353-59-3Relevant academic research and scientific papers
Reaction of Atomic Bromine with Difluorochloromethane. The Heat of Formation of the CClF2 Radical and the Do (CClF2-H) Bond Dissociation Energy
Miyokawa, K.,Tschuikow-Roux, E.
, p. 7328 - 7331 (1992)
The gas-phase photobromination of CHClF2 (1) in the presence of CH3Cl (2) as competitor has been studied in the temperature range 80-150 deg C at halomethane pressures of ca. 35 Torr and a Br2 pressure of ca. 2.3 Torr.The temperature dependence of the rate constant ratio is found to obey the Arrhenius expression ln (k1/k2) = (-0.0885 +/- 0.0580) - (1144 +/- 20)/T.This result is combined with an earlier relative study of CH3Cl (2) vs C2H6 (3) and a recent direct determination by kinetic spectroscopy of the rate constant for the bromination of ethane (k3) to obtain absolute rate parameters for the reaction CHClF2 + Br -> CClF2 + HBr.Using a justifiable approximation concerning the magnitude of the activation energy difference for the reverse reactions between any two competitors of similar complexity, and other thermochemical data from the literature, the following quantities have been derived: ΔHfo298(CClF2) = -66.7 +/- 2 kcal mol-1 and Do(CClF2-H) = 100.7 +/- 2 kcal mol-1 where the uncwrtainties are conservative estimates.On the basis of the new value of k3, activation energies for the bromination of CH4 and other halomethanes are reported.
Synthesis process for bromine-containing hydrofluoroalkane
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Paragraph 0030-0032, (2017/05/12)
The invention discloses a synthesis process for bromine-containing hydrofluoroalkane CnH2n+2-x-y-zFxClzBry. In the presence of halogen gas, hydrofluoroalkane and Br2 react to prepare corresponding bromine-containing hydrofluoroalkane. The method provided by the invention is simple in process, high in yield and low in energy consumption, and is suitable for industrial production.
Kinetics of the Reactions of Halogenated Methyl Radicals with Molecular Bromine
Timonen, R. S.,Seetula, J. A.,Niiranen, J.,Gutman, D.
, p. 4009 - 4014 (2007/10/02)
The kinetics of seven reactions of halogenated methyl radicals (CH2Cl, CHCl2, CFCl2, CF2Cl, CF3, CH2Br, and CH2I) with molecular bromine were studied by using a heatable tubular reactor coupled to a photoionization mass spectrometer.Rate constants were measured as a function of temperature, typically between 296 and 532 K.Arrhenius activation energies were found to be small negative values (typically -2 kJ mol-1) for all reactions studied with the exception of that of the CF3 + Br2 reaction (whose activation energy is positive, but which could not determined accurately).The pattern of reactivity among 11 reactions of substituted methyl radicals with Br2 (which includes the 7 reactions studied here and 4 C(H)x(CH3)3-x + Br2 reactions (x = 0-3) studied earlier) has been accounted for by the inductive effect of the substituent atoms or groups.The sum of the Pauling electronegativities of these substituents provides a useful measure of their total inductive effect on the reaction rate constant.
Kinetics and Mechanism of the Gas-phase Thermal Bromination of Difluorochloromethane
Zhdanov, G. F.,Poluektov, V. A.,Belevtsev, E. G.,Orlov, G. D.
, p. 39 - 42 (2007/10/02)
We have studied the kinetics of the gas-phase thermal bromination of difluorochloromethane in the dynamic regime at 613-693 K.The form of the kinetic equation has been established for conversions of the difluorochloromethane not greater than 20percent.The absolute value of the rate constant of the bromination reaction has been determined.The energy of the C-H bond in difluorochloromethane has been calculated.
PREPARATION OF HALO-F-METHANES VIA POTASSIUM FLUORIDE-HALOGEN CLEAVAGE OF HALO-F-METHYLPHOSPHONIUM SALTS
Burton, D. J.,Shin-Ya, S.,Kesling, H.S.
, p. 89 - 98 (2007/10/02)
Treatment of halo-F-methylphosphonium salts with potassium fluoride and halogen (I2, Br2, ICl, IBr) gives modest yields of halo-F-methanes.This method of preparation augments the classical Hunsdiecker approach to these materials.
