Biphasic Liquid Crystal and the Simultaneous Measurement of Isotropic and Anisotropic Parameters by Spatially Resolved NMR Spectroscopy.
Malin RellerSvenja WespMartin R M KoosMichael ReggelinBurkhard LuyPublished in: Chemistry (Weinheim an der Bergstrasse, Germany) (2017)
Residual dipolar couplings and other anisotropic NMR parameters are powerful tools for molecular structure elucidation when conventional techniques do not suffice. With current liquid crystalline preparations it is necessary to prepare two samples to extract isotropic and anisotropic data from spectra and to derive the residual dipolar couplings. Here, we present the preparation, measurement, and interpretation of a novel biphasic liquid crystalline phase where a single sample can be used to generate both isotropic and anisotropic data. First, we introduce the synthesis of the chiral polymer leading to the biphasic liquid crystal. Second, we present two approaches to measure spatially selective CLIP-HSQC spectra. From these spectra, we extracted the couplings, performed an assignment of diastereotopic protons, and achieved the enantiomeric discrimination of isopinocampheol as a well-studied test molecule.