Two-Dimensional Deuterium NMR Spectroscopy of Chiral Molecules Oriented in a Polypeptide Liquid Crystal: Applications for the Enantiomeric Analysis through Natural Abundance Deuterium NMR
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- 作者：Denis Merlet ; Bernard Ancian ; Jacques Courtieu ; and Philippe Lesot
- 刊名：Journal of the American Chemical Society
- 出版年：1999
- 出版时间：June 9, 1999
- 年：1999
- 卷：121
- 期：22
- 页码：5249 - 5258
- 全文大小：106K
- 年卷期：v.121,no.22(June 9, 1999)
- ISSN：1520-5126
文摘
We describe several two-dimensional NMR experiments to facilitate the analysis of overcrowdedproton-decoupled deuterium spectra of chiral molecules oriented in poly-
-benzyl-L-glutamate liquid crystallinesolutions. These 2D NMR experiments allow the correlation between the components of each quadrupolardoublet in the deuterium spectra and then their assignment on the basis of chemical shift. The 2D pulse sequencesproposed in this work were developed using the Cartesian spin-operator formalism for spin I = 1 nuclei witha small quadrupolar moment, such as deuterons in high magnetic field. The features and analytical potentialitiesof each pulse sequence are discussed and compared. Illustrative applications of these sequences in naturalabundance deuterium NMR spectroscopy using a 9.4 T magnetic field and standard NMR equipment are reportedand examined. With this technique, it is demonstrated that quantitative measurements are possible within aprecision of 10%.
-benzyl-L-glutamate liquid crystallinesolutions. These 2D NMR experiments allow the correlation between the components of each quadrupolardoublet in the deuterium spectra and then their assignment on the basis of chemical shift. The 2D pulse sequencesproposed in this work were developed using the Cartesian spin-operator formalism for spin I = 1 nuclei witha small quadrupolar moment, such as deuterons in high magnetic field. The features and analytical potentialitiesof each pulse sequence are discussed and compared. Illustrative applications of these sequences in naturalabundance deuterium NMR spectroscopy using a 9.4 T magnetic field and standard NMR equipment are reportedand examined. With this technique, it is demonstrated that quantitative measurements are possible within aprecision of 10%.