cis-3-chloro-4-ethyl-3,4-dihydro-2H-1-benzopyran-2-one | 133380-05-9

• 分子结构分类: 有机化合物 - 苯丙烷和聚酮 - 3,4-二氢香豆素
• 英文名称: cis-3-chloro-4-ethyl-3,4-dihydro-2H-1-benzopyran-2-one
• 英文别名: (3S,4S)-3-chloro-4-ethyl-3,4-dihydrochromen-2-one
• CAS: 133380-05-9；133380-06-0
• 化学式: C₁₁H₁₁ClO₂
• 分子量: 210.66
• InChiKey: PNRZYBPPZVBOME-XVKPBYJWSA-N

物化性质

• 沸点：
  289.7±39.0 °C(Predicted)
• 密度：
  1.24±0.1 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  3.1
• 重原子数：
  14
• 可旋转键数：
  1
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.36
• 拓扑面积：
  26.3
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  cis-3-chloro-4-ethyl-3,4-dihydro-2H-1-benzopyran-2-one 在 sodium acetate 作用下， 以 乙酸酐 为溶剂， 反应 0.2h， 以52%的产率得到4-甲基香豆素
  参考文献：
  名称：

  Reaction of 3-halogeno-2H-1-benzopyran-2-ones with organometallic compounds. Synthesis of 4-Alkyl-2H-1-benzopyran-2-ones. X-Ray molecular structure of 3-bromo-3,4-dihydro-4-isopropylcoumarin

  摘要：

  3-Halogeno-2H-1-benzopyran-2-ones react with magnesium, lithium, aluminium and copper derivatives to give 3,4-dihydrocoumarins and 3-(o-hydroxyphenyl)propenols as major products. The nature and the ratio of the products in the final mixture depend on the solvent and on the organometallic reagent. Grignard derivatives yield 1,4-monoalkylation compounds in tetrahydrofuran (THF) or 1,2-dialkylation derivatives in toluene. In some cases the dehalogenation competes with the 1,2-alkylation process in the reactions with alkyllithiums. The presence of the halogen at C-3 increases the reductive ability of organoaluminiums. In general, the reaction with lithium dialkylcuprates leads to complex mixtures of products. The 4-alkyl-3-halogeno-3,4-dihydrocoumarins obtained undergo dehydrohalogenation easily, and lead to 4-alkylcoumarins in good yields. The tandem alkylation-dehydrohalogenation of 3-halogeno-2H-1-benzopyran-2-ones constitutes a versatile synthesis of 4-alkylcoumarins.

  DOI：

  10.1039/p19910000203
• 作为产物：
  描述：

  3-氯香豆素 以 乙醚 为溶剂， 反应 0.5h， 以56.1%的产率得到cis-3-chloro-4-ethyl-3,4-dihydro-2H-1-benzopyran-2-one
  参考文献：
  名称：

  Reaction of 3-halogeno-2H-1-benzopyran-2-ones with organometallic compounds. Synthesis of 4-Alkyl-2H-1-benzopyran-2-ones. X-Ray molecular structure of 3-bromo-3,4-dihydro-4-isopropylcoumarin

  摘要：

  3-Halogeno-2H-1-benzopyran-2-ones react with magnesium, lithium, aluminium and copper derivatives to give 3,4-dihydrocoumarins and 3-(o-hydroxyphenyl)propenols as major products. The nature and the ratio of the products in the final mixture depend on the solvent and on the organometallic reagent. Grignard derivatives yield 1,4-monoalkylation compounds in tetrahydrofuran (THF) or 1,2-dialkylation derivatives in toluene. In some cases the dehalogenation competes with the 1,2-alkylation process in the reactions with alkyllithiums. The presence of the halogen at C-3 increases the reductive ability of organoaluminiums. In general, the reaction with lithium dialkylcuprates leads to complex mixtures of products. The 4-alkyl-3-halogeno-3,4-dihydrocoumarins obtained undergo dehydrohalogenation easily, and lead to 4-alkylcoumarins in good yields. The tandem alkylation-dehydrohalogenation of 3-halogeno-2H-1-benzopyran-2-ones constitutes a versatile synthesis of 4-alkylcoumarins.

  DOI：

  10.1039/p19910000203