(2R,4S)-4-[tert-butyl(dimethyl)silyl]oxy-N-[(1S,2S)-1-hydroxy-1-phenylpropan-2-yl]-N,2-dimethylpentanamide | 176198-62-2

• 分子结构分类: 有机化合物 - 苯类化合物 - 苯和取代衍生物
• 英文名称: (2R,4S)-4-[tert-butyl(dimethyl)silyl]oxy-N-[(1S,2S)-1-hydroxy-1-phenylpropan-2-yl]-N,2-dimethylpentanamide
• CAS: 176198-62-2
• 化学式: C₂₂H₃₉NO₃Si
• 分子量: 393.642
• InChiKey: XCJGDIKVAFPXKW-DOADOZAASA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5.0
• 重原子数：
  27
• 可旋转键数：
  9
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.68
• 拓扑面积：
  49.8
• 氢给体数：
  1
• 氢受体数：
  3

反应信息

• 作为反应物：
  描述：

  乙酸酐 、 (2R,4S)-4-[tert-butyl(dimethyl)silyl]oxy-N-[(1S,2S)-1-hydroxy-1-phenylpropan-2-yl]-N,2-dimethylpentanamide 在 4-二甲氨基吡啶 、 四丁基氟化铵 作用下， 生成 [(2R,4S)-5-[[(1S,2S)-1-acetyloxy-1-phenylpropan-2-yl]-methylamino]-4-methyl-5-oxopentan-2-yl] acetate
  参考文献：
  名称：

  Practical Syntheses of Enantiomerically Enriched γ-Lactones and γ-Hydroxy Ketones by the Alkylation of Pseudoephedrine Amides with Epoxides and Their Derivatives

  摘要：

  Pseudoephedrine amide enolates are shown to undergo efficient alkylation reactions with epoxides as electrophiles. Reactions with monosubstituted epoxides are subject to stereochemical matching such that the pairing leading to the 1,3-syn diastereomer is a highly selective, synthetically useful process, while the pairing forming the 1,3-anti diastereomer is not. Reactions with the 1,1-disubstituted epoxide isobutylene oxide are also highly diastereoselective and synthetically useful, but ethylene oxide exhibits poor diastereoselectivity. As an alternative to the use of ethylene oxide, 2-(tert-butyldimethylsilyloxy)ethyl iodide is shown to undergo highly diastereoselective and efficient alkylation reactions with pseudoephedrine amide enolates. Interestingly, epoxides and alkyl halides are found to attack opposite pi-faces of pseudoephedrine amide enolates. The products of each of these alkylation reactions are transformed efficiently into gamma-lactones by acidic hydrolysis and into methyl ketones by the addition of methyllithium. The methodology described provides useful procedures for the synthesis of enantiomerically enriched gamma-lactones and gamma-hydroxy ketones.

  DOI：

  10.1021/jo952032o
• 作为产物：
  描述：

  (S)-(+)-tert-Butyl(2-iodo-1-methylethoxy)dimethylsilane 、 (1S,2S)-(+)-伪麻黄碱丙酰胺 在 lithium chloride 、 lithium diisopropyl amide 作用下， 生成 (2R,4S)-4-[tert-butyl(dimethyl)silyl]oxy-N-[(1S,2S)-1-hydroxy-1-phenylpropan-2-yl]-N,2-dimethylpentanamide
  参考文献：
  名称：

  Practical Syntheses of Enantiomerically Enriched γ-Lactones and γ-Hydroxy Ketones by the Alkylation of Pseudoephedrine Amides with Epoxides and Their Derivatives

  摘要：

  Pseudoephedrine amide enolates are shown to undergo efficient alkylation reactions with epoxides as electrophiles. Reactions with monosubstituted epoxides are subject to stereochemical matching such that the pairing leading to the 1,3-syn diastereomer is a highly selective, synthetically useful process, while the pairing forming the 1,3-anti diastereomer is not. Reactions with the 1,1-disubstituted epoxide isobutylene oxide are also highly diastereoselective and synthetically useful, but ethylene oxide exhibits poor diastereoselectivity. As an alternative to the use of ethylene oxide, 2-(tert-butyldimethylsilyloxy)ethyl iodide is shown to undergo highly diastereoselective and efficient alkylation reactions with pseudoephedrine amide enolates. Interestingly, epoxides and alkyl halides are found to attack opposite pi-faces of pseudoephedrine amide enolates. The products of each of these alkylation reactions are transformed efficiently into gamma-lactones by acidic hydrolysis and into methyl ketones by the addition of methyllithium. The methodology described provides useful procedures for the synthesis of enantiomerically enriched gamma-lactones and gamma-hydroxy ketones.

  DOI：

  10.1021/jo952032o

文献信息

• Pseudoephedrine as a Practical Chiral Auxiliary for the Synthesis of Highly Enantiomerically Enriched Carboxylic Acids, Alcohols, Aldehydes, and Ketones
  作者：Andrew G. Myers、Bryant H. Yang、Hou Chen、Lydia McKinstry、David J. Kopecky、James L. Gleason

  DOI：10.1021/ja970402f

  日期：1997.7.1

  pseudoephedrine as a practical chiral auxiliary for asymmetric synthesis is described in full. Both enantiomers of pseudoephedrine are inexpensive commodity chemicals and can be N-acylated in high yields to form tertiary amides. In the presence of lithium chloride, the enolates of the corresponding pseudoephedrine amides undergo highly diastereoselective alkylations with a wide range of alkyl halides to

  伪麻黄碱作为不对称合成的实用手性助剂的使用进行了全面的描述。伪麻黄碱的两种对映异构体都是廉价的商品化学品，可以高产率进行 N-酰化以形成叔酰胺。在氯化锂的存在下，相应的伪麻黄碱酰胺的烯醇化物与多种卤代烷发生高度非对映选择性的烷基化反应，以高产率得到 α-取代产物。然后，这些产品可以在一次操作中转化为高度对映异构的羧酸、醇、醛和酮。