3-Methyl-3-carbomethoxy-5(E)-<(17β-acetoxyandrosta-3,5-dien-3-yl)methylidene>tetrahydrofuran-2-one | 137742-32-6

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 类固醇和类固醇衍生物
• 英文名称: 3-Methyl-3-carbomethoxy-5(E)-<(17β-acetoxyandrosta-3,5-dien-3-yl)methylidene>tetrahydrofuran-2-one
• CAS: 137742-32-6；137820-54-3
• 化学式: C₂₉H₃₈O₆
• 分子量: 482.617
• InChiKey: WNPVAJKOLWXUCK-KLXZDYISSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5.43
• 重原子数：
  35.0
• 可旋转键数：
  3.0
• 环数：
  5.0
• sp3杂化的碳原子比例：
  0.69
• 拓扑面积：
  78.9
• 氢给体数：
  0.0
• 氢受体数：
  6.0

反应信息

• 作为产物：
  描述：

  17β-acetoxy-androst-3,5-dien-3-yl triflate 、 2-methyl-2-(2-propynyl)malonic acid monomethyl ester 在 二乙酰二(三苯基膦)钯 四丁基氯化铵 、 三乙胺 作用下， 以 乙腈 为溶剂， 反应 0.33h， 以68%的产率得到3-Methyl-3-carbomethoxy-5(E)-<(17β-acetoxyandrosta-3,5-dien-3-yl)methylidene>tetrahydrofuran-2-one
  参考文献：
  名称：

  Palladium-catalyzed reaction of vinyl triflates and vinyl/aryl halides with 4-alkynoic acids: regio- and stereoselective synthesis of (E)-.delta.-vinyl/aryl-.gamma.-methylene-.gamma.-butyrolactones

  摘要：

  The palladium-catalyzed reaction of vinyl triflates and vinyl/aryl halides with 4-pentynoic acid, 2,2-disubstituted 4-pentynoic acids, and 5-substituted 4-pentynoic acids produced regio- and stereoselectively the corresponding (E)-delta-vinyl/aryl-gamma-methylene-gamma-butyrolactones in good to high yield. Reactions were carried out in the presence of catalytic amounts of Pd(OAc)2(PPh3)2 or Pd(PPh3)4, Et3N, and n-Bu4NCl. The presence of chloride anions was found to be necessary to obtain the best results. The proposed mechanism involves an intramolecular nucleophilic attack of the carboxylate anion on the palladium-coordinated carbon-carbon triple bond and subsequent reductive elimination of Pd(0) species from the resulting sigma-vinylpalladium complex which regenerates the catalyst and releases the exocyclic enol lactone.

  DOI：

  10.1021/jo00029a035