NMR Research Centre, Indian Institute of Science, Bangalore, India.
J Magn Reson. 2010 Jan;202(1):34-7. doi: 10.1016/j.jmr.2009.09.020. Epub 2009 Sep 30.
One-dimensional (1D) proton NMR spectra of enantiomers are generally undecipherable in chiral orienting poly-gamma-benzyl-L-glutamate (PBLG)/CDCl(3) solvent. This arises due to large number of couplings, in addition to superposition of spectra from both the enantiomers, severely hindering the (1)H detection. On the other hand in the present study the benefit is derived from the presence of several couplings among the entire network of interacting protons. Transition selective 1D (1)H-(1)H correlation experiment (1D-COSY) which utilizes the coupling assisted transfer of magnetization not only for unraveling the overlap but also for the selective detection of enantiopure spectrum is reported. The experiment is simple, easy to implement and provides accurate eanantiomeric excess in addition to the determination of the proton-proton couplings of an enantiomer within a short experimental time (few minutes).
对映体的一维（1D）质子 NMR 光谱通常在手性导向聚-γ-苄基-L-谷氨酸酯（PBLG）/CDCl（3）溶剂中无法解读。这是由于除了两个对映体光谱的叠加之外，耦合数量很大，严重阻碍了（1）H 的检测。另一方面，在本研究中，整个相互作用质子网络中的几个耦合带来了好处。报道了一种利用耦合辅助磁化转移的过渡选择 1D（1）H-（1）H 相关实验（1D-COSY），该实验不仅可用于解开重叠，还可用于选择性检测对映纯光谱。该实验简单、易于实施，除了在短实验时间内（几分钟内）确定质子-质子耦合外，还可提供准确的对映过量值。
