7a-(2-Methyl-2-propenyl)-octahydro-5H,7H-cyclopentapyrano<2,3-d>pyran-5-one | 138332-64-6

• 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: 7a-(2-Methyl-2-propenyl)-octahydro-5H,7H-cyclopentapyrano<2,3-d>pyran-5-one
• CAS: 138332-64-6
• 化学式: C₁₅H₂₂O₃
• 分子量: 250.338
• InChiKey: KMLSMOBQRVCULZ-CFVMTHIKSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.85
• 重原子数：
  18.0
• 可旋转键数：
  2.0
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.8
• 拓扑面积：
  35.53
• 氢给体数：
  0.0
• 氢受体数：
  3.0

反应信息

• 作为产物：
  描述：

  2-Ethoxy-1-(2-methyl-2-propenyl)-2-cyclopentene-1-methanol 在 吡啶 、 六甲基磷酰三胺 、 硫酸 、 sodium naphthalenide 、 zinc(II) chloride 作用下， 以 二氯甲烷 为溶剂， 反应 9.67h， 生成 7a-(2-Methyl-2-propenyl)-octahydro-5H,7H-cyclopentapyrano<2,3-d>pyran-5-one
  参考文献：
  名称：

  Daphniphyllum alkaloids. 15. Total syntheses of (.+-.)-methyl homodaphniphyllate and (.+-.)-daphnilactone A

  摘要：

  Biomimetic total syntheses of (+/-)-daphnilactone A (6) and (+/-)-methyl homodaphniphyllate (4) have been carried out. The syntheses began with the preparation of tricyclic lactone ether 18d, which was reduced to diol 19d with LiAlH4. Oxidation of 19d gave a sensitive dialdehyde (20d), which was treated sequentially with ammonia and warm acetic acid to obtain the hexacyclic amino ether 22d. The tetracyclization process leading from 19d to 22d proceeded in 47% yield and resulted in the formation of five new sigma-bonds and four new rings. After hydrogenation of the double bond, the saturated amino ether 7 was fragmented by treatment with diisobutylaluminum hydride in refluxing toluene. Unsaturated amino alcohol 23 was obtained in 71% yield, accompanied by a smaller amount of the simple elimination product 24. Compound 23 was converted into (+/-)-daphnilactone A (6) by oxidation to the unsaturated amino acid, which was cyclized by treatment with aqueous formaldehyde at pH 7. For the preparation of 4, compound 23 was oxidized and the resulting amino acid esterified to obtain 26. Treatment of this compound with phenyl isocyanate gave a urea derivative (27) that underwent smooth cyclization to (+/-)-methyl homodaphniphyllate (4) in refluxing formic acid. From homogeranyl iodide, the limiting starting material, compound 6 was obtained in 11 steps and 8% overall yield and compound 4 was obtained in 13 steps and 11% overall yield.

  DOI：

  10.1021/jo00035a012