3-(4-bromophenyl)-5-(1-hydroxyethyl)-1,2,4-oxadiazole | 1196958-30-1

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 唑类
• 英文名称: 3-(4-bromophenyl)-5-(1-hydroxyethyl)-1,2,4-oxadiazole
• 英文别名: 1-[3-(4-bromophenyl)-1,2,4-oxadiazol-5-yl]ethanol
• CAS: 1196958-30-1
• 化学式: C₁₀H₉BrN₂O₂
• 分子量: 269.098
• InChiKey: IQKUUYCXYHTFQR-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2
• 重原子数：
  15
• 可旋转键数：
  2
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.2
• 拓扑面积：
  59.2
• 氢给体数：
  1
• 氢受体数：
  4

反应信息

• 作为反应物：
  描述：

  乙酸-4-氯苯酯 、 3-(4-bromophenyl)-5-(1-hydroxyethyl)-1,2,4-oxadiazole 在 1-hydroxytetraphenylcyclopentadienyl(tetraphenyl-2,4-cyclopentadien-1-one)-μ-hydrotetracarbonyldiruthenium(II) 作用下， 以 甲苯 为溶剂， 反应 48.0h， 以47%的产率得到(1R)-1-[3-(4-bromophenyl)-1,2,4-oxadiazol-5-yl]ethyl acetate
  参考文献：
  名称：

  Efficient Chemoenzymatic Dynamic Kinetic Resolution of 1-Heteroaryl Ethanols

  摘要：

  The scope and limitation of the combined rutheinum-lipase induced dynamic kinetic resolution (DKR) through O-acetylation of racemic heteroaromatic secondary alcohols, i.e., 1-heteroaryl substituted ethanols, was investigated. After initial screening of reaction conditions, Candida antarctica lipase B (Novozyme 435, N435) together with 4-chloro-phenylacetate as acetyl-donor for kinetic resolution (KR), in conjunction with the ruthenium-based Shvo catalyst for substrate racemization in toluene at 80 degrees C, enabled DKR with high yields and stereoselectivity of various 1-heteroaryl ethanols, Such as oxadiazoles, isoxazoles, 1H-pyrazole, or 1H-imidazole. In addition, DFT calculations based on a simplified catalyst complex model for the catalytic (de)hydrogenation step are in agreement with the previously reported outer sphere mechanism. These results support the further understanding of the mechanistic aspects behind the difference in reactivity of 1-heteroaryl substituted ethanols in comparison to reference substrates, as often referred to in the literature.

  DOI：

  10.1021/jo901987z
• 作为产物：
  描述：

  1-[3-(4-bromophenyl)-1,2,4-oxadiazol-5-yl]ethanone 在 sodium tetrahydroborate 作用下， 以 四氢呋喃 为溶剂， 反应 16.0h， 以10%的产率得到3-(4-bromophenyl)-5-(1-hydroxyethyl)-1,2,4-oxadiazole
  参考文献：
  名称：

  Efficient Chemoenzymatic Dynamic Kinetic Resolution of 1-Heteroaryl Ethanols

  摘要：

  The scope and limitation of the combined rutheinum-lipase induced dynamic kinetic resolution (DKR) through O-acetylation of racemic heteroaromatic secondary alcohols, i.e., 1-heteroaryl substituted ethanols, was investigated. After initial screening of reaction conditions, Candida antarctica lipase B (Novozyme 435, N435) together with 4-chloro-phenylacetate as acetyl-donor for kinetic resolution (KR), in conjunction with the ruthenium-based Shvo catalyst for substrate racemization in toluene at 80 degrees C, enabled DKR with high yields and stereoselectivity of various 1-heteroaryl ethanols, Such as oxadiazoles, isoxazoles, 1H-pyrazole, or 1H-imidazole. In addition, DFT calculations based on a simplified catalyst complex model for the catalytic (de)hydrogenation step are in agreement with the previously reported outer sphere mechanism. These results support the further understanding of the mechanistic aspects behind the difference in reactivity of 1-heteroaryl substituted ethanols in comparison to reference substrates, as often referred to in the literature.

  DOI：

  10.1021/jo901987z

文献信息

• One-Step Protection-Free Synthesis of 3-Aryl-5-hydroxyalkyl-1,2,4-oxadiazoles as Building Blocks
  作者：Ricardo A. W. Neves Filho、Diana C. B. da Silva-Alves、Janaína V. dos Anjos、Rajendra M. Srivastava

  DOI：10.1080/00397911.2012.724757

  日期：2013.10.2

  A simple and straightforward synthesis of 3-aryl-5-hydroxyalkyl-1,2,4-oxadiazoles is described. The reaction among arylamidoximes, ethyl glycolate or ethyl lactate, and potassium carbonate in refluxing toluene afforded the desired 1,2,4-oxadiazoles in moderate to good yields. The synthesis has been accomplished in a single step, avoiding protection-deprotection protocols. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications (R) to view the free supplemental file.
• Efficient Chemoenzymatic Dynamic Kinetic Resolution of 1-Heteroaryl Ethanols
  作者：Karl S. A. Vallin、David Wensbo Posaric、Zdenko Hameršak、Mats A. Svensson、Alexander B. E. Minidis

  DOI：10.1021/jo901987z

  日期：2009.12.18

  The scope and limitation of the combined rutheinum-lipase induced dynamic kinetic resolution (DKR) through O-acetylation of racemic heteroaromatic secondary alcohols, i.e., 1-heteroaryl substituted ethanols, was investigated. After initial screening of reaction conditions, Candida antarctica lipase B (Novozyme 435, N435) together with 4-chloro-phenylacetate as acetyl-donor for kinetic resolution (KR), in conjunction with the ruthenium-based Shvo catalyst for substrate racemization in toluene at 80 degrees C, enabled DKR with high yields and stereoselectivity of various 1-heteroaryl ethanols, Such as oxadiazoles, isoxazoles, 1H-pyrazole, or 1H-imidazole. In addition, DFT calculations based on a simplified catalyst complex model for the catalytic (de)hydrogenation step are in agreement with the previously reported outer sphere mechanism. These results support the further understanding of the mechanistic aspects behind the difference in reactivity of 1-heteroaryl substituted ethanols in comparison to reference substrates, as often referred to in the literature.