[2-bromo-1-[(E)-prop-1-enyl]cyclohex-2-en-1-yl] butanoate | 423764-49-2

• 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: [2-bromo-1-[(E)-prop-1-enyl]cyclohex-2-en-1-yl] butanoate
• CAS: 423764-49-2
• 化学式: C₁₃H₁₉BrO₂
• 分子量: 287.197
• InChiKey: QCINOQUMIYMSTI-RUDMXATFSA-N

物化性质

• 沸点：
  313.6±42.0 °C(Predicted)
• 密度：
  1.25±0.1 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  3.7
• 重原子数：
  16
• 可旋转键数：
  5
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.62
• 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：

  [2-bromo-1-[(E)-prop-1-enyl]cyclohex-2-en-1-yl] butanoate 在 四丁基氟化铵 、 双(三甲基硅烷基)氨基钾 作用下， 以 四氢呋喃 、 乙醚 为溶剂， 生成 (2S,3S,4E)-4-(2-bromocyclohex-2-en-1-ylidene)-2-ethyl-3-methylbutanoic acid
  参考文献：
  名称：

  Intramolecularly Competitive Ireland-Claisen Rearrangements:  Scope and Potential Applications to Natural Product Synthesis

  摘要：

  A variety of bis-allylic esters were prepared by vinylmetal addition to cycloalkenones followed by esterification either in situ or in a separate operation. For chiral cyclohexenones, the vinyl additions generally occurred with > 10:1 diastereoselectivity. Although in some cases the bis-allylic esters proved to be sensitive to silica gel or other adsorbents, all of the esters examined could be isolated in acceptable purity. The Ireland-Claisen rearrangement of the bis-allylic esters occurred with complete regioselectivity via the exocyclic alkene. The alkene stereochemistry and the stereochemistry at C-2 and C-3 of the pentenoic acid products were consistent with a chairlike transition state in the rearrangement. Substituents at the carbons adjacent to the allylic carbinol carbon (i.e., C-2 or C-6 in cyclohexenone-derived substrates) directed the stereochemical course of the rearrangement. The rearrangements generally proceeded so as to place the larger of the C-2 or C-6 substituents in the pseudoequatorial position with respect to the chairlike transition state. For a bis-allylic ester bearing both a C-2-CH3 and a C-6-OMEM substituent, the rearrangement product resulted from the nominally smaller OMEM substituent occupying a pseudoequatorial position with respect to the chairlike transition state.

  DOI：

  10.1021/jo010752r
• 作为产物：
  描述：

  反-1-溴-1-丙烯 、 2-溴-2-环己烯-1-酮 、 丁酰氯 在 叔丁基锂 作用下， 以 四氢呋喃 、 正戊烷 为溶剂， 反应 0.25h， 生成 [2-bromo-1-[(E)-prop-1-enyl]cyclohex-2-en-1-yl] butanoate
  参考文献：
  名称：

  Intramolecularly Competitive Ireland-Claisen Rearrangements:  Scope and Potential Applications to Natural Product Synthesis

  摘要：

  A variety of bis-allylic esters were prepared by vinylmetal addition to cycloalkenones followed by esterification either in situ or in a separate operation. For chiral cyclohexenones, the vinyl additions generally occurred with > 10:1 diastereoselectivity. Although in some cases the bis-allylic esters proved to be sensitive to silica gel or other adsorbents, all of the esters examined could be isolated in acceptable purity. The Ireland-Claisen rearrangement of the bis-allylic esters occurred with complete regioselectivity via the exocyclic alkene. The alkene stereochemistry and the stereochemistry at C-2 and C-3 of the pentenoic acid products were consistent with a chairlike transition state in the rearrangement. Substituents at the carbons adjacent to the allylic carbinol carbon (i.e., C-2 or C-6 in cyclohexenone-derived substrates) directed the stereochemical course of the rearrangement. The rearrangements generally proceeded so as to place the larger of the C-2 or C-6 substituents in the pseudoequatorial position with respect to the chairlike transition state. For a bis-allylic ester bearing both a C-2-CH3 and a C-6-OMEM substituent, the rearrangement product resulted from the nominally smaller OMEM substituent occupying a pseudoequatorial position with respect to the chairlike transition state.

  DOI：

  10.1021/jo010752r

文献信息

• A simple 13 C NMR method for determination of the relative stereochemistry of 2,3-dialkylpentenoic acids and related compounds
  作者：Sang-phyo Hong、Matthias C McIntosh

  DOI：10.1016/s0040-4020(01)00349-0

  日期：2001.6

  The relative stereochemistry of 2,3-dialkylpentenoic acids and derivatives thereof can be easily determined by comparison of 13C NMR spectra of the syn and anti isomers. The chemical shifts of several of the resonances of the anti isomer lie downfield relative to the syn isomer.

  通过比较顺式和反式异构体的13 C NMR光谱，可以轻松确定2，3-二烷基戊烯酸及其衍生物的相对立体化学。相对于顺式异构体，反式异构体的几个共振的化学位移位于低场。