14-fluoro-3-isopropyliden-2,6,10,15-tetramethyl-20-(trimethylsilyl)eicosa-6(E),10(E),14(Z),18(Z)-tetraen-2-ol | 255845-17-1

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 异戊烯醇脂质
• 英文名称: 14-fluoro-3-isopropyliden-2,6,10,15-tetramethyl-20-(trimethylsilyl)eicosa-6(E),10(E),14(Z),18(Z)-tetraen-2-ol
• 英文别名: (6E,10E,14Z,18Z)-14-fluoro-2,6,10,15-tetramethyl-3-propan-2-ylidene-20-trimethylsilylicosa-6,10,14,18-tetraen-2-ol
• CAS: 255845-17-1
• 化学式: C₃₀H₅₃FOSi
• 分子量: 476.834
• InChiKey: BSVRSVJDPVXGIJ-LWVGTZCGSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  10.24
• 重原子数：
  33
• 可旋转键数：
  15
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.67
• 拓扑面积：
  20.2
• 氢给体数：
  1
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  14-fluoro-3-isopropyliden-2,6,10,15-tetramethyl-20-(trimethylsilyl)eicosa-6(E),10(E),14(Z),18(Z)-tetraen-2-ol 在 三氟乙酸 作用下， 以 二氯甲烷 为溶剂， 反应 0.67h， 以62%的产率得到13-fluoro-3-isopropyliden-22,23,24,25,26,27-hexanodammar-20-ene
  参考文献：
  名称：

  The Fluorine Atom as a Cation-Stabilizing Auxiliary in Biomimetic Polyene Cyclizations:  Total Synthesis of dl-Dammarenediol¹

  摘要：

  Dammarenediols I (1a) and II (1b) were prepared by an efficient nonenzymatic biomimetic polyene tetracyclization route. The cyclization substrate, pentaenol 3, contains a tetramethylallylic alcohol initiator, an allyltrimethylsilane terminating group, and a fluorine atom at pro-C-13 to serve as a cation-stabilizing (C-S) auxiliary controlling the regiochemistry of the C/D ring juncture. The synthesis of 3 employed lithium-halogen exchange to create alcohols 10 and 19. The Z-fluoroalkene in 3 was introduced stereoselectively via the Trost palladium-catalyzed alkylation of allylic acetate 11 (Z/E: 4.6/1). The cyclization of 3 was most efficient (62% isolated yield) when it was added as a dilute solution in dichloromethane to trifluoroacetic acid at -45 degrees C to afford tetracyclic fluoro diene 24 possessing the trans-anti-trans-anti-trans ring stereochemistry of the dammaranes. Replacement of the fluorine atom of 24 with hydrogen with complete retention of configuration was accomplished using the Ohsawa-Oishi reagent (Na/K alloy and crown ether). Wacker oxidation of the resulting hydrocarbon provided ketone 28, which after ketalization was ozonolyzed with a reductive workup to give the SP-alcohol 30. Ketal hydrolysis followed by Grignard reaction with isopentenylmagnesium bromide afforded the dammarenediols (1/3, 1a/1b).

  DOI：

  10.1021/jo991196s
• 作为产物：
  描述：

  2-fluoro-3-methyl-8-(trimethylsilyl)octa-1,6(Z)-dien-3-yl acetate 在 2,6-二甲基吡啶 、 2,2'-联吡啶 、 sodium hydroxide 、 sodium tetrahydroborate 、 potassium tert-butylate 、 叔丁基锂 、 三溴化磷 、 sodium hydride 、 sodium iodide 、 lithium bromide 、 lithium diisopropyl amide 作用下， 以 四氢呋喃 、 甲醇 、 六甲基磷酰三胺 、 乙醚 、 丙酮 为溶剂， 反应 78.58h， 生成 14-fluoro-3-isopropyliden-2,6,10,15-tetramethyl-20-(trimethylsilyl)eicosa-6(E),10(E),14(Z),18(Z)-tetraen-2-ol
  参考文献：
  名称：

  The Fluorine Atom as a Cation-Stabilizing Auxiliary in Biomimetic Polyene Cyclizations:  Total Synthesis of dl-Dammarenediol¹

  摘要：

  Dammarenediols I (1a) and II (1b) were prepared by an efficient nonenzymatic biomimetic polyene tetracyclization route. The cyclization substrate, pentaenol 3, contains a tetramethylallylic alcohol initiator, an allyltrimethylsilane terminating group, and a fluorine atom at pro-C-13 to serve as a cation-stabilizing (C-S) auxiliary controlling the regiochemistry of the C/D ring juncture. The synthesis of 3 employed lithium-halogen exchange to create alcohols 10 and 19. The Z-fluoroalkene in 3 was introduced stereoselectively via the Trost palladium-catalyzed alkylation of allylic acetate 11 (Z/E: 4.6/1). The cyclization of 3 was most efficient (62% isolated yield) when it was added as a dilute solution in dichloromethane to trifluoroacetic acid at -45 degrees C to afford tetracyclic fluoro diene 24 possessing the trans-anti-trans-anti-trans ring stereochemistry of the dammaranes. Replacement of the fluorine atom of 24 with hydrogen with complete retention of configuration was accomplished using the Ohsawa-Oishi reagent (Na/K alloy and crown ether). Wacker oxidation of the resulting hydrocarbon provided ketone 28, which after ketalization was ozonolyzed with a reductive workup to give the SP-alcohol 30. Ketal hydrolysis followed by Grignard reaction with isopentenylmagnesium bromide afforded the dammarenediols (1/3, 1a/1b).

  DOI：

  10.1021/jo991196s

文献信息

• The Fluorine Atom as a Cation-Stabilizing Auxiliary in Biomimetic Polyene Cyclizations:  Total Synthesis of <i>dl</i>-Dammarenediol¹
  作者：William S. Johnson、William R. Bartlett、Boris A. Czeskis、Arnaud Gautier、Cheol H. Lee、Rémy Lemoine、Eric J. Leopold、Gregory R. Luedtke、Katherine J. Bancroft

  DOI：10.1021/jo991196s

  日期：1999.12.1

  Dammarenediols I (1a) and II (1b) were prepared by an efficient nonenzymatic biomimetic polyene tetracyclization route. The cyclization substrate, pentaenol 3, contains a tetramethylallylic alcohol initiator, an allyltrimethylsilane terminating group, and a fluorine atom at pro-C-13 to serve as a cation-stabilizing (C-S) auxiliary controlling the regiochemistry of the C/D ring juncture. The synthesis of 3 employed lithium-halogen exchange to create alcohols 10 and 19. The Z-fluoroalkene in 3 was introduced stereoselectively via the Trost palladium-catalyzed alkylation of allylic acetate 11 (Z/E: 4.6/1). The cyclization of 3 was most efficient (62% isolated yield) when it was added as a dilute solution in dichloromethane to trifluoroacetic acid at -45 degrees C to afford tetracyclic fluoro diene 24 possessing the trans-anti-trans-anti-trans ring stereochemistry of the dammaranes. Replacement of the fluorine atom of 24 with hydrogen with complete retention of configuration was accomplished using the Ohsawa-Oishi reagent (Na/K alloy and crown ether). Wacker oxidation of the resulting hydrocarbon provided ketone 28, which after ketalization was ozonolyzed with a reductive workup to give the SP-alcohol 30. Ketal hydrolysis followed by Grignard reaction with isopentenylmagnesium bromide afforded the dammarenediols (1/3, 1a/1b).