Through-Bond 13 C− 13 C Correlation at the Natural Abundance Level: Refining Dynamic Regions in the Crystal Structure of Vitamin-D 3 with Solid-State NMR
2003; American Chemical Society; Volume: 125; Issue: 39 Linguagem: Inglês
10.1021/ja036655s
ISSN1943-2984
AutoresRyan A. Olsen, Jochem Struppe, Douglas W. Elliott, Richard J. Thomas, Leonard J. Mueller,
Tópico(s)Atomic and Subatomic Physics Research
ResumoRecently, we presented a novel nuclear magnetic resonance experiment for establishing through-bond connectivity in disordered solids using scalar coupling-driven correlation. This method, a variant of the popular double-quantum-filtered correlation spectroscopy experiment in liquids, is robust under fast magic-angle-spinning conditions and in the presence of dynamics. Here, we show that this new experiment, the UC2QF COSY, can be extended to 13C natural abundance correlation in moderately sized molecules, allowing the assignment of the 54 peaks of the solid-state NMR spectrum of microcrystalline vitamin-D3. In this case, comparison between the assigned peaks and ab initio calculations of the chemical shifts based on the crystal coordinates permits a refinement of the average structure in dynamic regions reported as disordered in the crystal structure.
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