大学化学 >> 2022, Vol. 37 >> Issue (2): 2109027.doi: 10.3866/PKU.DXHX202109027

所属专题: 化学实验教学和管理

化学实验 上一篇    下一篇

核磁共振技术测定联萘酚的对映体纯度

奚忠华(), 陆大东, 戴洁, 叶涛, 章文伟   

  • 收稿日期:2021-09-10 录用日期:2021-09-13 发布日期:2021-11-05
  • 通讯作者: 奚忠华 E-mail:xizh@nju.edu.cn
  • 作者简介:奚忠华, Email: xizh@nju.edu.cn
  • 基金资助:
    2021年基础学科拔尖学生培养计划2.0课题

Determination of Enantiomeric Purity of Binaphthol by NMR Method

Zhonghua Xi(), Dadong Lu, Jie Dai, Tao Ye, Wenwei Zhang   

  • Received:2021-09-10 Accepted:2021-09-13 Published:2021-11-05
  • Contact: Zhonghua Xi E-mail:xizh@nju.edu.cn

摘要:

手性联萘酚((±)-BINOL)制备是国内高校常开设的一个实验,其产品的对映体纯度测试是实验的重要一环。以2-甲酰基苯硼酸和(S)-(-)-1-苯乙胺的混合物作为手性试剂与联萘酚发生Bull-James Assembly反应,以此设计了核磁共振氢谱(1H NMR)测定联萘酚对映体纯度的实验。实验结果表明,通过反应生成的对映体混合物的核磁信号,能准确地计算出(±)-BINOL的对映体纯度。以选定的苯环氢核信号计算出的(R)-BINOL含量与理论ee值有着良好的线性关系(R2=0.9999)。此实验方法能够快速完成大量学生样品的测量,同时大大减少实验废液的产生量。学生通过此实验可对核磁共振技术有更进一步的了解。

关键词: 核磁共振, 联萘酚, 对映体纯度, 对映体过量

Abstract:

The preparation of chiral binaphthol is a common experiment in colleges and universities, and the determination of enantiomeric purity is an important part of the experiment. The Bull-James Assembly between binaphthol and a mixture of 2-formylphenylboronic acid and (S)-(-)-1-phenylethylamine as chiral reagent was observed. Based on this, an experiment was designed to determine the enantiomer purity of binaphthol via 1H NMR. The results show that the enantiomer purity of (±)-BINOL can be accurately calculated from the NMR signals of the enantiomer mixture generated by the reaction. There is a good linear relationship (R2=0.9999) between the (R)-BINOL ratio calculated from the selected proton signal and the given ee value. This method can quickly complete the measurement of a large number of student samples, and produce a small amount of waste liquid. Students can have a further understanding of NMR technology through this experiment.

Key words: Nuclear magnetic resonance (NMR), Binaphthol (BINOL), Enantiomeric purity, Enantiomeric excess

MSC2000: 

  • G64