tribromomethyl | 4471-18-5

• 分子结构分类: 有机化合物 - 有机卤素化合物 - 有机溴化物
• 英文名称: tribromomethyl
• CAS: 4471-18-5
• 化学式: CBr₃
• 分子量: 251.723
• InChiKey: ROWMQJJMCWDJDT-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.8
• 重原子数：
  4
• 可旋转键数：
  0
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.0
• 拓扑面积：
  0
• 氢给体数：
  0
• 氢受体数：
  0

反应信息

• 作为反应物：
  描述：

  tribromomethyl 在 Li 作用下， 以 solid matrix 为溶剂， 生成 dibromocarbene
  参考文献：
  名称：

  Reactions of Alkali‐Metal Atoms with Carbon Tetrabromide. Infrared Spectra and Bonding in the Tribromomethyl Radical and Dibromocarbene in Solid Argon

  摘要：

  Simultaneous condensation at 15°K of beams of lithium atoms and carbon tetrabromide diluted in argon produces infrared absorptions which are identified as lithium bromide and the tribromomethyl radical. Comparisons within the series of radicals CCl3, CCl2Br, CClBr2, and CBr3 verify the molecular identity. Assignments to the carbon–bromine stretching vibrations are ν1 = 582 cm−1 and v3 = 773 cm−1, whereas the bending modes v2 and v4 were not observed. The stretching force constants Fr = 3.55 mdyn/Å and Frr = 0.70 mdyn/Å are compared with those of other bromocarbons and BBr3. The high carbon–bromine stretching-force constant can be rationalized by the fact that the tribromomethyl radical is resonance stabilized. Secondary reaction of lithium atoms with the tribromomethyl radical yields a sufficient concentration of dibromocarbene for infrared spectral study. Variation of the perbromochloromethane precursors and loss of CBr2 absorptions with attendant growth of the most intense C2Br4 absorption on sample warming furnish convincing evidence that dibromocarbene is isolated in the argon matrix. Assignments to the carbon–bromine stretching vibrations are v1 = 595.0 cm−1 and v3 = 640.5 cm−1, and the bending mode was not detected. The stretching-force constants Fr = 2.38 mdyn/Å and Frr = 0.18 mydn/Å indicate that C–Br single bonds are present in dibromocarbene, making it unlikely that the electron deficiency of the carbon atom is relieved by pi bonding with bromine.

  DOI：

  10.1063/1.1670158
• 作为产物：
  描述：

  三溴甲烷 在 氯 作用下， 生成 tribromomethyl
  参考文献：
  名称：

  Absolute Rate Constants for the Reactions of Cl Atoms with CH₃Br, CH₂Br₂, and CHBr₃

  摘要：

  The rate constants for the reactions of chlorine atoms with the complete series of the three bromomethanes CH3Br (1), CH2Br2 (2), and CHBr3 (3) were measured in a very low pressure reactor, employing a microwave discharge for the generation of Cl atoms with mass spectrometric detection of reactants and products. The experiments were performed in the temperature range 273-363 K and at total pressures similar to 1 mTorr. The reactions proceed via hydrogen atom transfer leading to HCl product and the corresponding bromomethyl radicals. Their rate constant expressions are (in cm(3) molecule(-1) s(-1)): k(l) = (1.66 +/- 0.14) x 10(-11) exp(-1072 +/- 46/T), k(2) = (0.84 +/- 0.15) x 10(-11) exp(-911 +/- 101/T), and k(3) = (0.43 +/- 0.11) x 10(-11) exp(-809 +/- 142/T). The activation energy of the reaction decreases with additional bromine substitution, which is attributed to the gradual weakening of the corresponding C-H bond strength. Ab initio theoretical calculations performed at the MP2/6-31++G(2d,2p) level of theory suggest C-H bond strengths for CH3Br, CH2Br2, and CHBr3 of 416.58, 407.03, and 396.60 kJ mol(-1), respectively.

  DOI：

  10.1021/jp9719671

文献信息

• FTIR and computational studies of gas-phase hydrogen atom abstraction kinetics by t-butoxy radical
  作者：Shuping Li、Wai Yip Fan

  DOI：10.1016/j.cplett.2006.06.100

  日期：2006.8

  for the hydrogen atom abstraction reactions of several substrates including halogenated organic compounds and amines by t-butoxy radical generated from the uv photolysis of t-butyl nitrite in the gas phase. Arrhenius parameters for selected reactions have been measured in the temperature range 299–318 K. Transition states and activation barriers for such reactions have been computed with the help of

  通过使用傅立叶变换红外（FTIR）吸收光谱法，已确定了包括卤代有机化合物和氢氧烷在内的几种底物的氢原子提取反应的速率系数在10 -16至10 -14  cm 3 分子-1  s -1范围内。通过叔丁氧基自由基在气相中亚硝酸叔丁酯的紫外光解而生成胺。在299–318 K的温度范围内测量了所选反应的Arrhenius参数。借助Gaussian 03软件计算了此类反应的过渡态和激活势垒，发现与实验值非常吻合。
• Halogen abstraction reaction between aminoalkyl radicals and alkyl halides: Unusual high rate constants
  作者：J. Lalevée、X. Allonas、J.P. Fouassier

  DOI：10.1016/j.cplett.2008.02.052

  日期：2008.3

  The very high reactivity of aminoalkyl radicals toward the halogen abstraction reaction is reported for the first time. Reaction rate constants with CCl4 and CBr4 are close to the diffusion limit: they are about 4–5 orders of magnitude higher than those previously determined for typical alkyl radicals. A better understanding of this unusual behavior is obtained using molecular orbitals (MO) calculations

  首次报道了氨基烷基自由基对卤素提取反应的极高反应活性。与CCl 4和CBr 4的反应速率常数接近扩散极限：它们比以前为典型烷基确定的常数高约4-5个数量级。使用分子轨道（MO）计算可以更好地理解这种异常行为。极性效应的参与是直接证据。这种方法对于设计新的还原剂可能很有用。
• Infrared spectral evidence for trihalomethyllithium and -sodium compounds in solid argon
  作者：Lester Andrews、T. Granville Carver

  DOI：10.1021/j100851a061

  日期：1968.5
• Timpe, Hans-Joachim; Wagner, Roland; Paleta, Oldrich, Zeitschrift fur Chemie, 1987, vol. 27, # 11, p. 410 - 411
  作者：Timpe, Hans-Joachim、Wagner, Roland、Paleta, Oldrich

  DOI：——

  日期：——
• The Effect of Halogenation on the C–Br Bond Dissociation Energy in Halogenated Bromomethanes
  作者：M. Szwarc、A. H. Sehon

  DOI：10.1063/1.1748312

  日期：1951.5