methyl 5-bromo-4-(1',1'-dimethylethyl)pentanoate | 142839-54-1

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 脂肪酰基
• 英文名称: methyl 5-bromo-4-(1',1'-dimethylethyl)pentanoate
• 英文别名: Methyl 4-(bromomethyl)-5,5-dimethylhexanoate
• CAS: 142839-54-1
• 化学式: C₁₀H₁₉BrO₂
• 分子量: 251.164
• InChiKey: WYYYMVFVMDHZIK-UHFFFAOYSA-N

物化性质

• 沸点：
  251.0±23.0 °C(Predicted)
• 密度：
  1.192±0.06 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  3.2
• 重原子数：
  13
• 可旋转键数：
  6
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.9
• 拓扑面积：
  26.3
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  methyl 5-bromo-4-(1',1'-dimethylethyl)pentanoate 在 lithium aluminium tetrahydride 作用下， 以 乙醚 为溶剂， 以94%的产率得到5-bromo-4-(1',1'-dimethylethyl)pentanol
  参考文献：
  名称：

  Stereochemistry of the reversible cyclization of .omega.-formylalkyl radicals

  摘要：

  The reactions of 6-bromo-4-(1',1'-dimethylethyl)hexanal (4), 5-bromo-3-(1',1'-dimethylethyl)pentanal (11), and 5-bromo-4-(1',1'-dimethylethyl)pentanal (17) with tributylstannane have been investigated in detail. The major products are the debrominated aldehydes and cycloalkanols which arise from the cyclization of the intermediate omega-formylalkyl radicals. The stersochemical outcome of the cyclization of these radicals is dependent on the stannane concentration. At high concentrations of stannane the cyclization is essentially irreversible with the cycloalkoxy radicals being trapped before beta-scission can occur. Under these conditions the relative amount of cis and trans cycloalkanols formed are equal to the ratio of the rate constants for the two modes of cyclization; both 4 and 17 show a small preference for trans cyclization, but 11 gives equal amounts of the two diastereomers. When the stannane concentration is lowered, the lifetime of the cycloalkoxy radicals increases allowing beta-scission to occur. Thus, the cis and trans cycloalkoxy radicals approach a thermodynamic equilibrium which is reflected in the relative yields of the cis and trans cycloalkanols.

  DOI：

  10.1021/jo00044a034
• 作为产物：
  描述：

  3-Tert-butyl-6-methoxy-6-oxohexanoic acid 在 4-二甲氨基吡啶 、 草酰氯 、 三氯溴甲烷 、 2-mercaptopyridine-1-oxide sodium salt 作用下， 以 四氯化碳 为溶剂， 反应 0.75h， 生成 methyl 5-bromo-4-(1',1'-dimethylethyl)pentanoate
  参考文献：
  名称：

  Stereochemistry of the reversible cyclization of .omega.-formylalkyl radicals

  摘要：

  The reactions of 6-bromo-4-(1',1'-dimethylethyl)hexanal (4), 5-bromo-3-(1',1'-dimethylethyl)pentanal (11), and 5-bromo-4-(1',1'-dimethylethyl)pentanal (17) with tributylstannane have been investigated in detail. The major products are the debrominated aldehydes and cycloalkanols which arise from the cyclization of the intermediate omega-formylalkyl radicals. The stersochemical outcome of the cyclization of these radicals is dependent on the stannane concentration. At high concentrations of stannane the cyclization is essentially irreversible with the cycloalkoxy radicals being trapped before beta-scission can occur. Under these conditions the relative amount of cis and trans cycloalkanols formed are equal to the ratio of the rate constants for the two modes of cyclization; both 4 and 17 show a small preference for trans cyclization, but 11 gives equal amounts of the two diastereomers. When the stannane concentration is lowered, the lifetime of the cycloalkoxy radicals increases allowing beta-scission to occur. Thus, the cis and trans cycloalkoxy radicals approach a thermodynamic equilibrium which is reflected in the relative yields of the cis and trans cycloalkanols.

  DOI：

  10.1021/jo00044a034

文献信息

• Stereochemistry of the reversible cyclization of .omega.-formylalkyl radicals
  作者：A. L. J. Beckwith、K. D. Raner

  DOI：10.1021/jo00044a034

  日期：1992.8

  The reactions of 6-bromo-4-(1',1'-dimethylethyl)hexanal (4), 5-bromo-3-(1',1'-dimethylethyl)pentanal (11), and 5-bromo-4-(1',1'-dimethylethyl)pentanal (17) with tributylstannane have been investigated in detail. The major products are the debrominated aldehydes and cycloalkanols which arise from the cyclization of the intermediate omega-formylalkyl radicals. The stersochemical outcome of the cyclization of these radicals is dependent on the stannane concentration. At high concentrations of stannane the cyclization is essentially irreversible with the cycloalkoxy radicals being trapped before beta-scission can occur. Under these conditions the relative amount of cis and trans cycloalkanols formed are equal to the ratio of the rate constants for the two modes of cyclization; both 4 and 17 show a small preference for trans cyclization, but 11 gives equal amounts of the two diastereomers. When the stannane concentration is lowered, the lifetime of the cycloalkoxy radicals increases allowing beta-scission to occur. Thus, the cis and trans cycloalkoxy radicals approach a thermodynamic equilibrium which is reflected in the relative yields of the cis and trans cycloalkanols.