Methyl 4,4-dimethyl-3-hydroxy-2-methylene-1-pentanoate | 171288-90-7

• 分子结构分类: 有机化合物 - 有机酸及其衍生物 - 羟基酸及其衍生物
• 英文名称: Methyl 4,4-dimethyl-3-hydroxy-2-methylene-1-pentanoate
• 英文别名: methyl 3-hydroxy-4,4-dimethyl-2-methylidenepentanoate
• CAS: 171288-90-7
• 化学式: C₉H₁₆O₃
• 分子量: 172.224
• InChiKey: LQKPWCOUVJEOBK-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.12
• 重原子数：
  12.0
• 可旋转键数：
  2.0
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.67
• 拓扑面积：
  46.53
• 氢给体数：
  1.0
• 氢受体数：
  3.0

反应信息

• 作为反应物：
  描述：

  Methyl 4,4-dimethyl-3-hydroxy-2-methylene-1-pentanoate 、 对硝基苯甲酸 在 三乙胺 、 三苯基膦 、 偶氮二甲酸二乙酯 作用下， 以 四氢呋喃 为溶剂， 以60%的产率得到Methyl (E)-4,4-dimethyl-2-<<(4-nitrobenzoyl)oxy>methyl>-2-pentenoate
  参考文献：
  名称：

  Synthesis of Monoprotected 2-Alkylidene-1,3-propanediols by an Unusual SN2' Mitsunobu Reaction

  摘要：

  A simple and efficient route to monoprotected (E)- and (Z)-2-alkylidene-1,3-propanediols is described. The key step involves an unusual regio- and stereoselective S(N)2' Mitsunobu reaction of substituted 3-hydroxy-2-methylenealkanoates which are readily available from a Baylis-Hillman reaction between methyl acrylate and an aldehyde. These allylic alcohols, when treated with PPh(3), a carboxylic acid, and DEAD in THF at temperatures ranging from -40 degrees C to 22 degrees C, produced the corresponding 2-alkylidene-3-hydroxypropanoate derivatives (or (E)-2-(hydroxymethyl)-3-substituted-2-alkenoate derivatives) in >70% with S(N)2':S(N)2 ratio of 22:1 to >50:1. It was found that weak and bulky carboxylic acids and low temperatures favor S(N)2' addition. The reaction conditions were effective for alkyl substituted derivatives, but the addition of Et(3)N to the Mitsunobu conditions was necessary to improve the S(N)2':S(N)2 ratios for the vinyl 19 and phenyl 20 derivatives. The monoprotected (Z)- and (E)-2-alkylidene-1,3-propanediols can be efficiently synthesized by a three-step sequence involving either a transesterification, protection, and DIBAL-H reduction (>80% overall yield) or by the chemoselective reduction, protection, and ester cleavage (67% overall yield).

  DOI：

  10.1021/jo00126a046
• 作为产物：
  描述：

  特戊醛 、 丙烯酸甲酯（MA） 在 1,8-二氮杂双环[5.4.0]十一碳-7-烯 作用下， 反应 70.0h， 以20%的产率得到Methyl 4,4-dimethyl-3-hydroxy-2-methylene-1-pentanoate
  参考文献：
  名称：

  Superior amine catalysts for the Baylis–Hillman reaction: the use of DBU and its implications†

  摘要：

  DBU通常被认为是一种位阻大且非亲核性的碱，但实际上它是Baylis-Hillman反应的最佳催化剂，能够比使用DABCO或3HQD更快速地提供加合物；使用这种催化剂可以扩大Baylis-Hillman反应的应用范围，并且讨论了这一发现的含义。

  DOI：

  10.1039/a907754e