2-<1-methyl-4-(methylimino)-2-oxo-3-pivaloylazetidin-3-yl>-2,6-di-tert-butyl-5-pivaloyl-1,3-dioxin-4(2H)-one

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: 2-<1-methyl-4-(methylimino)-2-oxo-3-pivaloylazetidin-3-yl>-2,6-di-tert-butyl-5-pivaloyl-1,3-dioxin-4(2H)-one
• 英文别名: 3-[2,4-Ditert-butyl-5-(2,2-dimethylpropanoyl)-6-oxo-1,3-dioxin-2-yl]-3-(2,2-dimethylpropanoyl)-1-methyl-4-methyliminoazetidin-2-one
• 化学式: C₂₇H₄₂N₂O₆
• 分子量: 490.64
• InChiKey: MRGKLNQVLTYOST-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5.3
• 重原子数：
  35
• 可旋转键数：
  7
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.74
• 拓扑面积：
  102
• 氢给体数：
  0
• 氢受体数：
  7

反应信息

• 作为产物：
  描述：

  dipivaloylketene 反应 56.0h， 生成 2-<1-methyl-4-(methylimino)-2-oxo-3-pivaloylazetidin-3-yl>-2,6-di-tert-butyl-5-pivaloyl-1,3-dioxin-4(2H)-one
  参考文献：
  名称：

  Dipivaloylketene and its dimers. [2+4] Versus [2+2] cycloaddition reactions of .alpha.-oxo ketenes

  摘要：

  Dipivaloylketene (8) is generated by preparative flash vacuum pyrolysis of furandione 6. While dimerization of 8 in apolar and several polar solvents leads to the previously reported [2 + 4] dimer 7, dimerization in the presence of DMSO, tributylphosphine oxide, or pyridine instead surprisingly occurs across the C=O bond of the ketene function, affording dioxinone 9. This is a novel type of alpha-oxo ketene dimerization. The reversibility of both dimerizations and mechanistic pathways for the formation of 9 are discussed. Cycloaddition reactions of 8 with heterocumulenes 10a,b and 12a-c yield [2 + 4] cycloadducts 11a,b and 13a-c, respectively. Oxazinones 13a-c can add a second molecule of 8 to generate novel spiro heterocycles 14a-c. In contrast, oxo ketene 7 reacts with carbodiimides 12a,b, to furnish [2 + 2] adducts 15a,b. This is the first unequivocal example of a direct [2 + 2] cycloaddition reaction of an alpha-oxo ketene. The unexpected formation of these compounds was confirmed by X-ray crystallography (15a). General aspects of [2 + 2] versus [2 + 4] cycloaddition in alpha-oxo ketenes are discussed.

  DOI：

  10.1021/jo00052a018

文献信息

• Dipivaloylketene and its dimers. [2+4] Versus [2+2] cycloaddition reactions of .alpha.-oxo ketenes
  作者：C. Oliver Kappe、Gerald Faerber、Curt Wentrup、Gert Kollenz

  DOI：10.1021/jo00052a018

  日期：1992.12

  Dipivaloylketene (8) is generated by preparative flash vacuum pyrolysis of furandione 6. While dimerization of 8 in apolar and several polar solvents leads to the previously reported [2 + 4] dimer 7, dimerization in the presence of DMSO, tributylphosphine oxide, or pyridine instead surprisingly occurs across the C=O bond of the ketene function, affording dioxinone 9. This is a novel type of alpha-oxo ketene dimerization. The reversibility of both dimerizations and mechanistic pathways for the formation of 9 are discussed. Cycloaddition reactions of 8 with heterocumulenes 10a,b and 12a-c yield [2 + 4] cycloadducts 11a,b and 13a-c, respectively. Oxazinones 13a-c can add a second molecule of 8 to generate novel spiro heterocycles 14a-c. In contrast, oxo ketene 7 reacts with carbodiimides 12a,b, to furnish [2 + 2] adducts 15a,b. This is the first unequivocal example of a direct [2 + 2] cycloaddition reaction of an alpha-oxo ketene. The unexpected formation of these compounds was confirmed by X-ray crystallography (15a). General aspects of [2 + 2] versus [2 + 4] cycloaddition in alpha-oxo ketenes are discussed.