1-((E)-1,4-Dimethyl-3-phenyl-penta-1,4-dienyl)-4-methyl-benzene | 131122-92-4

• 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: 1-((E)-1,4-Dimethyl-3-phenyl-penta-1,4-dienyl)-4-methyl-benzene
• 英文别名: 1-methyl-4-[(2E)-5-methyl-4-phenylhexa-2,5-dien-2-yl]benzene
• CAS: 131122-92-4
• 化学式: C₂₀H₂₂
• 分子量: 262.395
• InChiKey: LCBGCQILIULLBN-SAPNQHFASA-N

计算性质

• 辛醇/水分配系数(LogP)：
  6.7
• 重原子数：
  20
• 可旋转键数：
  4
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.2
• 拓扑面积：
  0
• 氢给体数：
  0
• 氢受体数：
  0

反应信息

• 作为产物：
  描述：

  1-[1-[(1S,3R)-2,2-dimethyl-3-phenylcyclopropyl]ethenyl]-4-methylbenzene 生成 1-((E)-1,4-Dimethyl-3-phenyl-penta-1,4-dienyl)-4-methyl-benzene
  参考文献：
  名称：

  PEGG, GRAHAM G.;MEEHAN, GEORGE V., AUSTRAL. J. CHEM., 43,(1990) N, C. 1357-1365

  摘要：

  DOI：

文献信息

• Substituent Rate Effects in Sigmatropic Homodienyl [1,5]-Hydrogen Migrations
  作者：GG Pegg、GV Meehan

  DOI：10.1071/ch9901357

  日期：——

  The small but systematic polar substituent effect on the rates of [1,5]- homodienyl hydrogen migrations previously observed for the series of alkenylcyclopropane substrates (1) has been further explored through two additional substrate series (4) and (6) bearing the aryl probe at C4 and at the migration origin C1 respectively. However, negligible substituent effects were apparent at these positions. It now seems that the substituent effect originally observed at C5 reflects electronic perturbation by the substituent, rather than an inherent charge separation in the transition state for homodienyl rearrangement. The aryl group at C1 of the series (6) does, however, afford a substantial rate enhancement relative to the parent cis-1-methyl-2-vinylcyclopropane. In addition, exclusive formation of (1E,4Z)-1-arylhexa-1,4-diene rearrangement products is observed. These kinetic and stereochemical observations are interpreted in terms of a stereoelectronically favoured equatorial conformation for the aryl group in the transition state for rearrangement.

  之前在烯基环丙烷底物系列 (1) 中观察到极性取代基对 [1,5]- 同二烯基氢迁移速率的影响很小，但这种影响是系统性的，我们通过另外两个底物系列 (4) 和 (6) 进行了进一步探索，这两个底物系列分别在 C4 和迁移原点 C1 上带有芳基探针。然而，这些位置上的取代基效应微乎其微。现在看来，最初在 C5 处观察到的取代基效应反映的是取代基的电子扰动，而不是同二烯基重排过渡态中固有的电荷分离。不过，与母体顺式-1-甲基-2-乙烯基环丙烷相比，系列 (6) 中 C1 处的芳基确实能大幅提高速率。此外，还观察到 (1E,4Z)-1-芳基己-1,4-二烯重排产物的独家形成。这些动力学和立体化学观察结果可以用芳基在重排过渡态中的立体电子学有利赤道构象来解释。