of nitrogen trifluoride (1) with hexafluoropropene (2) in the presence of cesium fluoride (CsF) gave 2- (3) and 1-heptafluoropropyldifluoroamine (4) in moderate yields. Tetrafluoroethylene (6) and octafluoro-2-butene (8) similarly reacted with 1 to give corresponding products.
Takagi, Toshiyuki,Tamura, Masanori,Shibakami, Motonari,Quan, Heng-Dao,Sekiya, Akira
p. 15 - 17
(2007/10/03)

Technology for the preparation of perfluoro-organic compounds
Fluorination by elemental fluorine of fluorine-containing alkenes, alkanes, ethers and tertiary amines was investigated, aimed at obtaining the perfluorinated analogs. The factors affecting yield of the target compounds were studied. Elements of technology were elucidated.
Moldavskii, Dmitrii D.,Bispen, Tatjana A.,Kaurova, Galina I.,Furin, Georgii G.
p. 157 - 167
(2007/10/03)

vic-difluorination of fluoroalkenes with xenon difiuoride: The effect of fluorine substituents on the reaction of alkenes with xenon difluoride
vic-Difluorination proceeds by the reaction of fluoroalkenes with xenon difluoride to afford the corresponding fluorinated compounds. From the reaction with polyfluoroalkenes, the products are obtained in high to excellent yields. In this reaction, the fluorine atom substituent of alkene stabilizes the cation intermediate and suppresses side-reactions such as rearrangement.
Tamura, Masanori,Quan, Heng-Dao,Sekiya, Akira
p. 3151 - 3153
(2007/10/03)

Production of perfluorinated organic compounds
Fluorination of a series of perfluoroolefins and their alkoxy and diethylamino derivatives with elemental fluorine in the gas and liquid phases was studied. The possibility of fluorinating these compounds with pure fluorine was demonstrated. The fluorination parameters were determined, and separate stages of processes for preparing a series of practically important products were developed. The heats of fluorination of the compounds studied were calculated.
Bispen,Moldavskii,Furin
p. 1409 - 1417
(2007/10/03)

Synthesis of perfluorinated paraffins, esters, and tertiary amines by direct fluorination with elemental fluorine
Fluorination of partially fluorinated olefins, paraffins, ethers, and tertiary amines with elemental fluorine at the gas-liquid interface under various conditions was studied.
Bispen,Moldavskii
p. 1009 - 1013
(2007/10/03)

The dark reactions F2 + CF3I, C2F5I, and n-C3F7I
The reactions between F2 and the lowest members of the homologous series of perfluoroalkyl iodides (CF3I, C2F5I, and n-C3F7I) have been studied. For these compounds, an exponential decrease
Johnson,Walters,Dorko
p. 43 - 55
(2007/10/03)

Die elektrochemische fluorierung von alkansulfonamiden und alkandisulfonamiden
Alkane sulphonylamides and disulphonylamides are stable in anhydrous (HF)x and undergo quantitative fission of S-N bonds during electrochemical fluorination. Besides NF3, the corresponding perfluoroalkane sulphonyl fluorides and disulphonyl fluorides are formed.
Satori,Juenger
p. 71 - 75
(2007/10/03)

Some chemistry of high oxidation state transition metal fluorides in anhydrous HF
The salt AgFIrF6 (AgIrF6 + 1/2F2 in AHF) is isostructural with AgFAsF6.Failure to prepare AgFOsF6 (AgOsF6 + F2 -> AgF2 + OsF6) indicates that the one-dimensional chain cation (AgF)n+1n takes the electron from OsF6(1-).The Ag(2+)(solv) ion oxidizes IrF6(1-) to IrF6 and at -78 deg C in AHF, O2 to O(1+)2 (O2 + Ag(2+) + 2AsF6(1-) -> O(1+)2AsF6(1-) + AgAsF6).This reaction is negligible at ca. 20 deg C because of the loss of translational entropy that accompanies the formation of the crystalline products.Dissolution of AgF3 in AHF with A (A = AsF5, SbF5 or BiF5) gives a solution (solv)> which oxidizes PtF6(1-) or RuF6(1-) to MF6 and O2 to O(1+)2.K2NiF6 in AHF below -60 deg C with greater than threefold molar excess of BF3 yields yellow-brown solutions (solv)> which also oxidize PtF6(1-) or RuF6(1-) to MF6.The species Ag(III)(solv) and Ni(IV)(solv) in AHF are oxidizers of unsurpassed power. - Keywords: Anhydrous hydrogen fluoride; Nickel hexafluoride salts; Silver tetrafluoride salts; Oxidizing power; Reactivity
Lucier, G.,Shen, C.,Casteel, W. J.,Chacon, L.,Bartlett, N.
p. 157 - 164
(2007/10/02)

FLUORINATION OF ORGANIC COMPOUNDS IN THE PRESENCE OF HEXAFLUOROPROPYLENE OLIGOMERS
Unsaturated perfluorinated compounds, polyfluorinated ethers, and aromatic and heterocyclic compounds were fluorinated by fluorine in the hexafluoropropylene trimer.A mechanism including the formation of the stable C9F19 radical is proposed.
Zabolot-skikh, V. F.,Kochanov, A. S.,Tiunov, A. V.,Markin, I. V.
p. 1282 - 1283
(2007/10/02)

DIRECT GAS-PHASE CATALYTIC FLUORINATION OF PARTIALLY FLUORINATED ORGANIC COMPOUNDS
The fluorination of a wide range of polyfluorinated organic compounds with molecular fluorine in the gas phase in a layer of NiF2/support as catalyst was investigated.It was shown that the selectivity of fluorination of the series of fluoroolefins, acid fluorides, polyfluoroalkanes, and hydrogen-containing ethers can be greatly increased.The developed method was used on an industrial scale in the production of perfluorinated liquids.
Zakharov, V. Yu.,Denisov, A. K.,Novikova, M. D.
p. 1942 - 1945
(2007/10/03)

MACROKINETIC FEATURES OF HEXAFLUOROPROPYLENE FLUORINATION BY COBALT TRIFLUORIDE
A study has been made of some macrokinetic features of hexafluoropropylene fluorination by cobalt trifluoride.The method has been proposed for studying the nonstationary processes occurring in a plug-flow reactor, and the effectiveness of this method has been shown.The limiting stage of the process and the features of its variation with temperature have been determined.A mathematical model of the process has been developed, and parameters of this model have been estimated.
Asovich, V. S.,Kostyaev, R. A.
p. 1163 - 1166
(2007/10/02)

Perfluorination of Allene Derivatives by Direct Fluorination
Perfluoropropane was prepared from allene with elemental fluorine in the presence of sodium fluoride in 84percent yield for the first time.The reaction of allene with elemental fluorine afforded 2,2-difluoropropane in the absence of sodium fluoride.Methoxyallene and cyanoallene were perfluorinated with elemental fluorine in the presence of sodium fluoride to give heptafluoropropyl trifluoromethyl ether and heptafluoropropyl cyanide in good yields respectively.In addition, the direct fluorination of cyanoallene in the presence of cesium fluoride afforded N,N-difluorononafluorobutylamine in 95percent yield.
Arimura, Takashi,Shibakami, Motonari,Tamura, Masanori,Kurosawa, Shigeru,Sekiya, Akira
p. 588 - 598
(2007/10/02)

THE DIRECT FLUORINATION OF ACETONE
A synthesis for hexafluoroacetone using elemental fluorine is reported.Previously hexafluoroacetone and other ketones have been difficult to prepare using fluorination based syntheses.
Clark, Wayne D.,Lagow, Richard J.
p. 37 - 43
(2007/10/02)

REACTIONS OF TeF5OCl WITH FLUOROCARBON IODIDES AND SYNTHESIS OF CF3OTeF5
The low temperature reaction of TeF5OCl with the fluorocarbon iodides, CF3I, C2F5I, n-C3F7I, and i-C3F7I results in the formation of RfI(OTeF5)2 adducts.Except for the trifluoromethyl derivative these are stable, colorless compounds.The trifluoromethyl adduct decomposes above -78 deg C to give the previously unknown CF3OTeF5.The perfluoroethyl and n-propyl adducts decompose at 120 deg C or under UV radiation giving C2F5OTeF5 and n-C3F7OTeF5, respectively.These reactions constitute a new synthesis of primary RfOTeF5 compounds.Attempts to extend this synthesis to secondary fluorocarbon iodides were unsuccessful.
Schack, Carl J.,Christe, Karl O.
p. 79 - 87
(2007/10/02)

CURRENT BALANCE OF THE ELECTROCHEMICAL FLUORINATION OF A TRIALKYLAMINE
The electrochemical fluorination of dibutylmethylamine was studied.All the fluorination products formed, liquid, gaseous, and dissolved in HF, and also the hydrogen evolved were quantitatively determined.From either their formulae or their relative fluorine contents the amount of current necessary for their formation was estimated.Altogether, the fluorination products determined cover about 86-97 percent of the current applied.A major part of the current was consumed by production of polyfluorinated products, which remained dissolved in the hydrogen fluoride.
Dimitrov, A.,Stewig, H.,Ruediger, St.,Kolditz, L.
p. 13 - 22
(2007/10/02)

Photoinduced Fluorination of Hexafluoropropene Trimers: Synthesis of Branched Perfluoroalkanes
Hexafluoropropene trimers, perfluoro-3-ethyl-2,4-dimethylpent-2-ene (1) and perfluoro-3-isopropyl-4-methylpent-2-ene (2) reacted with fluorine under u.v. irradiation to give the new and highly branched perfluoroalkanes perfluoro-2,3,3,4-tetramethylpentane (7) and perfluoro-2,3,4-trimethylpentane (8) through a mechanism involving the elimination-readdition of CF3 groups.Compound (7), which is very bulky, can be easily cleaved at 200 deg C to give two perfluoro radicals capable of initiating the polymerization of vinylic monomers.
Tonelli, Claudio,Tortelli, Vito
p. 23 - 26
(2007/10/02)

The infrared multiphoton dissociation of hexafluoroethane
The infrared multiphoton dissociation (IRMPD) of "neat" hexafluoroethane has been investigated for the first time.The stable products of photolysis are CF4, C2F4, C3F8, and C4F10.Product analysis involved tunable diode laser (TDL) and fourier transform infrared spectroscopy, as well as gas chromatography where applicable.The high sensitivity and resolution of the TDL allows for measurement of the stable products CF4 and C2F4 after irradiation by a single infrared laser pulse.The yield of CF3 radicals produced by the IRMPD of C2F6 as a function of fluence was measured via the TDL high frequency modulation technique.The role of added H2, leading to elimination of CF4 and increase of C2F4 as products, is clarified.
Brown, Carl E.,Smith, Donald R.
p. 609 - 614
(2007/10/02)

SYNTHESIS OF PENTAFLUOROSELENIUMOXIDE FLUOROCARBONS
The reaction of xenon bis-pentafluoroseleniumoxide, Xe(OSeF5)5, with the haloolefins, CF2=CF2, CF3CF=CF2, CF2=CFCl, and CF2=CFH, results in the low to moderate yield addition of two SeF5O- groups to the double bond.These are the first examples of this type of addition.From c-C5F8 and the above olefins these same reactions also gave as products, C2F5OSeF5, n-C3F7OSeF5, c-C5F9OSeF5, and SeF5OCF2COCl in higher yields than the bis SeF5O- compounds.Surprisingly, those olefins capable of forming thermally stable epoxides, i.e.C3F6 and c-C5F8, were found to produce significant yields of the corresponding epoxides as a by-product in these reactions, while the remaining olefins gave significant amounts of acid fluorides instead.Characterizing data are presented for all of these new RfOSeF5 compounds.
Schack, Carl J.,Christe, Karl O.
p. 163 - 172
(2007/10/02)

The Fluoro(perfluoroalkylnitrile)noble-gas(II) Cations, RFCN-NgF+ (Ng = Kr or Xe; RF = CF3, C2F5, n-C3F7), and the Fluoro(trifluoro-s-triazine)xenon(II) Cation, s-C3F3N2N-XeF+; Novel Noble Gas-Nitrogen Bonds
Three novel examples of Kr-N bonds derived from perfluoroalkylnitriles, the RFCN-KrF+ cations, and their xenon analogues RFC-XeF+ (RF = CF3, C2F5, n-C3F7), have been prepared and characterized i
Schrobilgen, Gary J.
p. 1506 - 1508
(2007/10/02)

ELECTROCHEMICAL FLUORINATION USING POROUS NICKEL AND FOAM NICKEL ANODES
This work set out to examine the reasons behind some of the problems associated with ECF, namely, lack of reproducibility, low chemical yields, poor selectivity and low current densities, with a view to ameliorating these shortcomings and making the process more attractive to the chemical industry.The approach was to study the chemistry under controlled conditions of potential, reactant concentration, temperature, etc., and to analyse the results in terms of product structure, distribution and yield.Two distinct stages in the process were identified, i) the conditioning of the electrode, and, ii) the fluorination of the organic substrate.These stages are described in detail in relation to two model systems investigated, the fluorination of propene using porous and foam nickel anodes, and the fluorination of the octanoyl chloride using nickel foam anodes.The scales of experiments ranged from 100 ml to 100 l cell capacities.General conclusions are derived and recommendations made for the more efficient operation of the process.
Drakesmith, F. G.,Hughes, D. A.
p. 103 - 134
(2007/10/02)

CO2 LASER-INDUCED AND BCl3-SENSITIZED DECOMPOSITION OF HEXAFLUOROACETONE. COMPARISON WITH HIGH TEMPERATURE THERMOCHEMISTRY
The cw CO2 laser-induced decomposition of hexafluoroacetone sensitized with boron trichloride (total pressure 5.3-8.0 kPa) yields along with perfluorinated hydrocarbons trifluoroacetyl fluoride, carbon monooxide and carbonyl fluoride.The same carbonyl compounds are also formed by conventional thermal decomposition of hexafluoroacetone on tungsten filament at tempetratures 950-2100 deg C but their distribution during reaction progress is different.Features of both reactions are discussed.
Pola, Josef,Engst, Pavel,Horak, Milan
p. 912 - 917
(2007/10/02)

Reactions involving Fluoride Ion. Part 23. Thermolytic Defluorination of Perfluoroalkenes in the Synthesis of Fluorinated Dienes and Cyclobutenes
Passage of perfluoro-3,4-dimethylhex-3-ene over iron or platinum at elevated temperatures leads to defluorination and fragmentation, giving fluorinated dienes, e.g. perfluoro-2,3-dimethylbutadiene (over Pt) and perfluoro-3,4-dimethylhexa-2,4-diene (over Fe), together with other products.Similar reactions with other fluorinated alkenes and the variation between fragmentation and fluorination is rationalised on the basis of the metal used, etc.The fluoride induced reaction between perfluoropropene and perfluorobut-2-ene gives perfluoro-2,3-dimethylpent-2-ene.
Chambers, Richard D.,Lindley, Andrew A.,Fielding, Harold C.,Moilliet, John S.,Whittaker, Graham
p. 1064 - 1067
(2007/10/02)

Reaction of N-Chloro-N-fluoroperhaloalkylamines with Mercury. Facile Synthesis of N-Fluoro Imines and N-Fluoro Amines
The reaction of N-chloro-N-fluoroalkylamines with mercury has been studied with ClCF2NClF, CF3NClF, CF3CF2NClF, CF3CF2CF2NClF, and (CF2NClF)2.In the absence of solvents, all but CF3NClF undergo dehalogenation to form the corresponding N-fluoro imines in good yield.Only the syn isomers of CF3CF=NF, CF3CF2CF=NF, and (CF=NF)2 are observed.With trifluoroacetic acid as a solvent, the reactions with mercury yield the corresponding N-fluoro amines ClCF2NHF, CF3NHF, CF3CF2NHF, and CF3CF2CF2NHF in excellent yields except with (CF2NClF)2.For the latter, the amine (CF2NHF)2eliminates HF under the reaction conditions, and only (CF=NF)2 is isolated.With trifluoroacetic anhydride as a solvent, ClCF2NClF is dehalogenated with mercury to give excellent yields of CF2=NF in the first practical synthesis of this simplest perfluoro imine.Details of these reactions and the characterization of the new compounds ClCF2NHF, CF3CF2NHF, CF3CF2CF2NHF, and CF3CF2CF=NF are presented.
Sekiya, Akira,DesMarteau, Darryl D.
p. 1277 - 1280
(2007/10/02)

Product distributions and isotopic selectivities in ir multiphoton dissociation of pentafluoroiodoethane
Infrared multiphoton dissociation of pentafluoroiodoethane leads to a complex array of reaction products.For photolysis in the ν4 band the reaction mechanism involves C2F5-I bond cleavage followed by thermal dissociation of C2F5 radicals.For irradiation within the ν3 band at high fluence, efficient secondary photolysis of C2F5 radicals is postulated.At lower fluences the dissociation is isotopically selective leading to C4F10 enriched in carbon-13.
Weinberg, E.,Gauthier, M.,Hackett, P. A.,Willis, C.
p. 1307 - 1310
(2007/10/02)

IR MATRIX ISOLATION SPECTRA OF SOME PERFLUORO ORGANIC FREE RADICALS PART III. n-C3F7 and iso-C3F7
The perfluoro radicals n-C3F7 and iso-C3F7 have been prepared by pyrolyzing the corresponding iodides in a platinum effusion tube at temperatures between 450-550 deg C and isolated in argon matrices.By eliminating absorption bands attributed to known fluorine compounds and applying relative absorption band intensity correlations, several absorption bands have been assigned, some 30 to n-C3F7 and 29 to iso-C3F7, in the spectral range 2000-200 cm-1.A tentative vibrational assignment is presented for both species on the assumption of Cs symmetry.Some thermodynamic implications of the findings are also dicussed.
Butler, R.,Snelson, A.
p. 33 - 50
(2007/10/02)

GAS PHASE RADIATION CHEMISTRY OF HEXAFLUOROETHANE
The Co-60 gamma radiolysis of gaseous C2F6 was investigated at 50 Torr pressure, both pure and with 10percent oxygen added.For the pure system, the radiolytic products and their respective G values were CF4, 2.27; C3F8, 0.23; C4F10, 0.09; C5F12, 0.015; and C6F14, 0.009.All radiolysis products except for CF4 (C = 0.61) were eliminated when 10percent O2 was added as scavenger.The results are discussed mainly in terms of the decomposition of excited C2F6 into free radicals, which can then combine.The unscavenged CF4 is accounted for by the ion-molecule reaction CF3+ + C2F6 -> CF4 + C2F5+.
Scanlon, Michael D.,Hanrahan, Robert J.
p. 199 - 208
(2007/10/02)

Synthesis of Perfluoroalkyl Trifluoromethanesulfonates from Perfluoroalkyl Halides. Substitutive Electrophilic Dehalogenation with Chlorine(I) and Bromine(I) Trifluoromethanesulfonates
The reactions of chlorine(I) and bromine(I) trifluoromethanesulfonates with a variety of perfluoroalkyl halides are reported.The reactions form Br2, Cl2, or BrCl and the corresponding trifluoromethanesulfonate derivatives of the alkyls in good yields.Twelve new esters are reported and characterized.An SEi-type mechanism for the reactions is proposed with complete retention of configuration by the alkyl on substitution.
Katsuhara, Yutaka,DesMarteau, Darryl D.
p. 2681 - 2686
(2007/10/02)

Process for the manufacture of octafluoropropane
Octafluoropropane, C3 F8, is prepared by a two-step process. In the first step hexafluoropropene is reacted with hydrogen fluoride in the presence of a chromium oxyfluoride catalyst. The 2H-heptafluoropropane obtained is reacted with fluorine in the presence of a catalyst which contains a subgroup element of the Periodic System as a free metal or as a fluoride. Octafluoropropane is isolated from the resulting gas mixture. Hydrogen fluoride also obtained may be recycled to the first reaction step.
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(2008/06/13)

High-pressure interaction of sulfur hexafluoride with carbon disulfide and carbonyl sulfide
Sulfur hexafluoride has been found to react with carbon disulfide and carbonyl sulfide. At a minimum of 485° (1360 atm) with carbon disulfide the products are (CF3)2S, (CF3)2S2, carbon, and sulfur. Carbonyl sulfide reacts at 500° (270 atm) forming CF4, SOF2, and sulfur. No reaction takes place with carbon monoxide or carbon dioxide at conditions up to 500° (4000 atm). Graphite reacts at 500° (135 atm) forming CF4 and SF4 in a reaction which becomes nearly quantitative at 500° (4000 atm). When (CF3)2S2 is combined with carbon disulfide at 540° (4000 atm) the products include carbon, sulfur, and fluoroalkanes. The observed interaction of CO2, COS, and CS2 with SF6 can be best explained by an initial reaction which results in the formation of SF4, COF2 or CSF2, and sulfur.
Hagen, Arnulf P.,Callaway, Bill W.
p. 2825 - 2827
(2007/12/03)

RAPID CONTINUOUS QUANTITATIVE ANALYSIS OF FLUOROCARBON MIXTURES WITH THE AID OF THE TIME-OF- FLIGHT MASS SPECTROMETER
It is shown, with fluorocarbon mixtures as an example, that the time-of- flight mass spectrometer can be used for rapid continuous quantitative analysis of the products of gaseous reactions. The precision of the method is 8 to 10% for component contents of not less than 20%, and 15 to 18% for component contents below 10%. The sensitivity of the method is of the order of 1 vol. %. The precision and sensitivity achieved can be improved considerably by simple modification of the apparatus.
DYMSHITS BM,KORETSKII YAP,LIR VI,TURKINA MYA,DOBYCHIN SL
p. 2470 - 2475
(2008/10/08)