Abstract

¹³C NMR spectroscopic analyses of C_s symmetric guest molecules in the cyclodextrin host cavity, combined with molecular modelling and solid-state X-ray analysis, provides a detailed description of the spatial arrangement of cyclodextrin host–guest complexes in solution. The chiral cavity of the cyclodextrin molecule creates an anisotropic environment for the guest molecule resulting in a splitting of its prochiral carbon signals in ¹³C NMR spectra. This signal split can be correlated to the distance of the guest atoms from the wall of the host cavity and to the spatial separation of binding sites preferred by pairs of prochiral carbon atoms. These measurements complement traditional solid-state analyses, which rely on the crystallization of host–guest complexes and their crystallographic analysis.

Beilstein J. Org. Chem. 2024, 20, 331–335. doi:10.3762/bjoc.20.33

摘要

对环糊精主腔中的C _s^{对称客体分子进行13} C NMR 光谱分析，结合分子建模和固态 X 射线分析，详细描述了溶液中环糊精主客体复合物的空间排列。环糊精分子的手性空腔为客体分子创造了各向异性环境，导致其前手性碳信号在¹³ C NMR 谱中分裂。这种信号分裂可以与客体原子距主体腔壁的距离以及前手性碳原子对优选的结合位点的空间间隔相关。这些测量补充了传统的固态分析，传统的固态分析依赖于主客体复合物的结晶及其晶体学分析。

贝尔斯坦 J. 组织。化学。 2024, 20, 331–335。 doi:10.3762/bjoc.20.33