Solid State and Structural Chemistry Unit, Bangalore 560 012, India.
J Magn Reson. 2010 Dec;207(2):190-6. doi: 10.1016/j.jmr.2010.08.021. Epub 2010 Sep 26.
We report a single (13)C spin edited selective proton-proton correlation experiment to decipher overcrowded (13)C coupled proton NMR spectra of weakly dipolar coupled spin systems. The experiment unravels the masked (13)C satellites in proton spectrum and permits the measurement of one bond carbon-proton residual dipolar couplings in I(3)S and for each diastereotopic proton in I(2)S groups. It also provides all the possible homonuclear proton-proton residual couplings which are otherwise difficult to extract from the broad and featureless one dimensional (1)H spectrum, in addition to enantiodifferentiation in a chiral molecule. Employment of heteronuclear ((13)C) decoupling in the evolution period results in complete demixing of overlapped signals from enantiomers. The observed anomalous intensity pattern in strongly dipolar coupled methyl protons in methyl selective correlation experiment has been interpreted using polarization operator formalism.
我们报告了一种单（13）C 自旋编辑选择性质子-质子相关实验，以破译弱偶极耦合自旋系统中拥挤的（13）C 耦合质子 NMR 谱。该实验揭示了质子谱中被掩盖的（13）C 卫星，并允许测量 I(3)S 中一价碳-质子残偶极耦合，以及 I(2)S 基团中每个非对映质子的残偶极耦合。此外，它还提供了所有可能的同核质子-质子残偶耦合，否则很难从宽且无特征的一维（1）H 谱中提取，除了手性分子中的对映体区分。在演化期使用异核（13）C 去耦可导致对映体重叠信号完全分离。在甲基选择性相关实验中，强偶极耦合甲基质子中观察到的异常强度模式已使用极化算子形式理论进行了解释。
