3-bromo-6-diazo-9-methyl-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-one | 160510-12-3

• 分子结构分类: 有机化合物 - 有机卤素化合物 - 芳基卤化物
• 英文名称: 3-bromo-6-diazo-9-methyl-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-one
• 英文别名: 3-bromo-6-diazo-9-methyl-8,9-dihydro-7H-benzo[7]annulen-5-one
• CAS: 160510-12-3
• 化学式: C₁₂H₁₁BrN₂O
• 分子量: 279.136
• InChiKey: OZUSGBPTSVBYGY-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3
• 重原子数：
  16
• 可旋转键数：
  0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.33
• 拓扑面积：
  19.1
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  3-bromo-6-diazo-9-methyl-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-one 在 盐酸 、 正丁基锂 、 四丁基氟化铵 、 甲基锂 、 2,3-二氯-5,6-二氰基-1,4-苯醌 作用下， 以 四氢呋喃 、 甲醇 、 苯 为溶剂， 反应 109.25h， 生成 9-isopropyl-2,2,5-trimethylphenaleno<1,9-bc>furan-8(2H)-one
  参考文献：
  名称：

  Total Synthesis of the Phenalenone Diterpene Salvilenone

  摘要：

  The application of a photochemical aromatic annulation strategy in a highly efficient total synthesis of the phenalenone diterpene salvilenone is reported. The pivotal step in the synthesis involves the assembly of the key dihydrophenalene 29 in one step via an annulation involving the siloxyalkyne 28 and either diazo ketone 8 or 9. The synthesis of the alpha-benzosuberone 8 was achieved in three steps beginning with 2-methylcyclopentanone by a route featuring an ''aryne-enolate condensation'' reaction. The alternative aromatic annulation substrate, the beta-benzosuberone 9, was prepared in four steps by a route based on the regiocontrolled ring expansion of the alpha-methylenetetralin 27. The key aromatic annulation was then accomplished by irradiating a mixture of either diazo ketone 8 or 9 and 1.4 equiv of the siloxyalkyne 28 in 1,2-dichloroethane at 20-25 degrees C using a standard Rayonet photochemical reactor. The reaction mixture was next diluted with an equal volume of solvent and heated overnight at 80 degrees C to complete the annulation; concentration and chromatographic purification furnished the tricyclic phenol 29 as colorless crystals in 60-71% yield. Finally, annulation of the furan ring and oxidation required three steps and provided the phenalenone diterpene in good yield. The synthetic routes described herein provide access to salvilenone in only seven or eight steps (via the alpha- and beta-benzosuberone strategies, respectively), half the number of steps required using the classical linear substitution approach reported previously. These highly efficient syntheses demonstrate the ability of the photochemical aromatic annulation strategy to dramatically streamline the synthesis of polycyclic aromatic compounds.

  DOI：

  10.1021/ja00100a009
• 作为产物：
  描述：

  trimethyl-(2-methyl-cyclopent-1-enyloxy)-silane 在 氢氧化钾 、 三氯化铝 、 triisopropylbenzenesulfonyl azide 、 18-冠醚-6 、 四丁基溴化铵 、 溴 、 sodium amide 作用下， 以 苯 为溶剂， 反应 76.0h， 生成 3-bromo-6-diazo-9-methyl-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-one
  参考文献：
  名称：

  Total Synthesis of the Phenalenone Diterpene Salvilenone

  摘要：

  The application of a photochemical aromatic annulation strategy in a highly efficient total synthesis of the phenalenone diterpene salvilenone is reported. The pivotal step in the synthesis involves the assembly of the key dihydrophenalene 29 in one step via an annulation involving the siloxyalkyne 28 and either diazo ketone 8 or 9. The synthesis of the alpha-benzosuberone 8 was achieved in three steps beginning with 2-methylcyclopentanone by a route featuring an ''aryne-enolate condensation'' reaction. The alternative aromatic annulation substrate, the beta-benzosuberone 9, was prepared in four steps by a route based on the regiocontrolled ring expansion of the alpha-methylenetetralin 27. The key aromatic annulation was then accomplished by irradiating a mixture of either diazo ketone 8 or 9 and 1.4 equiv of the siloxyalkyne 28 in 1,2-dichloroethane at 20-25 degrees C using a standard Rayonet photochemical reactor. The reaction mixture was next diluted with an equal volume of solvent and heated overnight at 80 degrees C to complete the annulation; concentration and chromatographic purification furnished the tricyclic phenol 29 as colorless crystals in 60-71% yield. Finally, annulation of the furan ring and oxidation required three steps and provided the phenalenone diterpene in good yield. The synthetic routes described herein provide access to salvilenone in only seven or eight steps (via the alpha- and beta-benzosuberone strategies, respectively), half the number of steps required using the classical linear substitution approach reported previously. These highly efficient syntheses demonstrate the ability of the photochemical aromatic annulation strategy to dramatically streamline the synthesis of polycyclic aromatic compounds.

  DOI：

  10.1021/ja00100a009

文献信息

• Total Synthesis of the Phenalenone Diterpene Salvilenone
  作者：Rick L. Danheiser、Anna L. Helgason

  DOI：10.1021/ja00100a009

  日期：1994.10

  The application of a photochemical aromatic annulation strategy in a highly efficient total synthesis of the phenalenone diterpene salvilenone is reported. The pivotal step in the synthesis involves the assembly of the key dihydrophenalene 29 in one step via an annulation involving the siloxyalkyne 28 and either diazo ketone 8 or 9. The synthesis of the alpha-benzosuberone 8 was achieved in three steps beginning with 2-methylcyclopentanone by a route featuring an ''aryne-enolate condensation'' reaction. The alternative aromatic annulation substrate, the beta-benzosuberone 9, was prepared in four steps by a route based on the regiocontrolled ring expansion of the alpha-methylenetetralin 27. The key aromatic annulation was then accomplished by irradiating a mixture of either diazo ketone 8 or 9 and 1.4 equiv of the siloxyalkyne 28 in 1,2-dichloroethane at 20-25 degrees C using a standard Rayonet photochemical reactor. The reaction mixture was next diluted with an equal volume of solvent and heated overnight at 80 degrees C to complete the annulation; concentration and chromatographic purification furnished the tricyclic phenol 29 as colorless crystals in 60-71% yield. Finally, annulation of the furan ring and oxidation required three steps and provided the phenalenone diterpene in good yield. The synthetic routes described herein provide access to salvilenone in only seven or eight steps (via the alpha- and beta-benzosuberone strategies, respectively), half the number of steps required using the classical linear substitution approach reported previously. These highly efficient syntheses demonstrate the ability of the photochemical aromatic annulation strategy to dramatically streamline the synthesis of polycyclic aromatic compounds.