The effect of a chiral nematic solvent on the orientational order and conformational distribution of a flexible prochiral solute
Résumé
Deuterium NMR spectroscopy is used to detect the reduction in symmetry which occurs when a flexible, prochiral molecule, 4-pentyl-4’-cyanobiphenyl, is dissolved in a chiral nematic solvent produced by dissolving poly-γ-benzyl-L-glutamate in organic solvents. The quadrupolar splittings obtained are used to investigate whether this phenomenon is the result of a reduction in symmetry of the anisotropic, solute-solvent potential or whether the conformational distribution is also affected. It is demonstrated that the first assumption explains the enantiotopic discrimination in chiral liquid crystals and it is possible in this chiral medium to determine the relative configuration of the deuteriums in the methylene groups.