tetramethyl 1,5-dimethyltetracyclo[3.3.0^1,5.0^2,8.0^4,6]octane-3-exo,7-exo-dibromo-2,4,6,8-tetracarboxylate | 206660-59-5

• 分子结构分类: 有机化合物 - 有机酸及其衍生物 - 羧酸及其衍生物
• 英文名称: tetramethyl 1,5-dimethyltetracyclo[3.3.0^1,5.0^2,8.0^4,6]octane-3-exo,7-exo-dibromo-2,4,6,8-tetracarboxylate
• CAS: 206660-59-5
• 化学式: C₁₈H₂₀Br₂O₈
• 分子量: 524.16
• InChiKey: LFKGWTQJNZHRLJ-HBRBALROSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.22
• 重原子数：
  28.0
• 可旋转键数：
  4.0
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.78
• 拓扑面积：
  105.2
• 氢给体数：
  0.0
• 氢受体数：
  8.0

反应信息

• 作为反应物：
  描述：

  tetramethyl 1,5-dimethyltetracyclo[3.3.0^1,5.0^2,8.0^4,6]octane-3-exo,7-exo-dibromo-2,4,6,8-tetracarboxylate 在 sodium hydroxide 、 草酰氯 、 sodium iodide 作用下， 以 四氢呋喃 、 水 、 丙酮 为溶剂， 反应 35.0h， 生成 (2aR,4aS,7aR,7bS)-2a,7b-Dimethyl-5,7-dioxo-2a,7b-dihydro-6-oxa-cyclopenta[1,3]cyclopropa[1,2,3-cd]pentalene-2,3-dicarboxylic acid
  参考文献：
  名称：

  The Search for Homoaromatic Semibullvalenes. 5.¹ 1,5-Dimethyl-2,4,6,8-semibullvalenetetracarboxylic Dianhydride

  摘要：

  The synthesis and study of a novel bisannelated semibullvalene that is calculated to be a neutral homoaromatic ground state molecule is presented. Through variable-temperature X-ray, C-13 solution-phase NMR, and C-13 solid-state CP-MAS NMR studies and by a modified Saunders' isotopic perturbation method, 1,5-dimethyl-2,4,6,8-semibullvalenetetracarboxylic dianhydride is shown to be a highly fluxional molecule that is not homoaromatic in the solution or solid states, The barrier to the Cope rearrangement of this dianhydride, in solution, is estimated (from 125 MHz C-13 NMR data) to be less than 14 kJ mol(-1).

  DOI：

  10.1021/jo972010x
• 作为产物：
  描述：

  1,5-dimethyl 2,4,6,8-tetramethoxycarbonylbicyclo[3.3.0]octane-3,7-dione 在 sodium tetrahydroborate 、 溴 、 三溴化磷 、 三乙胺 作用下， 以 四氢呋喃 、 水 、 苯 为溶剂， 反应 63.0h， 生成 tetramethyl 1,5-dimethyltetracyclo[3.3.0^1,5.0^2,8.0^4,6]octane-3-exo,7-exo-dibromo-2,4,6,8-tetracarboxylate
  参考文献：
  名称：

  The Search for Homoaromatic Semibullvalenes. 5.¹ 1,5-Dimethyl-2,4,6,8-semibullvalenetetracarboxylic Dianhydride

  摘要：

  The synthesis and study of a novel bisannelated semibullvalene that is calculated to be a neutral homoaromatic ground state molecule is presented. Through variable-temperature X-ray, C-13 solution-phase NMR, and C-13 solid-state CP-MAS NMR studies and by a modified Saunders' isotopic perturbation method, 1,5-dimethyl-2,4,6,8-semibullvalenetetracarboxylic dianhydride is shown to be a highly fluxional molecule that is not homoaromatic in the solution or solid states, The barrier to the Cope rearrangement of this dianhydride, in solution, is estimated (from 125 MHz C-13 NMR data) to be less than 14 kJ mol(-1).

  DOI：

  10.1021/jo972010x