Reller Malin, Wesp Svenja, Koos Martin R M, Reggelin Michael, Luy Burkhard
Institut für Organische Chemie and Institut für Biologische Grenzflächen 4 - Magnetische Resonanz, Karlsruher Institut für Technologie (KIT), Fritz-Haber-Weg 6, 76131, Karlsruhe, Germany.
Organische Chemie, Technische Universität Darmstadt, Alarich-Weiss Str. 4, 64287, Darmstadt, Germany.
Chemistry. 2017 Sep 27;23(54):13351-13359. doi: 10.1002/chem.201702126. Epub 2017 Jul 26.
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.
当传统技术不足以解决问题时，剩余偶极耦合和其他各向异性核磁共振参数是阐明分子结构的有力工具。使用当前的液晶制剂时，需要制备两个样品，以便从光谱中提取各向同性和各向异性数据，并推导剩余偶极耦合。在此，我们展示了一种新型双相液晶相的制备、测量和解释，其中单个样品可用于生成各向同性和各向异性数据。首先，我们介绍了导致双相液晶的手性聚合物的合成。其次，我们展示了两种测量空间选择性CLIP-HSQC光谱的方法。从这些光谱中，我们提取了耦合，对非对映体质子进行了归属，并实现了对作为充分研究的测试分子的异松蒎醇的对映体鉴别。
