1-(5-bromo-n-pentyl)-1-methyl-2-methylenecyclohexane | 144241-77-0

• 分子结构分类: 有机化合物 - 有机卤素化合物 - 有机溴化物
• 英文名称: 1-(5-bromo-n-pentyl)-1-methyl-2-methylenecyclohexane
• 英文别名: 1-(5-Bromopentyl)-1-methyl-2-methylidenecyclohexane
• CAS: 144241-77-0
• 化学式: C₁₃H₂₃Br
• 分子量: 259.23
• InChiKey: ADIIANPEADDJFX-UHFFFAOYSA-N

物化性质

• 沸点：
  288.4±9.0 °C(Predicted)
• 密度：
  1.11±0.1 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  5.5
• 重原子数：
  14
• 可旋转键数：
  5
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.85
• 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：

  1,2-二甲撑环己烷 在 oxonium 、 magnesium 作用下， 以 四氢呋喃 为溶剂， 反应 7.5h， 生成 1-(5-bromo-n-pentyl)-1-methyl-2-methylenecyclohexane
  参考文献：
  名称：

  One-step spiroannulation using 1,2-bis(methylene)cycloalkane-magnesium reagents

  摘要：

  A one-step method for the synthesis of a wide variety of spirocyclic systems has been developed based on the reactions of bis-electrophiles with a series of new 1,3-diene-magnesium reagents, the magnesium complexes of 1,2-bis(methylene)cycloalkanes. The direct metalation of 1,2-bis(methylene)cycloalkanes with highly reactive magnesium in THF at ambient temperature generates the corresponding diene-magnesium reagents in high yields. Reactions of the diene-magnesium reagents with 1,n-dibromoalkanes produce a large number of spirocarbocycles containing an exocyclic double bond. The ring sizes of the accessible spiro compounds can be any combinations of four- to seven-membered rings. In most cases, the initially alkylated intermediates can be trapped by protonation, giving the corresponding bromo olefins. Significantly, treatment of the diene-magnesium reagents with bromoalkyl nitriles leads to a one-step synthesis of keto-functionalized spirocycles. The initial adduct is believed to be a Grignard reagent containing a cyano group. When a bromo nitrile containing a cyclic moiety is used as the bis-electrophile, the approach provides a direct access to dispiroenones.

  DOI：

  10.1021/jo00050a036

文献信息

• One-step spiroannulation using 1,2-bis(methylene)cycloalkane-magnesium reagents
  作者：Reuben D. Rieke、Heping Xiong

  DOI：10.1021/jo00050a036

  日期：1992.11

  A one-step method for the synthesis of a wide variety of spirocyclic systems has been developed based on the reactions of bis-electrophiles with a series of new 1,3-diene-magnesium reagents, the magnesium complexes of 1,2-bis(methylene)cycloalkanes. The direct metalation of 1,2-bis(methylene)cycloalkanes with highly reactive magnesium in THF at ambient temperature generates the corresponding diene-magnesium reagents in high yields. Reactions of the diene-magnesium reagents with 1,n-dibromoalkanes produce a large number of spirocarbocycles containing an exocyclic double bond. The ring sizes of the accessible spiro compounds can be any combinations of four- to seven-membered rings. In most cases, the initially alkylated intermediates can be trapped by protonation, giving the corresponding bromo olefins. Significantly, treatment of the diene-magnesium reagents with bromoalkyl nitriles leads to a one-step synthesis of keto-functionalized spirocycles. The initial adduct is believed to be a Grignard reagent containing a cyano group. When a bromo nitrile containing a cyclic moiety is used as the bis-electrophile, the approach provides a direct access to dispiroenones.