Moutzouri Pinelopi, Paruzzo Federico M, Simões de Almeida Bruno, Stevanato Gabriele, Emsley Lyndon
Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.
Angew Chem Int Ed Engl. 2020 Apr 6;59(15):6235-6238. doi: 10.1002/anie.201916335. Epub 2020 Feb 19.
The typical linewidths of H NMR spectra of powdered organic solids at 111 kHz magic-angle spinning (MAS) are of the order of a few hundred Hz. While this is remarkable in comparison to the tens of kHz observed in spectra of static samples, it is still the key limit to the use of H in solid-state NMR, especially for complex systems. Here, we demonstrate a novel strategy to further improve the spectral resolution. We show that the anti-z-COSY experiment can be used to reduce the residual line broadening of H NMR spectra of powdered organic solids. Results obtained with the anti-z-COSY sequence at 100 kHz MAS on thymol, β-AspAla, and strychnine show an improvement in resolution of up to a factor of two compared to conventional spectra acquired at the same spinning rate.
在111千赫兹魔角旋转（MAS）条件下，粉末状有机固体的¹H核磁共振谱的典型线宽约为几百赫兹。虽然与静态样品谱中观察到的几十千赫兹相比，这已经很显著了，但它仍然是固态核磁共振中¹H使用的关键限制，特别是对于复杂体系。在此，我们展示了一种进一步提高光谱分辨率的新策略。我们表明，反z-COSY实验可用于减少粉末状有机固体¹H核磁共振谱的残余线宽展宽。在百里酚、β-天冬氨酰丙氨酸和士的宁上，以100千赫兹MAS的反z-COSY序列获得的结果表明，与在相同旋转速率下采集的传统谱相比，分辨率提高了两倍。
