3-(3-guaiazulenyl)-2-benzofuran-1(3H)-one

• 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: 3-(3-guaiazulenyl)-2-benzofuran-1(3H)-one
• 英文别名: 3-(3,8-dimethyl-5-propan-2-ylazulen-1-yl)-3H-2-benzofuran-1-one
• 化学式: C₂₃H₂₂O₂
• 分子量: 330.426
• InChiKey: WMINWAKYFKZCGA-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5.9
• 重原子数：
  25
• 可旋转键数：
  2
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.26
• 拓扑面积：
  26.3
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为产物：
  描述：

  愈创奥 在 hexafluorophosphoric acid 、 碳酸氢钠 作用下， 以 乙醚 为溶剂， 反应 1.5h， 生成 3-(3-guaiazulenyl)-2-benzofuran-1(3H)-one
  参考文献：
  名称：

  Reaction of guaiazulene with o-formylbenzoic acid in diethyl ether (or methanol) in the presence of hexafluorophosphoric acid: comparative studies on 1H and 13C NMR spectral properties of 3-guaiazulenylmethylium- and 3-guaiazulenium-ion structures

  摘要：

  Reaction of guaiazulene (1) with o-formylbenzoic acid (2) in diethyl ether in the presence of hexafluorophosphoric acid at 25 degrees C for 90 min gives the corresponding monocarbenium-ion compound, [2-(carboxy)phenyl](3-guaiazulenyl)methylium hexafluorophosphate (3), quantitatively, which upon treatment with aq NaHCO3 leads to 3-(3-guaiazulenyl)-2-benzofuran-1(3H)-one (5) in 96% isolated yield. Similarly, reaction of 1 with 2 in methanol under the same conditions as the above reaction affords two kinds of inseparable monocarbenium-ion compounds, 3 and (3-guaiazulenyl)[2-(methoxycarbonyl)phenyl]methylium hexafluorophosphate (4) with an equilibrium between them, which upon reaction with a solution of NaBH4 in ethanol at 25 degrees C for 30 min leads to 5 in 46% isolated yield and (3-guaiazulenyl)[2- (methoxycarbonyl)phenyl]methane (6) in 37% isolated yield. Along with the H-1 and C-13 NMR spectral properties of a solution of 5 in trifluoroacetic acid-d(1) at 25 degrees C, whose molecular structure is converted to a ca. 1: 1 equilibrium mixture of 7 possessing a partial structure of the 3-guaiazulenylmethylium-ion and 8 possessing a partial structure of the 3-guaiazulenium-ion, comparative studies on the H-1 and C-13 NMR spectral properties of 7 and 8 with those of the monocarbeniurn-ion compound, (3-guaiazulenyl)[4-(methoxycarbonyl)phenyl]methylium hexafluorophosphate (A), 5, and 6 are reported. From these NMR studies, it can be inferred that the positive charge of the 3-guaiazulenylmethylium-ion part of 7 apparently is transferred to the seven-membered ring, generating a resonance form of the 3-guaiazulenyliumion structure eta, and the same result can be inferred for the previously documented monocarbenium-ion compounds A-I. Moreover, referring to a comparative study on the C-C bond lengths of A observed by the X-ray crystallographic analysis with those of the optimized (3-guaiazulenyl)[4-(methoxycarbonyl)]phenyllmethylium-ion structure for A calculated by a WinMOPAC (Ver. 3.0) program using PM3, AMI, or MNDOD as a semiempirical Hamiltonian, the optimized [2-(carboxy)phenyl](3-guaiazulenyl)methylium-ion structure for 3 calculated using PM3 is described. (c) 2007 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.tet.2006.12.094

文献信息

• Reaction of guaiazulene with o-formylbenzoic acid in diethyl ether (or methanol) in the presence of hexafluorophosphoric acid: comparative studies on 1H and 13C NMR spectral properties of 3-guaiazulenylmethylium- and 3-guaiazulenium-ion structures
  作者：Shin-ichi Takekuma、Kazutaka Sonoda、Chika Fukuhara、Toshie Minematsu

  DOI：10.1016/j.tet.2006.12.094

  日期：2007.3

  Reaction of guaiazulene (1) with o-formylbenzoic acid (2) in diethyl ether in the presence of hexafluorophosphoric acid at 25 degrees C for 90 min gives the corresponding monocarbenium-ion compound, [2-(carboxy)phenyl](3-guaiazulenyl)methylium hexafluorophosphate (3), quantitatively, which upon treatment with aq NaHCO3 leads to 3-(3-guaiazulenyl)-2-benzofuran-1(3H)-one (5) in 96% isolated yield. Similarly, reaction of 1 with 2 in methanol under the same conditions as the above reaction affords two kinds of inseparable monocarbenium-ion compounds, 3 and (3-guaiazulenyl)[2-(methoxycarbonyl)phenyl]methylium hexafluorophosphate (4) with an equilibrium between them, which upon reaction with a solution of NaBH4 in ethanol at 25 degrees C for 30 min leads to 5 in 46% isolated yield and (3-guaiazulenyl)[2- (methoxycarbonyl)phenyl]methane (6) in 37% isolated yield. Along with the H-1 and C-13 NMR spectral properties of a solution of 5 in trifluoroacetic acid-d(1) at 25 degrees C, whose molecular structure is converted to a ca. 1: 1 equilibrium mixture of 7 possessing a partial structure of the 3-guaiazulenylmethylium-ion and 8 possessing a partial structure of the 3-guaiazulenium-ion, comparative studies on the H-1 and C-13 NMR spectral properties of 7 and 8 with those of the monocarbeniurn-ion compound, (3-guaiazulenyl)[4-(methoxycarbonyl)phenyl]methylium hexafluorophosphate (A), 5, and 6 are reported. From these NMR studies, it can be inferred that the positive charge of the 3-guaiazulenylmethylium-ion part of 7 apparently is transferred to the seven-membered ring, generating a resonance form of the 3-guaiazulenyliumion structure eta, and the same result can be inferred for the previously documented monocarbenium-ion compounds A-I. Moreover, referring to a comparative study on the C-C bond lengths of A observed by the X-ray crystallographic analysis with those of the optimized (3-guaiazulenyl)[4-(methoxycarbonyl)]phenyllmethylium-ion structure for A calculated by a WinMOPAC (Ver. 3.0) program using PM3, AMI, or MNDOD as a semiempirical Hamiltonian, the optimized [2-(carboxy)phenyl](3-guaiazulenyl)methylium-ion structure for 3 calculated using PM3 is described. (c) 2007 Elsevier Ltd. All rights reserved.