ketene | 107573-87-5

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: ketene
• CAS: 107573-87-5
• 化学式: C₂H₂O
• 分子量: 43.0263
• InChiKey: CCGKOQOJPYTBIH-VQEHIDDOSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  0.8
• 重原子数：
  3
• 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：
  17.1
• 氢给体数：
  0
• 氢受体数：
  1

反应信息

• 作为反应物：
  描述：

  ketene 、 环己烷基甲醛 在 Al(SbF₆)3 作用下， 以 二氯甲烷-D2 为溶剂， 生成
  参考文献：
  名称：

  Lewis酸催化的酰基卤ha醛醛缩合反应的机理

  摘要：

  本文研究了路易斯酸催化的酰基卤-醛-醛环缩合反应的反应机理。铝基催化剂通过乙烯酮依赖性反应途径促进环缩合，而酰基卤烯醇酸酯被认为是Ti（IV）催化反应中的反应性中间体。

  DOI：

  10.1016/s0040-4039(99)01309-x
• 作为产物：
  描述：

  ketene 以 gas 为溶剂， 生成 ketene
  参考文献：
  名称：

  Kinetics of intramolecular carbon atom exchange in ketene

  摘要：

  Intramolecular carbon atom exchange in highly vibrationally excited ketene was studied by monitoring the carbon monoxide fragments (12CO and 13CO ) from the photodissociation of 12CH213CO and 13CH212CO. Two experimental techniques were employed. In one set of experiments the IR transient absorptions of 12CO and 13CO were measured following pulsed excimer excitation of ketene 13C isotopomers, giving carbon atom exchange yields at 351 and 308 nm in a low pressure gas cell. In the other set of experiments, jet-cooled ketene 13C isotopomers were excited with tunable near-UV radiation, and the CO products were detected by monitoring their VUV laser-induced fluorescence. Carbon atom exchange yields were measured for energies extending from below the triplet decomposition threshold (CH2CO→CH2(X 3B1)+CO(X 1Σ+)) to about 4000 cm−1 above the singlet threshold (CH2CO→CH2(a 1A1)+CO(X 1Σ+)). The exchange yields range from 4 to 19%, and the energy dependence of the yield exhibits pronounced structure, with maxima at the triplet and singlet decomposition thresholds. Kinetic measurements of the appearance of the CO products were also performed. The time constant for the appearance of the exchanged CO (e.g., 13CO from 13CH212CO ) is significantly longer than that for the direct CO fragment (e.g., 12CO from 13CH212CO ). All the experimental observations are consistent with a simple reaction mechanism involving ketene isomerization, 13CH212CO⇄12CH213CO, and dissociation, 13CH212CO→13CH2+12CO and 12CH213CO→12CH2+13CO. The isomerization rate constant was determined by analyzing the CO kinetics and the carbon atom exchange yields in terms of the simple isomerization mechanism. A fit of the energy dependence of the isomerization rate constant to the results of tunneling-corrected Rice–Ramsberger–Kassel–Marcus (RRKM) calculations gave the threshold (28360±60 cm−1 ) for the isomerization process.

  DOI：

  10.1063/1.460764

文献信息

• Structures in the energy dependence of the rate constant for ketene isomerization
  作者：Edward R. Lovejoy、C. Bradley Moore

  DOI：10.1063/1.464592

  日期：1993.5.15

  The isomerization of highly vibrationally excited and rotationally cold ketene has been investigated by monitoring the 12CO and 13CO dissociation products following laser excitation of jet-cooled 12CH2 13CO, 13CH2 12CO, and 12CD2 13CO. The rate constants for the reactions 12CH2 13CO⇄13CH2 12CO and 12CD2 13CO⇄13CD2 12CO are reported as a function of energy with a resolution of 1 cm−1. The rate constants exhibit pronounced peaks as a function of energy near the reaction threshold. This structure is attributed to quasistable motion along the reaction coordinate in the vicinity of the isomerization transition state.