4-(5-bromopentoxy)-6-methylpyran-2-one | 136721-22-7

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 吡喃
• 英文名称: 4-(5-bromopentoxy)-6-methylpyran-2-one
• CAS: 136721-22-7
• 化学式: C₁₁H₁₅BrO₃
• 分子量: 275.142
• InChiKey: JBEFLGKMGPKXAI-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.89
• 重原子数：
  15.0
• 可旋转键数：
  6.0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.55
• 拓扑面积：
  39.44
• 氢给体数：
  0.0
• 氢受体数：
  3.0

反应信息

• 作为反应物：
  描述：

  4-(5-bromopentoxy)-6-methylpyran-2-one 在 硫酸 作用下， 以 乙醇 为溶剂， 生成 4-(5-hydroxypentoxy)-6-methylpyran-2-one
  参考文献：
  名称：

  Intramolecular photochemical reactions of 4-(.omega.-alkenyloxy)-6-methyl-2-pyrones having an alkoxycarbonyl group at the olefinic carbon chain

  摘要：

  Photochemical reactions of 4-(omega-alkenyloxy)-6-methyl-2-pyrones 4-8 were investigated. Photosensitized reactions of 2-pyrones 4-6 gave intramolecular [2 + 2] cycloadducts 14-16 as oxatricyclic lactones, site-, regio- and stereospecifically, but 7 and 8 gave no products. On the other hand, direct irradiations of 4 and 5 afforded cyclobutenecarboxylic acids 19 and 20, respectively. The intramolecular cycloaddition mechanism was also explained from the excited state of 2-pyrone calculated by means of the MNDO-CI method.

  DOI：

  10.1021/jo00025a035
• 作为产物：
  描述：

  4-羟基-6-甲基-2-吡喃酮 、 1,5-二溴戊烷 在 三乙胺 作用下， 以 乙腈 为溶剂， 以49%的产率得到4-(5-bromopentoxy)-6-methylpyran-2-one
  参考文献：
  名称：

  Intramolecular photochemical reactions of 4-(.omega.-alkenyloxy)-6-methyl-2-pyrones having an alkoxycarbonyl group at the olefinic carbon chain

  摘要：

  Photochemical reactions of 4-(omega-alkenyloxy)-6-methyl-2-pyrones 4-8 were investigated. Photosensitized reactions of 2-pyrones 4-6 gave intramolecular [2 + 2] cycloadducts 14-16 as oxatricyclic lactones, site-, regio- and stereospecifically, but 7 and 8 gave no products. On the other hand, direct irradiations of 4 and 5 afforded cyclobutenecarboxylic acids 19 and 20, respectively. The intramolecular cycloaddition mechanism was also explained from the excited state of 2-pyrone calculated by means of the MNDO-CI method.

  DOI：

  10.1021/jo00025a035