2-Methylazuleno[2,1-b]pyridine

• 分子结构分类: 有机化合物 - 碳氢化合物 - 不饱和烃
• 英文名称: 2-Methylazuleno[2,1-b]pyridine
• 化学式: C₁₄H₁₁N
• 分子量: 193.248
• InChiKey: CSGOITAZVBTTQA-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.6
• 重原子数：
  15
• 可旋转键数：
  0
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.07
• 拓扑面积：
  12.9
• 氢给体数：
  0
• 氢受体数：
  1

反应信息

• 作为产物：
  描述：

  甘菊环-2-胺; 环戊并环庚五烯-2-胺; 薁-2-胺 、 丁烯酮 在 palladium on activated charcoal 作用下， 以 xylene 为溶剂， 反应 2.0h， 以58%的产率得到2-Methylazuleno[2,1-b]pyridine
  参考文献：
  名称：

  On the Reactions of (Vinylimino)phosphoranes and Related Compounds. 27. A Short New Synthesis of Azuleno[2,1-b]pyridines and Azuleno-Annulated [n](2,4)Pyridinophanes

  摘要：

  A short new synthesis of azuleno[2,1-b]pyridines 6a-g consists of the reaction of 2-aminoazulene (4) with acyclic alpha,beta-unsaturated ketones and aldehydes in an enamine-alkylation process, subsequent condensation of the amino group with a carbonyl function, and dehydrogenation in the presence of Pd/C. Similarly, the reaction of 4 with alpha,beta-unsaturated cycloalkenones gives azuleno-annulated [n](2,4)pyridinophanes 12a-c (n = 9-7) and dihydrogenated analogue 11d (n = 6). Compound 11d is converted to azuleno-annulated [6](2,5)pyridinophane 12d by treatment with DDQ. H-1 NMR spectroscopy at various temperatures shows dynamic behavior for the oligomethylene chains of [7]- and [6](2,4)pyridinophanes 12c,d. The energy barriers (DELTAG(c)double dagger) for the bridge flipping are 10.8 kcal/mol (T(c), -30-degrees-C) for 12c and 18.1 kcal/mol (T(c), 90-degrees-C) for 12d. Although the strain of 12c,d increases as the chainlength becomes shorter, the pyridine ring of 12c,d can flex more easily than that of the corresponding unannulated [n] (2,4)pyridinophanes. The deformation of the pyridine ring of 12a-d is also suggested by red shifts of the UV and H-1 NMR spectra. The pK(a) values of 12a-d are independent of the size of the methylene bridge, suggesting that the energy differences between the protonated and nonprotonated forms are almost the same for 12a-d.

  DOI：

  10.1021/jo00085a018

文献信息

• On the Reactions of (Vinylimino)phosphoranes and Related Compounds. 27. A Short New Synthesis of Azuleno[2,1-b]pyridines and Azuleno-Annulated [n](2,4)Pyridinophanes
  作者：Makoto Nitta、Takuya Akie、Yukio Iino

  DOI：10.1021/jo00085a018

  日期：1994.3

  A short new synthesis of azuleno[2,1-b]pyridines 6a-g consists of the reaction of 2-aminoazulene (4) with acyclic alpha,beta-unsaturated ketones and aldehydes in an enamine-alkylation process, subsequent condensation of the amino group with a carbonyl function, and dehydrogenation in the presence of Pd/C. Similarly, the reaction of 4 with alpha,beta-unsaturated cycloalkenones gives azuleno-annulated [n](2,4)pyridinophanes 12a-c (n = 9-7) and dihydrogenated analogue 11d (n = 6). Compound 11d is converted to azuleno-annulated [6](2,5)pyridinophane 12d by treatment with DDQ. H-1 NMR spectroscopy at various temperatures shows dynamic behavior for the oligomethylene chains of [7]- and [6](2,4)pyridinophanes 12c,d. The energy barriers (DELTAG(c)double dagger) for the bridge flipping are 10.8 kcal/mol (T(c), -30-degrees-C) for 12c and 18.1 kcal/mol (T(c), 90-degrees-C) for 12d. Although the strain of 12c,d increases as the chainlength becomes shorter, the pyridine ring of 12c,d can flex more easily than that of the corresponding unannulated [n] (2,4)pyridinophanes. The deformation of the pyridine ring of 12a-d is also suggested by red shifts of the UV and H-1 NMR spectra. The pK(a) values of 12a-d are independent of the size of the methylene bridge, suggesting that the energy differences between the protonated and nonprotonated forms are almost the same for 12a-d.