(2-ethoxy-1-methylcyclopent-2-en-1-yl)methanol | 138260-36-3

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: (2-ethoxy-1-methylcyclopent-2-en-1-yl)methanol
• CAS: 138260-36-3
• 化学式: C₉H₁₆O₂
• 分子量: 156.225
• InChiKey: VUKGKKKJHIFNGE-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.7
• 重原子数：
  11.0
• 可旋转键数：
  3.0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.78
• 拓扑面积：
  29.46
• 氢给体数：
  1.0
• 氢受体数：
  2.0

反应信息

• 作为反应物：
  描述：

  (2-ethoxy-1-methylcyclopent-2-en-1-yl)methanol 在 吡啶 、 硫酸 作用下， 以 二氯甲烷 为溶剂， 反应 0.67h， 生成 (1-Methyl-2-oxocyclopentyl)methyl 2,5-Dibromopentanoate
  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
• 作为产物：
  描述：

  2-甲氧羰基环戊酮 在 lithium aluminium tetrahydride 、 对甲苯磺酸 作用下， 以 乙醚 为溶剂， 生成 (2-ethoxy-1-methylcyclopent-2-en-1-yl)methanol
  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

文献信息

• Daphniphyllum Alkaloids. 16. Total Synthesis of (+)-Codaphniphylline
  作者：Clayton H. Heathcock、John C. Kath、Roger B. Ruggeri

  DOI：10.1021/jo00110a013

  日期：1995.3

  A total synthesis of (+)-codaphniphylline (3) has been developed. The synthesis begins with Noyori asymmetric reduction of methyl 2-oxocyclopentanecarboxylate (15), which gives the trans-P-hydroxy ester 16 (93% ee). Frater-Seebach alkylation of this material with homogeranyl iodide gives hydroxy esters 18 and 19 in a ratio of 15:1. This mixture is oxidized to keto ester 29, which is converted into acetal 34. Reduction of the ester function gives primary alcohol 35, which is esterified by treatment with 2-bromo-4-chlorobutanoyl chloride. The resulting keto ester, 33, is treated with unactivated zinc dust in the presence of 2 equiv of ZnCl2 to obtain lactone ether 36, which is reduced by lithium aluminum hydride to diol 9. Serial treatment of this material with Swern oxidant, methylamine, and warm acetic acid provides the hexacyclic amino ether 10 in 63% overall yield. Reductive fragmentation to 11 results when 10 is treated with excess diisobutylaluminum hydride in hot toluene. Ring closure to the daphnane skeleton (12) occurs when the N,O-bis(phenylcarbamoyl) derivative 41 is treated with hot acetic acid, followed by KOH in methanol. Displacement of the tosyl group gives sulfide 50, which is oxidized to sulfone 13. This material is metalated and coupled with enantiomerically-pure aldehyde 46 to secure the codaphniphylline skeleton, as a mixture of four diastereomeric beta-hydroxy sulfones (51). Oxidation gives a mixture of diastereomeric beta-keto sulfones (52), which is desulfonated to obtain (+)-codaphniphylline (3). The synthesis requires 12 steps from homogeranyl iodide, the more precious starting material, and provides the enantiomerically pure alkaloid in 9% overall yield.