4-甲基-4H-吡喃 | 16855-95-1

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 吡喃
• 中文名称: 4-甲基-4H-吡喃
• 英文名称: 4-methyl-4H-pyran
• 英文别名: 4H-Pyran, 4-methyl-
• CAS: 16855-95-1
• 化学式: C₆H₈O
• 分子量: 96.1289
• InChiKey: SIPORUXLFVLCBQ-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.5
• 重原子数：
  7
• 可旋转键数：
  0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.33
• 拓扑面积：
  9.2
• 氢给体数：
  0
• 氢受体数：
  1

反应信息

• 作为反应物：
  描述：

  4-甲基-4H-吡喃 在 trityl tetrafluoroborate 作用下， 以 乙腈 为溶剂， 以73%的产率得到4-methylpyrylium tetrafluoroborate
  参考文献：
  名称：

  Taylor, Richard J. K.; Hemming, Karl; Medeiros, Edna Faria De, Journal of the Chemical Society. Perkin transactions I, 1995, # 19, p. 2385 - 2392

  摘要：

  DOI：
• 作为产物：
  描述：

  3-甲基戊二醛 在 盐酸 、 N,N-二乙基苯胺 作用下， 以 二氯甲烷 为溶剂， 反应 16.83h， 生成 4-甲基-4H-吡喃
  参考文献：
  名称：

  Taylor, Richard J. K.; Hemming, Karl; Medeiros, Edna Faria De, Journal of the Chemical Society. Perkin transactions I, 1995, # 19, p. 2385 - 2392

  摘要：

  DOI：

文献信息

• Isomerization and fragmentation of methylfuran ions and pyran ions in the gas phase
  作者：Rudiger Spilker、H.-F. Grutzmacher

  DOI：10.1002/oms.1210210803

  日期：1986.8

  AbstractThe mutual interconversion of the molecular ions [C5H6O]+ of 2‐methylfuran (1), 3‐methylfuran (2) and 4H‐pyran (3) before fragmentation to [C5H5O]+ ions has been studied by collisional activation spectrometry, by deuterium labelling, by the kinetic energy release during the fragmentation, by appearance energles and by a MNDO calculation of the minimum energy reaction path. The electron impact and collisional activation mass spectra show clearly that the molecular ions of 1–3 do not equilibrate prior to fragmentation, but that mostly pyrylium ions [C5H5O]+ arise by the loss of a H atom. This implies an irreversible isomerization of methylfuran ions 1 and 2 into pyran ions before fragmentation, in contrast to the isomerization of the related systems toluene ions/cycloheptatriene ions. Complete H/D scrambling is observed in deuterated methylfuran ions prior to the H/D loss that is associated with an iostope effect kH/kD = 1.67–2.16 for metastable ions. In contrast, no H/D scrambling has been observed in deuterated 4H‐pyran ions. However, the loss of a H atom from all metastable [C5H5O]+ ions gives rise to a flat‐topped peak in the mass‐analysed ion kinetic energy spectrum and a kinetic energy release (T50) of 26 ± 1.5 kJ mol−1. The MNDO calculation of the minimum energy reaction path reveals that methylfuran ions 1 and 2 favour a rearrangement into pyran ions before fragmentation into furfuryl ions, but that the energy barrier of the first rearrangement step is at least of the same height as the barrier for the dissociation of pyran ions into pyrylium ions. This agrees with the experimental results.
• SCHLOSSER M.; SCHEIDER P., ANGEW. CHEM., 1979, 91, NO 6, 515-517
  作者：SCHLOSSER M.、 SCHEIDER P.

  DOI：——

  日期：——