4-Ethyl-2,3-dimethyl-2-cyclopentenone | 40515-44-4

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 异戊烯醇脂质
• 英文名称: 4-Ethyl-2,3-dimethyl-2-cyclopentenone
• 英文别名: 4-Ethyl-2,3-dimethylcyclopent-2-en-1-on；4-Ethyl-2,3-dimethylcyclopent-2-en-1-one
• CAS: 40515-44-4
• 化学式: C₉H₁₄O
• 分子量: 138.21
• InChiKey: OVUKXBLWPZQINY-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.7
• 重原子数：
  10
• 可旋转键数：
  1
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.67
• 拓扑面积：
  17.1
• 氢给体数：
  0
• 氢受体数：
  1

反应信息

• 作为产物：
  描述：

  (E,E)-3-Methyl-2,5-octadien-4-one 在 硫酸 作用下， 以37%的产率得到4-Ethyl-2,3-dimethyl-2-cyclopentenone
  参考文献：
  名称：

  Nazarov reaction of trisubstituted dienones: mechanism involving Wagner-Meerwein shift

  摘要：

  The Nazarov reactions of trisubstituted alpha,alpha'-dienones were studied. Whereas alpha,beta-dimethyl-beta'-alkyl alpha,alpha'-dienones gave 2,3-dimethyl-4-alkyl-2-cyclopentenones when heated in concentrated sulfuric acid, the reaction of beta,beta-dimethyl-beta'-alkyl alpha,alpha'-dienones afforded 3,4-dimethyl-4-alkyl-2-cyclopentenones as the rearranged products. A mechanistic investigation using two deuterated dienones suggests that the Nazarov reactions of the latter dienones are accompanied by Wagner-Meerwein shifts to form the most stable carbocations.

  DOI：

  10.1021/jo00002a047

文献信息

• Equilibria Studies on Tetraalkylcyclopentenyl Cations. A Steric Origin for a Baker–Nathan Order?
  作者：K. Ranganayakulu、T. S. Sorensen

  DOI：10.1139/v72-567

  日期：1972.11.1

  The possibilities of using observable cation equilibria to obtain evidence concerning C—H hyperconjugation are discussed. The experimental approach of this paper, using tetraalkylcyclopentenyl cation equilibria, is to vary the structure of the "normal" alkyl series in such a way that the hypothetical C—H hyperconjugative ability remains constant for a given series while the steric bulk of the groups

  讨论了使用可观察的阳离子平衡来获得关于 C-H 超共轭的证据的可能性。本文的实验方法，使用四烷基环戊烯基阳离子平衡，以这样的方式改变“正常”烷基系列的结构，使得假设的 C-H 超共轭能力对于给定系列保持不变，而基团的空间体积发生变化. 事实上，观察到的平衡变化很小。已经进行了其他实验来测量溶剂对平衡常数和平衡反应速率的影响。还设计了其他实验来测试 H 与 CH3 在稳定烷基阳离子方面的能力，并且已经发现 ≥ 4.6 kcal/mol 的值有利于 CH3。最后，
• MOTOYOSHIYA, JIRO;YAZAKI, TOSHIKAZU;HAYASHI, SADAO, J. ORG. CHEM., 56,(1991) N, C. 735-740
  作者：MOTOYOSHIYA, JIRO、YAZAKI, TOSHIKAZU、HAYASHI, SADAO

  DOI：——

  日期：——
• Nazarov reaction of trisubstituted dienones: mechanism involving Wagner-Meerwein shift
  作者：Jiro Motoyoshiya、Toshikazu Yazaki、Sadao Hayashi

  DOI：10.1021/jo00002a047

  日期：1991.1

  The Nazarov reactions of trisubstituted alpha,alpha'-dienones were studied. Whereas alpha,beta-dimethyl-beta'-alkyl alpha,alpha'-dienones gave 2,3-dimethyl-4-alkyl-2-cyclopentenones when heated in concentrated sulfuric acid, the reaction of beta,beta-dimethyl-beta'-alkyl alpha,alpha'-dienones afforded 3,4-dimethyl-4-alkyl-2-cyclopentenones as the rearranged products. A mechanistic investigation using two deuterated dienones suggests that the Nazarov reactions of the latter dienones are accompanied by Wagner-Meerwein shifts to form the most stable carbocations.