5,6-diethynyl-2,4-dimethoxypyrimidine | 216979-57-6

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 三嗪类
• 英文名称: 5,6-diethynyl-2,4-dimethoxypyrimidine
• 英文别名: 4,5-Diethynyl-2,6-dimethoxypyrimidine
• CAS: 216979-57-6
• 化学式: C₁₀H₈N₂O₂
• 分子量: 188.186
• InChiKey: AQJDDMXJEDESNX-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.3
• 重原子数：
  14
• 可旋转键数：
  4
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.2
• 拓扑面积：
  44.2
• 氢给体数：
  0
• 氢受体数：
  4

反应信息

• 作为反应物：
  描述：

  5,6-diethynyl-2,4-dimethoxypyrimidine 在 1,4-环己二烯 作用下， 以 二甲基亚砜 为溶剂， 生成 2,4-dimethoxy-quinazoline
  参考文献：
  名称：

  10.1002/(sici)1521-3765(20000502)6:9<1555::aid-chem1555<3.3.co;2-d

  摘要：

  DOI：

  10.1002/(sici)1521-3765(20000502)6:9<1555::aid-chem1555<3.3.co;2-d
• 作为产物：
  描述：

  6-氯-2,4-甲氧基嘧啶 在 四(三苯基膦)钯 N-碘代丁二酰亚胺 、 氢氟酸 、 sodium fluoride 、 二异丙胺 、 三氟乙酸酐 作用下， 以 乙醇 、 水 、 三氟乙酸 为溶剂， 反应 5.3h， 生成 5,6-diethynyl-2,4-dimethoxypyrimidine
  参考文献：
  名称：

  Rapid Bergman Cyclization of 1,2-Diethynylheteroarenes

  摘要：

  The synthesis and cyclization of acyclic quinoxaline, pyridine, and pyrimidine enediynes (1-3) are described. These compounds were prepared using palladium(0) coupling of trimethylsilyl acetylene to o-dihalo- or o-halotriflic heteroarenes. All compounds were prepared in modest to good yields. The enediynes prepared were shown to undergo Bergman cyclization. Kinetics over a minimum of 3 half-lives were used to construct Arrhenius plots. Pyrimidine 3 was found to have an activation energy of 16.1 kcal/mol. Cyclization of the closest known aromatic analogue, o-diethynylbenzene (15), has E-a = 25.1 kcal/mol (Grissom, J. W.; Calkins, T. L.;McMillen, H. A.; Jiang, Y. J. Org. Chem. 1994, 59, 5833-5835). Pyridine 2 and quinoxaline 1 gave activation energies of 21.5 and 33.6 kcal/mol, respectively. The results illustrate that heteroarenes can be used to activate Bergman cyclization. We expect these compounds to play an important role in furthering the understanding of Bergman cyclization and in aiding the development of new biologically significant enediynes.

  DOI：

  10.1021/jo980879p