(R)-(+)-2-isopropyl-5-methylhex-5-ene-1-carboxylic acid | 317801-61-9

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 脂肪酰基
• 英文名称: (R)-(+)-2-isopropyl-5-methylhex-5-ene-1-carboxylic acid
• 英文别名: (2R)-2-Isopropyl-5-methylhex-5-enoic acid；(2R)-5-methyl-2-propan-2-ylhex-5-enoic acid
• CAS: 317801-61-9
• 化学式: C₁₀H₁₈O₂
• 分子量: 170.252
• InChiKey: NVOBEWKGWWJTOA-SECBINFHSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.2
• 重原子数：
  12
• 可旋转键数：
  5
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.7
• 拓扑面积：
  37.3
• 氢给体数：
  1
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  (R)-(+)-2-isopropyl-5-methylhex-5-ene-1-carboxylic acid 在 lithium aluminium tetrahydride 作用下， 以 乙醚 为溶剂， 反应 1.0h， 以98%的产率得到(R)-(+)-2-isopropyl-5-methylhex-5-en-1-ol
  参考文献：
  名称：

  Asymmetric synthesis and Lewis acid mediated type II carbonyl ene cyclisations of (R)-2-isopropyl-5-methylhex-5-enal

  摘要：

  The asymmetric synthesis of (R)-2-isopropyl-5-methylhex-5-enal in 98% ee is described. It was discovered that the key alkylation step employing an Evans chiral auxiliary and 3-methylbut-3-en-1-yl trifluoromethanesulphonate as the alkylating agent led to significant competing O-alkylation, a phenomenon not previously reported. Type II carbonyl ene cyclisation of the aldehyde with a range of Lewis acids led to either the (R,R)- or (R,S)-5-methylidenecyclohexanols without concurrent racemisation of the alpha stereogenic centre of the aldehyde. Conditions for effecting the easy racemisation of a model enantiomerically pure aldehyde, (S)-2-methylbutanal, were developed. In an effort to secure a dynamic kinetic resolution procedure, these conditions were applied to (R)-2-isopropyl-5-methylhex-5-enal. However, a competing and dominant Prins cyclisation occurred instead leading to a mixture of all possible cycloadducts, all of which were obtained in 98% ee. Any unreacted aldehyde was found to be enantiomerically pure. (C) 2000 Elsevier Science Ltd. All rights reserved.

  DOI：

  10.1016/s0957-4166(00)00316-5
• 作为产物：
  描述：

  (4R,5S)-(+)-3-[(2R)-2-isopropyl-5-methyl-1-oxohex-5-en-1-yl]-4-methyl-5-phenyl-2-oxazolidinone 在 lithium hydroxide 、 双氧水 作用下， 以 四氢呋喃 、 水 为溶剂， 反应 16.0h， 以75%的产率得到(R)-(+)-2-isopropyl-5-methylhex-5-ene-1-carboxylic acid
  参考文献：
  名称：

  Asymmetric synthesis and Lewis acid mediated type II carbonyl ene cyclisations of (R)-2-isopropyl-5-methylhex-5-enal

  摘要：

  The asymmetric synthesis of (R)-2-isopropyl-5-methylhex-5-enal in 98% ee is described. It was discovered that the key alkylation step employing an Evans chiral auxiliary and 3-methylbut-3-en-1-yl trifluoromethanesulphonate as the alkylating agent led to significant competing O-alkylation, a phenomenon not previously reported. Type II carbonyl ene cyclisation of the aldehyde with a range of Lewis acids led to either the (R,R)- or (R,S)-5-methylidenecyclohexanols without concurrent racemisation of the alpha stereogenic centre of the aldehyde. Conditions for effecting the easy racemisation of a model enantiomerically pure aldehyde, (S)-2-methylbutanal, were developed. In an effort to secure a dynamic kinetic resolution procedure, these conditions were applied to (R)-2-isopropyl-5-methylhex-5-enal. However, a competing and dominant Prins cyclisation occurred instead leading to a mixture of all possible cycloadducts, all of which were obtained in 98% ee. Any unreacted aldehyde was found to be enantiomerically pure. (C) 2000 Elsevier Science Ltd. All rights reserved.

  DOI：

  10.1016/s0957-4166(00)00316-5

文献信息

• Asymmetric synthesis and Lewis acid mediated type II carbonyl ene cyclisations of (R)-2-isopropyl-5-methylhex-5-enal
  作者：D.Christopher Braddock、John M Brown

  DOI：10.1016/s0957-4166(00)00316-5

  日期：2000.9

  The asymmetric synthesis of (R)-2-isopropyl-5-methylhex-5-enal in 98% ee is described. It was discovered that the key alkylation step employing an Evans chiral auxiliary and 3-methylbut-3-en-1-yl trifluoromethanesulphonate as the alkylating agent led to significant competing O-alkylation, a phenomenon not previously reported. Type II carbonyl ene cyclisation of the aldehyde with a range of Lewis acids led to either the (R,R)- or (R,S)-5-methylidenecyclohexanols without concurrent racemisation of the alpha stereogenic centre of the aldehyde. Conditions for effecting the easy racemisation of a model enantiomerically pure aldehyde, (S)-2-methylbutanal, were developed. In an effort to secure a dynamic kinetic resolution procedure, these conditions were applied to (R)-2-isopropyl-5-methylhex-5-enal. However, a competing and dominant Prins cyclisation occurred instead leading to a mixture of all possible cycloadducts, all of which were obtained in 98% ee. Any unreacted aldehyde was found to be enantiomerically pure. (C) 2000 Elsevier Science Ltd. All rights reserved.