N-methoxy-N,4-dimethylpent-3-enamide | 206996-05-6

• 分子结构分类: 有机化合物 - 有机酸及其衍生物 - 羧酸及其衍生物
• 英文名称: N-methoxy-N,4-dimethylpent-3-enamide
• CAS: 206996-05-6
• 化学式: C₈H₁₅NO₂
• 分子量: 157.213
• InChiKey: WZDOQUGEABEMFD-UHFFFAOYSA-N

物化性质

• 沸点：
  187.9±33.0 °C(Predicted)
• 密度：
  0.954±0.06 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  1.4
• 重原子数：
  11
• 可旋转键数：
  3
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.62
• 拓扑面积：
  29.5
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  N-methoxy-N,4-dimethylpent-3-enamide 在 4-二甲氨基吡啶 、 sodium tetrahydroborate 、 正丁基锂 、 ammonium cerium(IV) nitrate 、 三乙胺 、 叔丁醇 作用下， 以 四氢呋喃 、 甲醇 、 正己烷 、 二氯甲烷 、 乙腈 为溶剂， 反应 10.24h， 生成 紫草素
  参考文献：
  名称：

  A New Efficient Route for Multigram Asymmetric Synthesis of Alkannin and Shikonin

  摘要：

  A short and convergent approach for the synthesis of alkannin, shikonin and shikalkin is presented. A Hauser-type annulation of cyanophthalide 26 with enone 7 affords the complete aromatic system in just one step with concomitant attachment of the entire side chain. Subsequent Corey's oxazaborolidine mediated asymmetric reduction of the above advanced intermediate, leads to the required isomer in high enantiomeric excess. Finally, a selective and high yielding deprotection protocol furnishes the title compounds as pure crystalline precipitates. Thus, a multigram synthesis of shikonin, alkannin and shikalkin is achieved in high yield and enantioselectivity.

  DOI：

  10.1002/1521-3765(20020415)8:8<1795::aid-chem1795>3.0.co;2-v
• 作为产物：
  描述：

  4-甲基戊-3-烯腈 在 吡啶 、 sodium hydroxide 、 四溴化碳 、 三苯基膦 作用下， 以 甲醇 、 二氯甲烷 为溶剂， 反应 8.0h， 生成 N-methoxy-N,4-dimethylpent-3-enamide
  参考文献：
  名称：

  A New Efficient Route for Multigram Asymmetric Synthesis of Alkannin and Shikonin

  摘要：

  A short and convergent approach for the synthesis of alkannin, shikonin and shikalkin is presented. A Hauser-type annulation of cyanophthalide 26 with enone 7 affords the complete aromatic system in just one step with concomitant attachment of the entire side chain. Subsequent Corey's oxazaborolidine mediated asymmetric reduction of the above advanced intermediate, leads to the required isomer in high enantiomeric excess. Finally, a selective and high yielding deprotection protocol furnishes the title compounds as pure crystalline precipitates. Thus, a multigram synthesis of shikonin, alkannin and shikalkin is achieved in high yield and enantioselectivity.

  DOI：

  10.1002/1521-3765(20020415)8:8<1795::aid-chem1795>3.0.co;2-v

文献信息

• Concise and Efficient Total Syntheses of Alkannin and Shikonin
  作者：K. C. Nicolaou、David Hepworth

  DOI：10.1002/(sici)1521-3773(19980403)37:6<839::aid-anie839>3.0.co;2-j

  日期：1998.4.3

  Two enantiomic natural products with wound-healing properties, alkannin (1) and shikonin (2), are accessible by a short and efficient total synthesis. The success was achieved by a novel protecting system for masking of 5,8-dihydroxy-1,4-naphthoquinones (naphthazarins) and a highly stereoselective ketone reduction.
• A New Efficient Route for Multigram Asymmetric Synthesis of Alkannin and Shikonin
  作者：Elias A. Couladouros、Alexandros T. Strongilos、Vassilios P. Papageorgiou、Zoi F. Plyta

  DOI：10.1002/1521-3765(20020415)8:8<1795::aid-chem1795>3.0.co;2-v

  日期：2002.4.15

  A short and convergent approach for the synthesis of alkannin, shikonin and shikalkin is presented. A Hauser-type annulation of cyanophthalide 26 with enone 7 affords the complete aromatic system in just one step with concomitant attachment of the entire side chain. Subsequent Corey's oxazaborolidine mediated asymmetric reduction of the above advanced intermediate, leads to the required isomer in high enantiomeric excess. Finally, a selective and high yielding deprotection protocol furnishes the title compounds as pure crystalline precipitates. Thus, a multigram synthesis of shikonin, alkannin and shikalkin is achieved in high yield and enantioselectivity.