4-bromo-2,3,6-trimethylpyridine N-oxide | 879133-19-4

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 吡啶及其衍生物
• 英文名称: 4-bromo-2,3,6-trimethylpyridine N-oxide
• 英文别名: 2,3,6-trimethyl-4-bromopyridine N-oxide；4-Bromo-2,3,6-trimethyl-1-oxo-1lambda~5~-pyridine；4-bromo-2,3,6-trimethyl-1-oxidopyridin-1-ium
• CAS: 879133-19-4
• 化学式: C₈H₁₀BrNO
• 分子量: 216.077
• InChiKey: UUVQNCCOVVESKR-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.7
• 重原子数：
  11
• 可旋转键数：
  0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.38
• 拓扑面积：
  25.5
• 氢给体数：
  0
• 氢受体数：
  1

反应信息

• 作为产物：
  描述：

  2,3,6-Trimethyl-4-nitropyridine N-oxide 在 乙酰溴 作用下， 以 氯仿 为溶剂， 反应 1.0h， 以71%的产率得到4-bromo-2,3,6-trimethylpyridine N-oxide
  参考文献：
  名称：

  1H, 13C and 15N NMR spectral and theoretical studies of some methyl and alkylamino derivatives of 4-halopyridine N-oxides

  摘要：

  Nine new and three earlier known 4-halogen (Cl and Br) substituted pyridine N-oxides have been prepared and their H-1, C-13 and N-15 NMR chemical shifts assigned based on PFG H-1, X (X = C-13 and N-15) HMQC and HMBC experiments as well as the comparison with our earlier results for substituted pyridine N-oxide derivatives. The N-15 resonances of the pyridine nitrogen are 27-40 ppm more shielded in 4-halo-2alkylamino-6-methyl-5-nitropyridine N-oxide than in parent 4-halopyridine N-oxide. According to quantum chemical ab initio HF/ 6-311G** calculations the amino tautomer of 4-chloro-2-methylamino-6-methyl-5-nitropyridine N-oxide is more stable than its imino form. Using B3LYP/6-311G** optimized structures both C-13 and N-15 shifts were calculated by density functional B3LYP/6-311G** CSGT methods for the amino and imino tautomers as well as for the dimeric structure for 4-chloro-2-methylamino-6-methyl-5-nitropyridine N-oxide. The 15N NMR and DFT calculations suggest the prevailing of the dimeric amino form for one congener, which is further supported by ESI-TOF MS data. (c) 2005 Elsevier B.V. All rights reserved.

  DOI：

  10.1016/j.molstruc.2005.01.065

文献信息

• 1H, 13C and 15N NMR spectral and theoretical studies of some methyl and alkylamino derivatives of 4-halopyridine N-oxides
  作者：K. Laihia、A. Puszko、J. Linnanto、E. Kolehmainen

  DOI：10.1016/j.molstruc.2005.01.065

  日期：2006.2

  Nine new and three earlier known 4-halogen (Cl and Br) substituted pyridine N-oxides have been prepared and their H-1, C-13 and N-15 NMR chemical shifts assigned based on PFG H-1, X (X = C-13 and N-15) HMQC and HMBC experiments as well as the comparison with our earlier results for substituted pyridine N-oxide derivatives. The N-15 resonances of the pyridine nitrogen are 27-40 ppm more shielded in 4-halo-2alkylamino-6-methyl-5-nitropyridine N-oxide than in parent 4-halopyridine N-oxide. According to quantum chemical ab initio HF/ 6-311G** calculations the amino tautomer of 4-chloro-2-methylamino-6-methyl-5-nitropyridine N-oxide is more stable than its imino form. Using B3LYP/6-311G** optimized structures both C-13 and N-15 shifts were calculated by density functional B3LYP/6-311G** CSGT methods for the amino and imino tautomers as well as for the dimeric structure for 4-chloro-2-methylamino-6-methyl-5-nitropyridine N-oxide. The 15N NMR and DFT calculations suggest the prevailing of the dimeric amino form for one congener, which is further supported by ESI-TOF MS data. (c) 2005 Elsevier B.V. All rights reserved.