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Hydrogen fluoroethane

Chloromethoxy-1,2,2 2-tetrafluoroethane is converted by triethylammonium fluoride or piperidine hydrogen fluoride to fluoromethoxy 1 2,2,2-tetra-fluoroethane in greater than 60% yield Piperidine hydrogen fluoride or butyl-ammonium fluoride can convert methoxy-l-chloro-2,2,2-trifluoroethane to methoxy-1,2,2,2-tetrafluoroethane in 80% yield [79]... [Pg.178]

This report is the second volume in the series Acute Exposure Guideline Levels for Selected Airborne Chemicals. AEGL reports for aniline, arsine, monomethylhydrazine, and dimethylhydrazine were reviewed in the first volume. AEGL documents for five chemicals—phosgene, propylene glycol dinitrate, 1,1,1,2-tetrafluoroethane, 1,1-dichloro-l-fluoroethane, and hydrogen cyanide—are published as an appendix to this report. The subcommittee... [Pg.22]

Chlorofluorocarbon (CFC) replacements have recently been used for their lower stability and because they have carbon-hydrogen bonds, which means that their atmospheric lifetime is expected to be much shorter than those of CFCs. The adsorption properties of l,l,2-trichloro-l,2,2-trifluoroethane (CFC 113) and its replacement compounds, l,l-dichloro-2,2,2-trifluoroethane (HCFC123), 1,1-dichloro-l-fluoroethane (HCFC141b), and l,l-dichloro-l,2,2,3,3-pentafluoropropane (HCFC225ca) on four kinds of activated carbons were investigated. The adsorption isotherms of inhalational anesthetics (halothane, chloroform, enflurane, isoflurane, and methoxyflurane) on the activated carbon were measured to evaluate the action mechanism of inhalational anesthesia. The anesthesia of CFC replacements can be estimated by the Freundlich constant N of the adsorption isotherms (Tanada et al., 1997). [Pg.214]

The second organic fluoride was not made until 20 years later. Fremy (with whom Moissan studied in the 1870 s) generated pure anhydrous hydrogen fluoride for the first time by heating potassium hydrogen fluoride (KHF2). The latter (Fremy s salt) was heated with ethyl potassium sulfate in a platinum apparatus to give fluoroethane.12... [Pg.2]

The hydrofluorination of alkenes with anhydrous hydrogen fluoride has been already described extensively in Houben-Weyl, Vol. 5/3, pp 100-101. In the case of ethene, the yield of fluoroethane increases on raising the temperature (90°C, 20-25 atm), however, the procedure should be carried out at lower temperatures with higher alkenes because of their tendency to polymerize thus, 2-fluoropropane is formed in 60-75% yield at 0-45 C. Similar procedures have been described for 2-fluorobutane, 2-fluoro-2-methylpropane and 2-fluoro-2-methyl-butane from but-l-ene, 2-methylpropene and 2-methylbut-2-ene, respectively.63 Cyclohexene reacts at — 78 C with hydrogen fluoride to give fluorocyclohexane (70%) at 100 C polymerization is observed.59,60 Two equivalents of hydrogen fluoride to allene are taken up at — 70 C, to form 2,2-difluoropropane (50%).64... [Pg.107]

Chlorine can be substituted by hydrogen fluoride and boron trifluoride to yield chlorofluorocarbon compounds. This process is applied for producing 1,1-dichloro-l-fluoroethane (14), which is considered as a replacement for trichlorofluoromethane as a blowing agent for plastic foam.18... [Pg.601]

The addition of hydrogen fluoride to vinyl chloride (19) in the gas phase with activated carbon and boron trifluoride gives l-chforo-l-fluoroethane (90% yield).53... [Pg.610]

If hydrogen fluoride can be eliminated in two different ways, it is always the more acidic hydrogen that leaves preferentially. Hydrogen beta to fluorine is significantly more acidic than when alpha to fluorine.30 Consequently, hydrogen fluoride is eliminated from 1,1,2-tri-fluoroethane (24) to form 1,2-difluoroethene [(EjZ)-25],23 and from l//,2//-hexafluoropropane (26) to preferentially give 1 f/-pentafluoroprop-l-ene (27).24-25... [Pg.93]

The reaction of 1-chloro-l-fluoroethane over copper(II) chloride or alumina at 180°C yields 1,1-difluoroethane and 1,1-dichloroethane.32 The conversion is 70% and the yields of both compounds are 40 and 38 %, respectively. This indicates that only minimal hydrogen chloride formation may occur during this disproportionation. [Pg.287]

The electronic influence of the phenyl groups in l,l-diaryl-2-fluoroethane derivatives weakens the C-F bond resulting in elimination of hydrogen fluoride in the presence of a base. In particular 1,1-diaryl compounds readily lose hydrogen fluoride (see Table 5). [Pg.355]

The hydrofluonnation of alkenes also occurs in the gas phase, generally at somewhat higher temperatures [5]. Fluoroethane is obtained in yields as high as 98% at 100 to 160 °C by reaction in the presence of minor amounts of higher a-olefins [6], and 2-fluoropropane is prepared in greaterthan 90% yield at <50 °C from hydrogen fluoride and propene in the presence of activated carbon [7]... [Pg.54]

The shock tube technique employed in the pyrolytic decomposition of polyfluorohydro-carbons22,27,28 showed that the elimination of molecular hydrogen fluoride is the predominant reaction. Yet, a side process of C—C bond breaking becomes important as the temperature is increased beyond 1300 K. Several fluoroethanes have been found to react by molecular dehydrofluorination in chemical activation process29 and Table 2 summarizes the kinetic parameters for the gas-phase pyrolysis of this type of compound. In the case of 1,1,2-trifluoroethane, three olefin products were obtained (equations 3-5). [Pg.1073]

There are many examples of the addition of hydrogen fluoride to olefinic hydrocarbons. Fluoroethane (1) is prepared by gas-phase hydrofluorination of ethene under pres-... [Pg.308]

Chloro-l fluoroethane (10) is prepared by treating chloroethene with anhydrous hydrogen fluoride ° in the vapor phase at 20-70 C in the presence of a catalyst consisting of active charcoal impregnated with 10-45 % by weight fluorosulfonic acid or with hydrogen fluoride/ titanium(IV) chloride. ... [Pg.313]

An example of the reaction of an alkene with 1,1-dichloroethene in anhydrous hydrogen fluoride is the fiuoroalkylation of cyclohexene to yield l,l-dichloro-2-cyclohexyl-l-fluoroethane. ... [Pg.350]

Derivation Interaction of hydrogen with dichlorodi-fluoroethane. [Pg.1319]

Hexafluorobiacetyl. In the gas phase, hexafluorobiacetyl behaved 169> in the same manner as biacetyl, affording carbon monoxide and hexa-fluoroethane in stoichiometric ratio. However, in the presence of hydrocarbon vapor or in hydrocarbon solution, the disappearance of dione was not accompanied by formation of cleavage products. For example, photolysis (A >3000 A, 65°) of hexafluorobiacetyl in 150 molar excess of 2,3-dimethylbutane until 84% of starting material had disappeared resulted in only 0.5% of carbon monoxide, an equivalent amount of trifluoromethane, and a complex mixture of other products. On the basis of carbonyl and hydroxyl absorption in the infrared, it was assumed that the excited dione abstracted hydrogen from hydrocarbons to give products of photoreduction, photoaddition, etc. Occurrence of H-abstraction in the gas phase is unique. [Pg.39]


See other pages where Hydrogen fluoroethane is mentioned: [Pg.148]    [Pg.105]    [Pg.55]    [Pg.148]    [Pg.126]    [Pg.309]    [Pg.631]    [Pg.155]    [Pg.285]    [Pg.309]    [Pg.55]    [Pg.523]    [Pg.105]    [Pg.20]    [Pg.37]    [Pg.47]    [Pg.313]    [Pg.55]    [Pg.129]    [Pg.188]    [Pg.130]    [Pg.131]    [Pg.98]    [Pg.103]    [Pg.313]    [Pg.130]    [Pg.131]    [Pg.28]    [Pg.336]   
See also in sourсe #XX -- [ Pg.81 , Pg.82 , Pg.84 , Pg.85 , Pg.88 , Pg.89 ]




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