Enantiodiscrimination of Inherently Chiral Thiacalixarenes by Residual Dipolar Couplings

0568178 - ÚOCHB 2025 RIV US eng J - Journal Article
Tichotová, Markéta - Landovský, T. - Lang, J. - Jeziorowski, S. - Schmidts, V. - Kohout, M. - Babor, M. - Lhoták, P. - Thiele, C. M. - Dvořáková, H.
Enantiodiscrimination of Inherently Chiral Thiacalixarenes by Residual Dipolar Couplings.
Journal of Organic Chemistry. (2023). ISSN 0022-3263. E-ISSN 1520-6904
Institutional support: RVO:61388963
Keywords : polypeptide liquid crystals * deuterium NMR spectroscopy * alignment medium
OECD category: Organic chemistry
Impact factor: 3.6, year: 2022
Method of publishing: Open access
https://doi.org/10.1021/acs.joc.2c02594

Inherently chiral compounds, such as calixarenes, are chiral due to a nonplanar three-dimensional (3D) structure. Determining their conformation is essential to understand their properties, with nuclear magnetic resonance (NMR) spectroscopy being one applicable method. Using alignment media to measure residual dipolar couplings (RDCs) to obtain structural information is advantageous when classical NMR parameters like the nuclear Overhauser effect (NOE) or J-couplings fail. Besides providing more accurate structural information, the alignment media can induce different orientations of enantiomers. In this study, we examined the ability of polyglutamates with different side-chain moieties─poly-γ-benzyl-l-glutamate (PBLG) and poly-γ-p-biphenylmethyl-l-glutamate (PBPMLG) ─to enantiodifferentiate the inherently chiral phenoxathiin-based thiacalix[4]arenes. Both media, in combination with two solvents, allowed for enantiodiscrimination, which was, to the best of our knowledge, proved for the first time on inherently chiral compounds. Moreover, using the experimental RDCs, we investigated the calix[4]arenes conformational preferences in solution, quantitatively analyzed the differences in the alignment of the enantiomers, and discussed the pitfalls of the use of the RDC analysis.
Permanent Link: https://hdl.handle.net/11104/0339512


Research data: CCDC