ethyl 2,4-dicyclohexanylacetoacetate | 144542-54-1

• 分子结构分类: 有机化合物 - 有机酸及其衍生物 - 酮酸及其衍生物
• 英文名称: ethyl 2,4-dicyclohexanylacetoacetate
• CAS: 144542-54-1
• 化学式: C₁₈H₃₀O₃
• 分子量: 294.434
• InChiKey: UKBUTQORFQKZGZ-UHFFFAOYSA-N

物化性质

• 沸点：
  393.7±15.0 °C(Predicted)
• 密度：
  1.011±0.06 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  4.29
• 重原子数：
  21.0
• 可旋转键数：
  6.0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.89
• 拓扑面积：
  43.37
• 氢给体数：
  0.0
• 氢受体数：
  3.0

反应信息

• 作为产物：
  描述：

  环己甲酰氯 在 2,2,6,6-tetramethylpiperidinyl-lithium 作用下， 反应 0.25h， 生成 ethyl 2,4-dicyclohexanylacetoacetate
  参考文献：
  名称：

  Ester homologation revisited: a reliable, higher yielding and better understood procedure

  摘要：

  Enolate anions 3 and 6, prepared via enolization of a-bromo and dibromo ketones 4 and 5 were converted m high yield to ynolate anions 10 by respective addition of lithium tetramethylpiperidide (to effect deprotonation, 3 --> 7) or butyllithium (to effect metal-halogen exchange, 6 --> 7). Mixtures of such enolates were abo obtainable from esters 1 m a large-scale (25 mmol) via in situ formation and addition of lithiodibromomethane (from methylene bromide and lithium tetramethylpiperidide), followed by treatment of the resulting adducts with lithium hexamethyldisilazide to ensure complete enolization. Addition of sec-butyllithium and n-butyllithium to effect ynolate anion formation, followed by quenching of the reaction mixtures into acidic ethanol, reproducibly afforded homologated esters 8 in 67-90% yield. Demonstrated for ethyl esters 1 having the carbethoxy moiety attached to primary, secondary, tertiary, aryl, and alkenyl groups, this general procedure provides a convenient, large-scale alternative to the classical Arndt-Eistert sequence.

  DOI：

  10.1021/jo00052a038