1-(1-hydroxyethyl)-9H-xanthen-9-one

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 苯并吡喃
• 英文名称: 1-(1-hydroxyethyl)-9H-xanthen-9-one
• 英文别名: 1-(1-Hydroxyethyl)xanthen-9-one；1-(1-hydroxyethyl)xanthen-9-one
• 化学式: C₁₅H₁₂O₃
• 分子量: 240.258
• InChiKey: CJMLJFBNPBQRRN-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.5
• 重原子数：
  18
• 可旋转键数：
  1
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.13
• 拓扑面积：
  46.5
• 氢给体数：
  1
• 氢受体数：
  3

反应信息

• 作为产物：
  描述：

  2-氯苯甲酸 在 氢氧化钾 、 N-溴代丁二酰亚胺(NBS) 、 硫酸 、 铜 、 potassium carbonate 、 copper(II) iodide 、 溶剂黄146 、 过氧化苯甲酰 作用下， 以 四氯化碳 为溶剂， 反应 17.17h， 生成 1-(1-hydroxyethyl)-9H-xanthen-9-one
  参考文献：
  名称：

  Photochemistry of the 9-Hydroxyxanthenyl Radical in the Laser-Jet: Evidence for Photochemically Induced, Regioselective Radical Coupling

  摘要：

  The conventional irradiation (low intensity) of xanthone in ethanol was observed to produce pinacol 3 by photoreductive coupling and 9-hydroxy-9-(1-hydroxyethyl)-9H-xanthene (4) by head-to-head cross-coupling between the resultant 9-hydroxyxanthenyl (2) and 1-hydroxyethyl radicals. Under laser-jet conditions (high intensity), in addition to products 3 and 4, 3-(1-hydroxyethyl)-9H-xanthen-9-one (5d) was obtained as the major head-to-tail cross-coupling product. The observed dependence of the product ratio of 4 and 5d on the irradiation intensity is rationalized in terms of the higher spin density in the aryl rings, particularly at the 3-position (para to the hydroxy-substituted carbon atom), of the electronically excited 9-hydroxyxanthenyl radical (2'). For the ground state radical 2, as expected, the majority of spin density resides at the hydroxy-substituted carbon atom and, thus, constitutes the precursor to the head-to-head cross-coupling product 4. The theoretical spin densities for the ground and excited state 9-hydroxyxanthenyl radicals 2, calculated by semiempirical MO methods (PM3), indicate that upon photoexcitation the electron density in the SOMO shifts from the hydroxy-substituted radical center (ground state) to the aromatic pi-system (first excited state) and is concentrated at the 1a- and 3-positions.

  DOI：

  10.1021/ja00088a002

文献信息

• Photochemistry of the 9-Hydroxyxanthenyl Radical in the Laser-Jet: Evidence for Photochemically Induced, Regioselective Radical Coupling
  作者：Waldemar Adam、Fumio Kita

  DOI：10.1021/ja00088a002

  日期：1994.5

  The conventional irradiation (low intensity) of xanthone in ethanol was observed to produce pinacol 3 by photoreductive coupling and 9-hydroxy-9-(1-hydroxyethyl)-9H-xanthene (4) by head-to-head cross-coupling between the resultant 9-hydroxyxanthenyl (2) and 1-hydroxyethyl radicals. Under laser-jet conditions (high intensity), in addition to products 3 and 4, 3-(1-hydroxyethyl)-9H-xanthen-9-one (5d) was obtained as the major head-to-tail cross-coupling product. The observed dependence of the product ratio of 4 and 5d on the irradiation intensity is rationalized in terms of the higher spin density in the aryl rings, particularly at the 3-position (para to the hydroxy-substituted carbon atom), of the electronically excited 9-hydroxyxanthenyl radical (2'). For the ground state radical 2, as expected, the majority of spin density resides at the hydroxy-substituted carbon atom and, thus, constitutes the precursor to the head-to-head cross-coupling product 4. The theoretical spin densities for the ground and excited state 9-hydroxyxanthenyl radicals 2, calculated by semiempirical MO methods (PM3), indicate that upon photoexcitation the electron density in the SOMO shifts from the hydroxy-substituted radical center (ground state) to the aromatic pi-system (first excited state) and is concentrated at the 1a- and 3-positions.