4-sec-butyl-5-methoxy-2-methyl-1,3-oxazole | 647012-95-1

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 唑类
• 英文名称: 4-sec-butyl-5-methoxy-2-methyl-1,3-oxazole
• 英文别名: 4-[(2S)-Butan-2-yl]-5-methoxy-2-methyl-1,3-oxazole；4-[(2S)-butan-2-yl]-5-methoxy-2-methyl-1,3-oxazole
• CAS: 647012-95-1
• 化学式: C₉H₁₅NO₂
• 分子量: 169.224
• InChiKey: UOOZEQZPICCGCJ-LURJTMIESA-N

物化性质

• 沸点：
  229.2±28.0 °C(Predicted)
• 密度：
  0.982±0.06 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  2.6
• 重原子数：
  12
• 可旋转键数：
  3
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.67
• 拓扑面积：
  35.3
• 氢给体数：
  0
• 氢受体数：
  3

反应信息

• 作为反应物：
  描述：

  4-sec-butyl-5-methoxy-2-methyl-1,3-oxazole 在 盐酸 作用下， 以 二氯甲烷 、 苯 为溶剂， 反应 24.0h， 生成
  参考文献：
  名称：

  5-甲氧基恶唑的光醛醇反应：α-氨基β-羟基羧酸衍生物的高度区域选择性和非对映选择性合成

  摘要：

  描述了具有叔（来自相应的甘氨酸等价物）或季 α-碳中心的 α-氨基 β-羟基羧酸衍生物的通用途径。关键反应是电子激发的羰基化合物（分别为芳香醛和脂肪醛）与恶唑的环加成反应。为了使产物水解更不稳定，在 C-5 位引入了甲氧基取代基，导致形成具有原酸酯亚结构的环加合物。光环加成，无论是三线态激发（芳香族）羰基化合物还是单线态激发（脂肪族）羰基化合物，都导致形成具有中等至极高外选择性的内型和外型非对映异构体的混合物。4-未取代的5-甲氧基恶唑1（甘氨酸等价物）以高产率和优异的非对映选择性得到[2+2]-加合物3a-β3f与醛2a-β2f。这些化合物的水解产生具有优选赤型 (S*,S*) 构型的 α-氨基 β-羟基酯 4a??4f...

  DOI：

  10.1139/v03-029
• 作为产物：
  描述：

  L-异亮氨酸 在 氯化亚砜 、 五氯化磷 、 三乙胺 作用下， 以 氯仿 为溶剂， 反应 4.0h， 生成 4-sec-butyl-5-methoxy-2-methyl-1,3-oxazole
  参考文献：
  名称：

  Synthesis of erythro-α-Amino β-hydroxy Carboxylic Acid Esters by Diastereoselective Photocycloaddition of 5-Methoxyoxazoles with Aldehydes

  摘要：

  A new photoaldol route to alpha-amino-beta-hydroxy carboxylic acid esters is initiated by the photocycloaddition of aromatic or aliphatic aldehydes to 5-methoxyoxazoles. The 4-unsubstituted 5-methyloxazole 1 gave the cycloadducts 8a-f in high yields and excellent exo-diastereoselectivities. Hydrolysis of 8a-f gives the N-acetyl alpha-amino-beta-hydroxy esters 9a-f, which could be subsequently converted into the corresponding Z-didehydro alpha-amino acids 10a-f. Quartenary alpha-amino-beta-hydroxy esters 12, 14, 16, 18, and 20, which are stable against dehydration, were obtained from the 4-alkylated 5-methoxyoxazoles 2-6, in most cases highly erythro-selective due to the high degree of stereocontrol (exo) at the photocycloaddition (to give 11, 13, 15, 17, and 19) level. The relative configurations of the N-acetyl alpha-amino-beta-hydroxy esters were determined by NMR spectroscopy and comparison with chiral pool-derived compounds as well as by X-ray structure determination of the ester 23, formed by hydrolysis of the cycloadduct 22, derived from photocycloaddition of propionaldehyde to the isoleucine-derived oxazole 21.

  DOI：

  10.1021/jo034830h

文献信息

• Synthesis of <i>e</i><i>rythro</i>-α-Amino β-hydroxy Carboxylic Acid Esters by Diastereoselective Photocycloaddition of 5-Methoxyoxazoles with Aldehydes
  作者：Axel G. Griesbeck、Samir Bondock、Johann Lex

  DOI：10.1021/jo034830h

  日期：2003.12.1

  A new photoaldol route to alpha-amino-beta-hydroxy carboxylic acid esters is initiated by the photocycloaddition of aromatic or aliphatic aldehydes to 5-methoxyoxazoles. The 4-unsubstituted 5-methyloxazole 1 gave the cycloadducts 8a-f in high yields and excellent exo-diastereoselectivities. Hydrolysis of 8a-f gives the N-acetyl alpha-amino-beta-hydroxy esters 9a-f, which could be subsequently converted into the corresponding Z-didehydro alpha-amino acids 10a-f. Quartenary alpha-amino-beta-hydroxy esters 12, 14, 16, 18, and 20, which are stable against dehydration, were obtained from the 4-alkylated 5-methoxyoxazoles 2-6, in most cases highly erythro-selective due to the high degree of stereocontrol (exo) at the photocycloaddition (to give 11, 13, 15, 17, and 19) level. The relative configurations of the N-acetyl alpha-amino-beta-hydroxy esters were determined by NMR spectroscopy and comparison with chiral pool-derived compounds as well as by X-ray structure determination of the ester 23, formed by hydrolysis of the cycloadduct 22, derived from photocycloaddition of propionaldehyde to the isoleucine-derived oxazole 21.
• Photo aldol reactions with 5-methoxyoxazoles: Highly regio- and diastereoselective synthesis of α-amino β-hydroxy carboxylic acid derivatives
  作者：Axel G Griesbeck、Samir Bondock

  DOI：10.1139/v03-029

  日期：2003.6.1

  A versatile route to derivatives of α-amino β-hydroxy carboxylic acids, either with tertiary (from a corresponding glycine equivalent) or a quaternary α-carbon center is described. The key reaction is the cycloaddition of electronically excited carbonyl compounds (aromatic and aliphatic aldehydes, respectively) to oxazoles. To make the products hydrolytically more labile, a methoxy substituent at position

  描述了具有叔（来自相应的甘氨酸等价物）或季 α-碳中心的 α-氨基 β-羟基羧酸衍生物的通用途径。关键反应是电子激发的羰基化合物（分别为芳香醛和脂肪醛）与恶唑的环加成反应。为了使产物水解更不稳定，在 C-5 位引入了甲氧基取代基，导致形成具有原酸酯亚结构的环加合物。光环加成，无论是三线态激发（芳香族）羰基化合物还是单线态激发（脂肪族）羰基化合物，都导致形成具有中等至极高外选择性的内型和外型非对映异构体的混合物。4-未取代的5-甲氧基恶唑1（甘氨酸等价物）以高产率和优异的非对映选择性得到[2+2]-加合物3a-β3f与醛2a-β2f。这些化合物的水解产生具有优选赤型 (S*,S*) 构型的 α-氨基 β-羟基酯 4a??4f...