(4S)-Methyl 2-(N-benzoylamino)-4-(benzyloxy)-(2E)-pentenoate | 149287-48-9

• 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: (4S)-Methyl 2-(N-benzoylamino)-4-(benzyloxy)-(2E)-pentenoate
• CAS: 149287-48-9
• 化学式: C₂₀H₂₁NO₄
• 分子量: 339.391
• InChiKey: KBXJGCZGBSSCMZ-VUODPORTSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.08
• 重原子数：
  25.0
• 可旋转键数：
  7.0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.2
• 拓扑面积：
  64.63
• 氢给体数：
  1.0
• 氢受体数：
  4.0

反应信息

• 作为反应物：
  描述：

  (4S)-Methyl 2-(N-benzoylamino)-4-(benzyloxy)-(2E)-pentenoate 在 三乙烯二胺 、 N-溴代丁二酰亚胺(NBS) 作用下， 生成 (2Z,4S)-Methyl 2-(N-benzoylamino)-4-(benzyloxy)-3-bromo-2-pentenoate 、 (2E,4S)-Methyl 2-(N-benzoylamino)-4-(benzyloxy)-3-bromo-2-pentenoate
  参考文献：
  名称：

  Stereoselective bromination of dehydroamino acids with controllable retention or inversion of olefin configuration

  摘要：

  Dehydroamino acid esters react with brominating reagents to produce syn-a-bromo imines as the major products, which undergo tautomerization to mixtures of the diastereomeric (E)- and (Z)-beta-bromo-alpha,beta-dehydroamino acids upon treatment with base. Herein, we examine the characteristics of dehydroamino acid substrates 1 that affect both the diastereofacial selectivity of the bromination and the configuration of the resulting olefin product(s) 3. In these studies, we demonstrate E- and Z-diastereoselectivity for this reaction using kinetic and thermodynamic reaction conditions. Z-Vinyl bromides were shown to be the thermodynamically more stable products and were formed from the kinetic E-isomers by DABCO-induced isomerization. High levels of kinetic E-selectivity were obtained by treatment of the intermediate alpha-bromo imines with hindered amine bases such as 2,2,6,6-tetramethylpiperidine or sodium hexamethyldisilazide. The reaction conditions detailed herein allow for the stereodivergent preparation of both E- and Z-vinyl bromide products from either diastereomeric E- or Z-olefin starting material with useful levels of diastereoselectivity.

  DOI：

  10.1021/jo00068a047
• 作为产物：
  描述：

  methyl (S)-2-(benzyloxy)propanoate 在 二异丁基氢化铝 、 lithium diisopropyl amide 作用下， 以 四氢呋喃 、 乙醚 、 正己烷 为溶剂， 反应 4.0h， 生成 (4S)-Methyl 2-(N-benzoylamino)-4-(benzyloxy)-(2E)-pentenoate
  参考文献：
  名称：

  Stereoselective bromination of dehydroamino acids with controllable retention or inversion of olefin configuration

  摘要：

  Dehydroamino acid esters react with brominating reagents to produce syn-a-bromo imines as the major products, which undergo tautomerization to mixtures of the diastereomeric (E)- and (Z)-beta-bromo-alpha,beta-dehydroamino acids upon treatment with base. Herein, we examine the characteristics of dehydroamino acid substrates 1 that affect both the diastereofacial selectivity of the bromination and the configuration of the resulting olefin product(s) 3. In these studies, we demonstrate E- and Z-diastereoselectivity for this reaction using kinetic and thermodynamic reaction conditions. Z-Vinyl bromides were shown to be the thermodynamically more stable products and were formed from the kinetic E-isomers by DABCO-induced isomerization. High levels of kinetic E-selectivity were obtained by treatment of the intermediate alpha-bromo imines with hindered amine bases such as 2,2,6,6-tetramethylpiperidine or sodium hexamethyldisilazide. The reaction conditions detailed herein allow for the stereodivergent preparation of both E- and Z-vinyl bromide products from either diastereomeric E- or Z-olefin starting material with useful levels of diastereoselectivity.

  DOI：

  10.1021/jo00068a047

文献信息

• Stereoselective bromination of dehydroamino acids with controllable retention or inversion of olefin configuration
  作者：Robert S. Coleman、Andrew J. Carpenter

  DOI：10.1021/jo00068a047

  日期：1993.7

  Dehydroamino acid esters react with brominating reagents to produce syn-a-bromo imines as the major products, which undergo tautomerization to mixtures of the diastereomeric (E)- and (Z)-beta-bromo-alpha,beta-dehydroamino acids upon treatment with base. Herein, we examine the characteristics of dehydroamino acid substrates 1 that affect both the diastereofacial selectivity of the bromination and the configuration of the resulting olefin product(s) 3. In these studies, we demonstrate E- and Z-diastereoselectivity for this reaction using kinetic and thermodynamic reaction conditions. Z-Vinyl bromides were shown to be the thermodynamically more stable products and were formed from the kinetic E-isomers by DABCO-induced isomerization. High levels of kinetic E-selectivity were obtained by treatment of the intermediate alpha-bromo imines with hindered amine bases such as 2,2,6,6-tetramethylpiperidine or sodium hexamethyldisilazide. The reaction conditions detailed herein allow for the stereodivergent preparation of both E- and Z-vinyl bromide products from either diastereomeric E- or Z-olefin starting material with useful levels of diastereoselectivity.