(E)-2-(p-bromophenyl)-3-p-tolylcyclopropanecarboxylic acid | 32092-95-8

• 分子结构分类: 有机化合物 - 苯丙烷和聚酮 - 二苯乙烯类
• 英文名称: (E)-2-(p-bromophenyl)-3-p-tolylcyclopropanecarboxylic acid
• 英文别名: (2S,3S)-2-(4-bromophenyl)-3-(4-methylphenyl)cyclopropane-1-carboxylic acid
• CAS: 32092-95-8；144017-22-1
• 化学式: C₁₇H₁₅BrO₂
• 分子量: 331.209
• InChiKey: ZXZRAWFBIWKCBC-KSCSMHSMSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.1
• 重原子数：
  20
• 可旋转键数：
  3
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.24
• 拓扑面积：
  37.3
• 氢给体数：
  1
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  (E)-2-(p-bromophenyl)-3-p-tolylcyclopropanecarboxylic acid 在 叠氮磷酸二苯酯 、 乙酸酐 、 溶剂黄146 、 三乙胺 、 sodium nitrite 作用下， 反应 10.0h， 生成 ethyl N-nitroso-N-<(E)-2-(p-bromophenyl)-3-p-tolylcyclopropyl>carbamate
  参考文献：
  名称：

  Electron demand in the transition state of the cyclopropylidene to allene ring opening

  摘要：

  The electronic structure of the transition state for the cyclopropylidene to allene conversion has been probed. The methodology involved the relative rates of ring opening vs trapping by MeOH for a series of variously substituted 2,3-diarylcyclopropylidenes. With the assumption that the rate of trapping was unaffected by substituents, a Hammett correlation was constructed. The negative value (-0.72) for rho indicated that the carbenic center attracts electron density in the ring-opening transition state, much like the cyclopropyl cation to allyl cation transition state. Temperature-dependent studies showed that the observed preference for ring opening was driven by entropy factors. Also, using reasonable estimates for the close to diffusion-controlled trapping activation enthalpies, the derived enthalpies for ring opening were in close agreement with the best theoretical values.

  DOI：

  10.1021/jo00049a042
• 作为产物：
  描述：

  4-甲基苯三苯基氯化磷 在 sodium hydroxide 、 potassium tert-butylate 、 碘 、 copper(II) sulfate 作用下， 以 甲醇 、 苯 为溶剂， 反应 1.5h， 生成 (E)-2-(p-bromophenyl)-3-p-tolylcyclopropanecarboxylic acid
  参考文献：
  名称：

  Electron demand in the transition state of the cyclopropylidene to allene ring opening

  摘要：

  The electronic structure of the transition state for the cyclopropylidene to allene conversion has been probed. The methodology involved the relative rates of ring opening vs trapping by MeOH for a series of variously substituted 2,3-diarylcyclopropylidenes. With the assumption that the rate of trapping was unaffected by substituents, a Hammett correlation was constructed. The negative value (-0.72) for rho indicated that the carbenic center attracts electron density in the ring-opening transition state, much like the cyclopropyl cation to allyl cation transition state. Temperature-dependent studies showed that the observed preference for ring opening was driven by entropy factors. Also, using reasonable estimates for the close to diffusion-controlled trapping activation enthalpies, the derived enthalpies for ring opening were in close agreement with the best theoretical values.

  DOI：

  10.1021/jo00049a042

文献信息

• Electron demand in the transition state of the cyclopropylidene to allene ring opening
  作者：Philip Warner、Robert Sutherland

  DOI：10.1021/jo00049a042

  日期：1992.11

  The electronic structure of the transition state for the cyclopropylidene to allene conversion has been probed. The methodology involved the relative rates of ring opening vs trapping by MeOH for a series of variously substituted 2,3-diarylcyclopropylidenes. With the assumption that the rate of trapping was unaffected by substituents, a Hammett correlation was constructed. The negative value (-0.72) for rho indicated that the carbenic center attracts electron density in the ring-opening transition state, much like the cyclopropyl cation to allyl cation transition state. Temperature-dependent studies showed that the observed preference for ring opening was driven by entropy factors. Also, using reasonable estimates for the close to diffusion-controlled trapping activation enthalpies, the derived enthalpies for ring opening were in close agreement with the best theoretical values.