3-(2-allylbenzylidene)phthalide

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 异香豆素
• 英文名称: 3-(2-allylbenzylidene)phthalide
• 英文别名: 3-(2-allylbenzylidene)-2-benzofuran-1(3H)-one；(3Z)-3-[(2-prop-2-enylphenyl)methylidene]-2-benzofuran-1-one
• 化学式: C₁₈H₁₄O₂
• 分子量: 262.308
• InChiKey: APGVSLZXIXOPAY-ATVHPVEESA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.5
• 重原子数：
  20
• 可旋转键数：
  3
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.06
• 拓扑面积：
  26.3
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  3-(2-allylbenzylidene)phthalide 在 硫酸 、 sodium hydride 、 叠氮化三(二乙胺基)溴化 作用下， 以 四氢呋喃 、 正己烷 为溶剂， 反应 108.0h， 生成 ethyl 2-(3a,4-dihydro-3H-indeno<1,2-c>pyrazole-8b-carbonyl)benzoate
  参考文献：
  名称：

  Model Studies Directed toward the Total Synthesis of (±)-Ribasine. A Tandem Cyclization−Cycloaddition Route Leading to the Core Skeleton

  摘要：

  A series of alpha-diazo-beta-(o-carbomethoxy)-substituted aryl ketones were prepared and employed as model systems for a synthetic approach toward the alkaloid ribasine. Six-membered ring carbonyl ylide dipoles were generated by treating the diazoketones with a rhodium(II) catalyst. The initially formed dipole was trapped using a variety of dipolarophiles including N-benzylidene methylamine. The Rh(II)-catalyzed behavior of ethyl 2-diazo-3-(2-formylphenyl)-3-oxo-propionate was also studied to probe the chemoselectivity of the reaction. The major products isolated are derived from bimolecular trapping of the carbonyl ylide dipole, as well as intramolecular C-H insertion of the rhodium carbenoid into the aldehydic hydrogen. Changing the catalyst from Rh(II) trifluoroacetate to Rh(II) acetate caused a significant alteration in product distribution. A study of the tandem cyclization-cycloaddition reaction of an o-allyl phenyl substituted diazoketone was also carried out. An unexpected low-temperature intramolecular dipolar cycloaddition of the diazo group across the neighboring pi-bond first occurred, followed by nitrogen extrusion to give products derived from a 1,3-biradical intermediate. By subjecting the diazoketone to the Rh(II) catalyst at 110 degrees C, it was possible to prepare the carbonyl ylide derived cycloadduct in high yield. This result provides good precedent for the future implementation of the cycloaddition strategy toward the synthesis of ribasine.

  DOI：

  10.1021/jo990136j
• 作为产物：
  描述：

  邻溴苯乙酸 在 四(三苯基膦)钯 、 sodium acetate 作用下， 以 苯 为溶剂， 反应 4.0h， 生成 3-(2-allylbenzylidene)phthalide
  参考文献：
  名称：

  Model Studies Directed toward the Total Synthesis of (±)-Ribasine. A Tandem Cyclization−Cycloaddition Route Leading to the Core Skeleton

  摘要：

  A series of alpha-diazo-beta-(o-carbomethoxy)-substituted aryl ketones were prepared and employed as model systems for a synthetic approach toward the alkaloid ribasine. Six-membered ring carbonyl ylide dipoles were generated by treating the diazoketones with a rhodium(II) catalyst. The initially formed dipole was trapped using a variety of dipolarophiles including N-benzylidene methylamine. The Rh(II)-catalyzed behavior of ethyl 2-diazo-3-(2-formylphenyl)-3-oxo-propionate was also studied to probe the chemoselectivity of the reaction. The major products isolated are derived from bimolecular trapping of the carbonyl ylide dipole, as well as intramolecular C-H insertion of the rhodium carbenoid into the aldehydic hydrogen. Changing the catalyst from Rh(II) trifluoroacetate to Rh(II) acetate caused a significant alteration in product distribution. A study of the tandem cyclization-cycloaddition reaction of an o-allyl phenyl substituted diazoketone was also carried out. An unexpected low-temperature intramolecular dipolar cycloaddition of the diazo group across the neighboring pi-bond first occurred, followed by nitrogen extrusion to give products derived from a 1,3-biradical intermediate. By subjecting the diazoketone to the Rh(II) catalyst at 110 degrees C, it was possible to prepare the carbonyl ylide derived cycloadduct in high yield. This result provides good precedent for the future implementation of the cycloaddition strategy toward the synthesis of ribasine.

  DOI：

  10.1021/jo990136j

文献信息

• Model Studies Directed toward the Total Synthesis of (±)-Ribasine. A Tandem Cyclization−Cycloaddition Route Leading to the Core Skeleton
  作者：Albert Padwa、Laura Precedo、Mark A. Semones

  DOI：10.1021/jo990136j

  日期：1999.5.1

  A series of alpha-diazo-beta-(o-carbomethoxy)-substituted aryl ketones were prepared and employed as model systems for a synthetic approach toward the alkaloid ribasine. Six-membered ring carbonyl ylide dipoles were generated by treating the diazoketones with a rhodium(II) catalyst. The initially formed dipole was trapped using a variety of dipolarophiles including N-benzylidene methylamine. The Rh(II)-catalyzed behavior of ethyl 2-diazo-3-(2-formylphenyl)-3-oxo-propionate was also studied to probe the chemoselectivity of the reaction. The major products isolated are derived from bimolecular trapping of the carbonyl ylide dipole, as well as intramolecular C-H insertion of the rhodium carbenoid into the aldehydic hydrogen. Changing the catalyst from Rh(II) trifluoroacetate to Rh(II) acetate caused a significant alteration in product distribution. A study of the tandem cyclization-cycloaddition reaction of an o-allyl phenyl substituted diazoketone was also carried out. An unexpected low-temperature intramolecular dipolar cycloaddition of the diazo group across the neighboring pi-bond first occurred, followed by nitrogen extrusion to give products derived from a 1,3-biradical intermediate. By subjecting the diazoketone to the Rh(II) catalyst at 110 degrees C, it was possible to prepare the carbonyl ylide derived cycloadduct in high yield. This result provides good precedent for the future implementation of the cycloaddition strategy toward the synthesis of ribasine.