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.

Lyotropic liquid crystalline (LLC) phases of amino acid derived polyarylisocyanides were employed as chiral alignment media for the measurement of residual dipolar couplings (RDCs) of small chiral organic molecules. Anisotropic samples in CDCl3 displayed quadrupolar splittings of the deuterium signal in the range of several hundreds of Hertz. The LLC phases showed excellent orienting properties for a broad range of analytes bearing various functional groups. The precise extraction of RDCs in the range of up to ±40 Hertz from F2‐coupled HSQC spectra was possible. Additionally, the chiral environment offers the opportunity for diastereomorphous interactions with the enantiomers of chiral analytes leading to two different sets of RDCs. This differential order effect was particularly pronounced with ketones and alcohols.

A moderately concentrated solution of a helically chiral polyisonitrile forms a stable two‐phase system in CDCl3 with the dense phase being close to isotropic and the less dense layer forming a completely anisotropic lyotropic liquid crystalline phase. This enables the enantiodifferentiating measurement of isotropic and anisotropic NMR parameters from a single sample by novel spatially resolved NMR methods. More information can be found in the Full Paper by M. Reggelin, B. Luy et al. on page 13351.

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