(+/-)-2-Isopropyl-5-methylhex-5-enal | 97690-19-2

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: (+/-)-2-Isopropyl-5-methylhex-5-enal
• 英文别名: 5-Methyl-2-propan-2-ylhex-5-enal
• CAS: 97690-19-2
• 化学式: C₁₀H₁₈O
• 分子量: 154.252
• InChiKey: KQHKCWXITYVPCH-UHFFFAOYSA-N

物化性质

• 沸点：
  201.0±19.0 °C(Predicted)
• 密度：
  0.826±0.06 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  3.1
• 重原子数：
  11
• 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：
  17.1
• 氢给体数：
  0
• 氢受体数：
  1

反应信息

• 作为反应物：
  描述：

  (+/-)-2-Isopropyl-5-methylhex-5-enal 在 六甲基磷酰三胺 、 lithium diisopropyl amide 作用下， 以 四氢呋喃 为溶剂， 反应 1.0h， 生成 6-isopropyl-9-methylbicyclo<4.3.0>nonan-3-one
  参考文献：
  名称：

  Intramolecular routes to hydrindanes: the Diels-Alder and Michael aldol approach to 6-isopropyl-9-methylbicyclo[4.3.0]nonan-3-one

  摘要：

  DOI：

  10.1021/jo00218a038
• 作为产物：
  描述：

  4-碘-2-甲基丁-1-烯 在 溶剂黄146 、 lithium diisopropyl amide 作用下， 以 四氢呋喃 、 正己烷 为溶剂， 反应 2.0h， 生成 (+/-)-2-Isopropyl-5-methylhex-5-enal
  参考文献：
  名称：

  Catalytic and Stoichiometric Lewis Acid Participation in Aldehyde Ene Cyclisations

  摘要：

  为了探索导致薄荷醇类似物的烯丙基化反应，合成了外消旋2-异丙基-2-甲基己-5-烯醛。首要目标是发现有利于烯丙基化生成薄荷醇而非新薄荷醇系列的催化条件，然后开发（动态）动力学分辨程序，以获得产品的单对映体。发现催化量的Me2AlCl和体积庞大的甲基铝双（酚氧基）试剂可产生与Meerwein-Pondorff-Verley反应相关的产物。在此反应中，醛被还原为初级醇，烯基产物被氧化为相应的α，β-不饱和酮。相比之下，相关的体积庞大氯化铝试剂催化的烯丙基化反应干净地进行，但更倾向于不受欢迎的新薄荷醇立体异构体。

  DOI：

  10.1135/cccc20000741

文献信息

• Unprecedented stereochemical control in the intramolecular ene-reactions of δ,ε-unsaturated aldehydes using exceptionally bulky organoaluminum reagents: Elucidation of the transition state
  作者：Takashi Ooi、Keiji Maruoka、Hisashi Yamamoto

  DOI：10.1016/s0040-4020(01)89682-4

  日期：——

  Unprecedented stereochemical control has been achieved in the type II intramolecular ene reactions of δ,ε-unsaturated aldehydes leading to trans-cyclohexanols with excellent selectivity under very mild conditions, using exceptionally bulky methylaluminum bis(4-bromo-2,6-di-tert-butylphenoxide) (MABR). Success of the stereocontrolled cyclization can be ascribable to the ability of this modified organoaluminum

  前所未有的立体化学控制已在类型已经实现δ，ε不饱和醛导致的II分子内烯反应反式使用极其巨大，甲基铝双非常温和的条件下具有优良的选择性-cyclohexanols，（4-溴-2,6-二-叔-丁基苯氧化物）（MABR）。立体控制环化的成功可以归因于这种改性的有机铝试剂MABR改变过渡态构象的能力。检查基板的烯反应7，11，14与MABR，本有机铝助分子内烯反应的立体化学结果被进一步阐明。
• Models for the Carbonyl-ene Cyclization Reaction: Open and Closed Transition States
  作者：D. Christopher Braddock、King Kuok (Mimi) Hii、John M. Brown

  DOI：10.1002/(sici)1521-3773(19980703)37:12<1720::aid-anie1720>3.0.co;2-w

  日期：1998.7.3

  Different cyclization products are formed with different Lewis acids in the ene cyclization of 5-hexenals (see scheme on the right; a: methylaluminum bisphenoxide, b: Me2 AlCl, c: Sc(OSO2 CF3 )3 ). This is not surprising, but it is gratifying that these result can be rationalized with an internally consistent model.
• 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.
• MARUOKA, KEIJI;OOI, TAKASHI;YAMAMOTO, HISASHI, J. AMER. CHEM. SOC., 112,(1990) N4, C. 9011-9012
  作者：MARUOKA, KEIJI、OOI, TAKASHI、YAMAMOTO, HISASHI

  DOI：——

  日期：——
• Catalytic and Stoichiometric Lewis Acid Participation in Aldehyde Ene Cyclisations
  作者：D. Christopher Braddock、John M. Brown

  DOI：10.1135/cccc20000741

  日期：——

  Racemic 2-isopropyl-2-methylhex-5-enal has been synthesised in order to probe ene cyclisations leading to menthol analogues. The objective was first to discover catalytic conditions for preferential cyclisation to the menthol rather than the neomenthol series and then to develop (dynamic) kinetic resolution procedures which afforded a single enantiomer of product. It was found that catalytic quantities of both Me₂AlCl and a bulky methylaluminium bis(phenoxide) reagent gave products attributed to a Meerwein-Pondorff-Verley reaction. In this the aldehyde is reduced to a primary alcohol and the ene product oxidised to the corresponding α,β-unsaturated ketone. By contrast, a related bulky chloroaluminium reagent catalysed the ene cyclisation cleanly, but preferentially to the undesired neomenthyl stereoisomer.

  为了探索导致薄荷醇类似物的烯丙基化反应，合成了外消旋2-异丙基-2-甲基己-5-烯醛。首要目标是发现有利于烯丙基化生成薄荷醇而非新薄荷醇系列的催化条件，然后开发（动态）动力学分辨程序，以获得产品的单对映体。发现催化量的Me2AlCl和体积庞大的甲基铝双（酚氧基）试剂可产生与Meerwein-Pondorff-Verley反应相关的产物。在此反应中，醛被还原为初级醇，烯基产物被氧化为相应的α，β-不饱和酮。相比之下，相关的体积庞大氯化铝试剂催化的烯丙基化反应干净地进行，但更倾向于不受欢迎的新薄荷醇立体异构体。