11,12-dicarbomethoxy-1,4a-etheno-2-oxo-2,3,4,4a-tetrahydro-1H-pyrido<2,1-b>benzoxazole

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 苯并恶唑啉
• 英文名称: 11,12-dicarbomethoxy-1,4a-etheno-2-oxo-2,3,4,4a-tetrahydro-1H-pyrido<2,1-b>benzoxazole
• 英文别名: Dimethyl 11-oxo-2-oxa-9-azatetracyclo[8.3.2.01,9.03,8]pentadeca-3,5,7,14-tetraene-14,15-dicarboxylate
• 化学式: C₁₇H₁₅NO₆
• 分子量: 329.309
• InChiKey: PSXILYIPWOWASR-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.2
• 重原子数：
  24
• 可旋转键数：
  4
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.35
• 拓扑面积：
  82.1
• 氢给体数：
  0
• 氢受体数：
  7

反应信息

• 作为产物：
  描述：

  2-甲基苯并唑 在 辛酸铑 sodium hydroxide 、 水 、 三乙胺 、 氯甲酸甲酯 作用下， 以 甲醇 、 苯 为溶剂， 反应 14.58h， 生成 11,12-dicarbomethoxy-1,4a-etheno-2-oxo-2,3,4,4a-tetrahydro-1H-pyrido<2,1-b>benzoxazole
  参考文献：
  名称：

  Cycloaddition reactions of pyridinium and related azomethine ylides

  摘要：

  The Rh(H)-catalyzed reaction of alpha-diazoacetophenone in the presence of 2-(methylthio)pyridine and dimethyl acetylenedicarboxylate gave 3-benzoyl-1,2-dicarbomethoxy-3,5-dihydro-5-(methylthio)-indolizine. The formation of the cycloadduct proceeds via a pyridinium ylide formed by attack of the nitrogen lone pair on the electrophilic keto carbenoid. A related cyclization occurred using 1-diazo-3-[(2-pyridyl)thio]-2-propanone. The Rh(II)-catalyzed reaction of 1-(3'-diazoacetonyl)-2-pyridone with DMAD was also found to give cycloadducts derived from an azomethine ylide. The initial reaction involves generation of the expected carbonyl ylide dipole by intramolecular cyclization of the keto carbenoid onto the oxygen atom of the amide group. A subsequent proton exchange generates the thermodynamically more stable azomethine ylide which is trapped by DMAD. Azomethine ylide cycloadducts derived from keto carbenoid cyclization onto a thiobenzoxazole are also formed. When 1-diazo-3-[(2-benzoxazolyl)thio]-2-propanone was used, the initially formed cycloadduct underwent a subsequent 1,3-sigmatropic thio shift. An analogous cyclization occurred using 2-(4-diazo-3-oxobutyl)benzoxazole. In addition to undergoing dipolar cycloaddition, the highly stabilized dipole formed from this benzoxazole loses a proton to produce a cyclic ketene N,O-acetal. This compound reacts further with DMAD to eventually produce a novel phenolic lactam whose structure was established by an X-ray crystal structure analysis.

  DOI：

  10.1021/jo00057a029

文献信息

• Padwa Albert, Austin David J., Precedo Laura, Zhi Lin, J. Org. Chem., 58 (1993) N 5, S 1144-1150
  作者：Padwa Albert, Austin David J., Precedo Laura, Zhi Lin

  DOI：——

  日期：——
• Cycloaddition reactions of pyridinium and related azomethine ylides
  作者：Albert Padwa、David J. Austin、Laura Precedo、Lin Zhi

  DOI：10.1021/jo00057a029

  日期：1993.2

  The Rh(H)-catalyzed reaction of alpha-diazoacetophenone in the presence of 2-(methylthio)pyridine and dimethyl acetylenedicarboxylate gave 3-benzoyl-1,2-dicarbomethoxy-3,5-dihydro-5-(methylthio)-indolizine. The formation of the cycloadduct proceeds via a pyridinium ylide formed by attack of the nitrogen lone pair on the electrophilic keto carbenoid. A related cyclization occurred using 1-diazo-3-[(2-pyridyl)thio]-2-propanone. The Rh(II)-catalyzed reaction of 1-(3'-diazoacetonyl)-2-pyridone with DMAD was also found to give cycloadducts derived from an azomethine ylide. The initial reaction involves generation of the expected carbonyl ylide dipole by intramolecular cyclization of the keto carbenoid onto the oxygen atom of the amide group. A subsequent proton exchange generates the thermodynamically more stable azomethine ylide which is trapped by DMAD. Azomethine ylide cycloadducts derived from keto carbenoid cyclization onto a thiobenzoxazole are also formed. When 1-diazo-3-[(2-benzoxazolyl)thio]-2-propanone was used, the initially formed cycloadduct underwent a subsequent 1,3-sigmatropic thio shift. An analogous cyclization occurred using 2-(4-diazo-3-oxobutyl)benzoxazole. In addition to undergoing dipolar cycloaddition, the highly stabilized dipole formed from this benzoxazole loses a proton to produce a cyclic ketene N,O-acetal. This compound reacts further with DMAD to eventually produce a novel phenolic lactam whose structure was established by an X-ray crystal structure analysis.