2-Bromo-4-methyl-penta-2,3-dienoic acid ethyl ester

• 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-4-methyl-penta-2,3-dienoic acid ethyl ester
• 化学式: C₈H₁₁BrO₂
• 分子量: 219.078
• InChiKey: ABBJORGCIYCHBH-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.4
• 重原子数：
  11
• 可旋转键数：
  3
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.5
• 拓扑面积：
  26.3
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为产物：
  描述：

  异丁酰氯 、 ethyl 2-bromo-2-(triphenylphosphoranylidene)acetate 在 三乙胺 作用下， 以 二氯甲烷 为溶剂， 以80%的产率得到2-Bromo-4-methyl-penta-2,3-dienoic acid ethyl ester
  参考文献：
  名称：

  Halogenation of keto acid phosphoranes: synthesis of halo enol lactones and haloallenes

  摘要：

  Halolactonization of the keto acid phosphoranes 6a-f, 40, and 41 takes place with either Br2 or SO2Cl2 and Et3N to give the E- and Z-halo enol lactones 10-15, 42, and 43 in good yields. The cyclization proceeds via a halo phosphonium salt, e.g. 19. Halo phosphonium salts yield a halo allene when cyclization is not favoured as in the formation of the bromoallenes 24 and 37. The configuration of the halo enol lactones was determined by H-1 and C-13 NMR spectroscopy and via single-crystal X-ray determinations on 11a, 14c, and 42b. The barrier to interconversion of the biphenyl conformations of the bromo enol lactones 42b and 43b was determined by H-1 NMR spectroscopy at elevated temperatures.

  DOI：

  10.1021/jo00058a039

文献信息

• Abell Andrew D., Hoult Deborah A., Morris Kathy M., Taylor Jane M., Trent+, J. Org. Chem., 58 (1993) N 6, S 1531-1537
  作者：Abell Andrew D., Hoult Deborah A., Morris Kathy M., Taylor Jane M., Trent+

  DOI：——

  日期：——
• Halogenation of keto acid phosphoranes: synthesis of halo enol lactones and haloallenes
  作者：Andrew D. Abell、Deborah A. Hoult、Kathy M. Morris、Jane M. Taylor、John O. Trent

  DOI：10.1021/jo00058a039

  日期：1993.3

  Halolactonization of the keto acid phosphoranes 6a-f, 40, and 41 takes place with either Br2 or SO2Cl2 and Et3N to give the E- and Z-halo enol lactones 10-15, 42, and 43 in good yields. The cyclization proceeds via a halo phosphonium salt, e.g. 19. Halo phosphonium salts yield a halo allene when cyclization is not favoured as in the formation of the bromoallenes 24 and 37. The configuration of the halo enol lactones was determined by H-1 and C-13 NMR spectroscopy and via single-crystal X-ray determinations on 11a, 14c, and 42b. The barrier to interconversion of the biphenyl conformations of the bromo enol lactones 42b and 43b was determined by H-1 NMR spectroscopy at elevated temperatures.