溴甲基 | 16519-97-4

• 分子结构分类: 有机化合物 - 有机卤素化合物 - 有机溴化物
• 中文名称: 溴甲基
• 英文名称: bromomethyl radical
• CAS: 16519-97-4
• 化学式: CH₂Br
• 分子量: 93.9309
• InChiKey: AOJDZKCUAATBGE-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1
• 重原子数：
  2
• 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：

  溴甲基 在 氢溴酸 作用下， 生成 溴甲烷
  参考文献：
  名称：

  R + HBr ⇄ RH + Br (R = CH2Br、CHBrCl 或 CCl3) 平衡的动力学。CH2Br 和 CHBrCl 自由基的热化学

  摘要：

  CH2Br、CHBrCl 或 CCl3 自由基 R 与 HBr 的反应动力学已在与光电离质谱仪耦合的可加热管式反应器中进行了单独研究。CH2Br（或 CHBrCl 或 CCl3）自由基通过 CH2Br2（或 CHBr2Cl 或 CBrCl3）的脉冲 248 nm 激元激光光解在反应器中均匀地产生。在伪一级条件下监测 R 的衰减作为 HBr 浓度的函数，以确定作为温度函数的速率常数。在很宽的温度范围内分别研究了反应，在这些温度范围内，确定的速率常数符合 Arrhenius 表达式（规定的误差范围为 1σ + 学生 t 值，单位为 cm3 分子−1 s−1）：k( CH2Br + HBr) = (7.5 ± 0.9) × 10−13 exp[−(2.53 ± 0.13) kJ mol−1/RT], k(CHBrCl + HBr) = (4. 9 ± 1.1) × 10−13 exp[−(8.2

  DOI：

  10.1039/b210787m
• 作为产物：
  描述：

  溴碘甲烷 在 Li 作用下， 以 solid matrix 为溶剂， 生成 溴甲基
  参考文献：
  名称：

  Matrix Infrared Spectrum and Bonding in the Monobromomethyl Radical

  摘要：

  The simultaneous deposition of atomic beams of lithium (6Li or 7Li) with CH2BrX (X=F, Cl, Br, I) at high dilution in argon on a CsI cold window at 15°K produces infrared absorptions identified as the monobromomethyl radical and the corresponding lithium halide. The identity of the radical is confirmed by comparing the spectra of the reactions of CH2BrX (X=Br, I) with Na and K. The reactions of CHDBr2 and CD2Br2 with Li and Na support assignments to v2, the symmetric H–C–H valence angle bend, v3, the C–Br stretch, and v6, the out-of-plane hydrogen bend, of the monobromomethyl radical. Bromine isotopic splittings are observed for the first time in an argon matrix. The high C–Br stretching force constant (3.42 ± 0.02 mdyn/ Å) indicates considerable electronic stabilization in the CH2Br radical and suggests (p–p) π and some (p–d) π bonding between carbon and bromine. The large positive quartic term in the out-of-plane bending potential function is consistent with a planar radical.

  DOI：

  10.1063/1.1675671

文献信息

• 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。
• Adiabatic and diabatic dynamics in the photodissociation of CH2BrCl
  作者：Peng Zou、W. Sean McGivern、Simon W. North

  DOI：10.1039/b004349o

  日期：——

  The photodissociation dynamics of chlorobromomethane (CBM) were investigated between 193 and 242 nm by resonance-enhanced multiphoton ionization (REMPI) with time-of-flight mass spectrometry (TOFMS). Translational energy distributions, anisotropy parameters, and Br:Br* branching ratios were determined at 193 and 235 nm to explore the non-adiabatic dynamics near the avoided crossing. Additional measurements

  通过共振增强多光子电离 (REMPI) 和飞行时间质谱 (TOFMS) 在 193 和 242 nm 之间研究氯溴甲烷 (CBM) 的光解动力学。在 193 和 235 nm 处测定平移能量分布、各向异性参数和 Br:Br* 支化比，以探索避免交叉附近的非绝热动力学。在中间波长进行了额外的测量，以表征 Br 和 Br* 各向异性参数的波长依赖性。通过应用一维 Landau-Zener 模型计算的非绝热交叉概率对激发波长相对不敏感，表明 3A' 和 4A' 电位之间的避免交叉位于出口通道中。此外，
• Femtosecond photolysis of CH2Br2 in acetonitrile: Capturing the bromomethyl radical and bromine-atom charge transfer complex through deep-to-near UV probing
  作者：Suman K. Pal、Andrey S. Mereshchenko、Patrick Z. El-Khoury、Alexander N. Tarnovsky

  DOI：10.1016/j.cplett.2011.02.046

  日期：2011.4

  radical and solvent Br charge-transfer complexes. Following irradiation of CH2Br2 at 255 nm, the iso-H2CBrBr isomer product rapidly converts back to the parent species, and transient absorption spectra reveal the bands of solvent-separated radical species, the CH2Br radical peaking at 235 nm, as well as the CH3CN·Br complex at 272 nm. The absorption of CH2Br exhibits minor solvatochromic shifts upon going

  乙腈中的二溴甲烷（CH 2 Br 2）是表征CH 2 Br吸收特征的合适前体 自由基和溶剂 Br电荷转移络合物。在255 nm处辐射CH 2 Br 2之后，异-H 2 CBrBr异构体产物迅速转化回母体，瞬态吸收光谱揭示了溶剂分离的自由基物质CH 2 Br的谱带。自由基在235 nm处达到峰值，以及CH 3 CN·Br络合物在272 nm处达到峰值。CH 2 Br的吸收从乙腈到环己烷时，溶剂溶变色变小，CH 3 CN·Br的分子十年代消光系数估计为1470 M -1  cm -1。
• First observation of the rotational spectrum of the bromomethyl radical, CH₂Br
  作者：Stéphane Bailleux、Pascal Dréan、Marc Godon、Zdeněk Zelinger、Chuanxi Duan

  DOI：10.1039/b405115g

  日期：——

  rotational spectrum of the bromomethyl radical in the gas phase has been observed. The radical was produced in a fast flow system by hydrogen abstraction of CH3Br by Cl or F atoms obtained from a 2450 MHz microwave discharge in Cl2 or in CF4, respectively. The rotational, quartic centrifugal distortion constants have been obtained as well as the electron spin–rotation interaction constants. The small

  已经观察到气相中溴甲基自由基的第一个高分辨率旋转光谱。自由基是在快速流动系统中通过分别在 Cl2 或 CF4 中通过 2450 MHz 微波放电获得的 Cl 或 F 原子对 CH3Br 进行氢提取而产生的。已经获得了旋转的四次离心畸变常数以及电子自旋-旋转相互作用常数。从 CH279Br 物种的旋转常数推导出的小的正惯性缺陷 Δ0 = 0.032 amu A2 清楚地表明自由基在其基态振动状态下是平面的。
• Kinetics of reactions of halogenated methyl radicals with hydrogen iodide
  作者：Jorma A. Seetula、David Gutman

  DOI：10.1021/j100162a036

  日期：1991.5

  The kinetics of the reactions of CH2I, CH2Br, CH2Cl, and CHCl2 with HI were studied in a tubular reactor coupled to a photoionization mass spectrometer. Rate constants were measured as a function of temperature (typically between 294 and 552 K) to determine Arrhenius parameters. For these and other R + HI reactions studied to date (i.e., those involving alkyl radicals), a linear free energy relationship was discovered which correlates the large differences in reactivity among all these R + HI reactions with the inductive effect of the substituent atoms or groups on the central carbon atom.