2-methyl-4,5-dehydro ε-lactone | 1092695-33-4

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 内酯类
• 英文名称: 2-methyl-4,5-dehydro ε-lactone
• 英文别名: 6-methyl-5,6-dihydro-2H-oxepin-7-one
• CAS: 1092695-33-4
• 化学式: C₇H₁₀O₂
• 分子量: 126.155
• InChiKey: UVRZOCNFIGMERF-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.3
• 重原子数：
  9
• 可旋转键数：
  0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.57
• 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-methyl-4,5-dehydro ε-lactone 在 aluminum tris(2,6-diphenylphenoxide) 、 RuCl2(1,3-dimesityl-imidazolidin-2-yl)(PCy3)(=CHPh) 作用下， 以 二氯甲烷 为溶剂， 生成 5-Ethenyl-3-methyloxolan-2-one
  参考文献：
  名称：

  Substrate Encapsulation: An Efficient Strategy for the RCM Synthesis of Unsaturated ϵ-Lactones

  摘要：

  A facile substrate-encapsulated RCM-based synthesis of 7-membered lactones is reported. Coordination of the alpha,omega-dienyl ester precursor to the bulky Lewis acid (LA) aluminum tris(2,6-diphenylphenoxide) (ATPH) provides a protective extended steric pocket to the olefin moieties, thereby favoring intramolecular RCM over intermolecular ADMET oligomerization. The LA-encapsulated esters undergo ring-closure in the presence of Ru-based olefin metathesis catalysts to give previously difficult-to-access 7-membered beta,gamma- and gamma,delta-unsaturated lactones in good yields.

  DOI：

  10.1021/ol8022227
• 作为产物：
  描述：

  allyl 2-methyl-4-pentenoate 在 aluminum tris(2,6-diphenylphenoxide) 、 Hoveyda-Grubbs catalyst second generation 作用下， 以 二氯甲烷 为溶剂， 反应 8.25h， 以80%的产率得到2-methyl-4,5-dehydro ε-lactone
  参考文献：
  名称：

  Substrate Encapsulation: An Efficient Strategy for the RCM Synthesis of Unsaturated ϵ-Lactones

  摘要：

  A facile substrate-encapsulated RCM-based synthesis of 7-membered lactones is reported. Coordination of the alpha,omega-dienyl ester precursor to the bulky Lewis acid (LA) aluminum tris(2,6-diphenylphenoxide) (ATPH) provides a protective extended steric pocket to the olefin moieties, thereby favoring intramolecular RCM over intermolecular ADMET oligomerization. The LA-encapsulated esters undergo ring-closure in the presence of Ru-based olefin metathesis catalysts to give previously difficult-to-access 7-membered beta,gamma- and gamma,delta-unsaturated lactones in good yields.

  DOI：

  10.1021/ol8022227

文献信息

• Substrate Encapsulation: An Efficient Strategy for the RCM Synthesis of Unsaturated ϵ-Lactones
  作者：Emily B. Pentzer、Tendai Gadzikwa、SonBinh T. Nguyen

  DOI：10.1021/ol8022227

  日期：2008.12.18

  A facile substrate-encapsulated RCM-based synthesis of 7-membered lactones is reported. Coordination of the alpha,omega-dienyl ester precursor to the bulky Lewis acid (LA) aluminum tris(2,6-diphenylphenoxide) (ATPH) provides a protective extended steric pocket to the olefin moieties, thereby favoring intramolecular RCM over intermolecular ADMET oligomerization. The LA-encapsulated esters undergo ring-closure in the presence of Ru-based olefin metathesis catalysts to give previously difficult-to-access 7-membered beta,gamma- and gamma,delta-unsaturated lactones in good yields.