title: Molecular Mechanisms of Dielectrically Controlled Resolution (DCR).
abstract: It is widely believed that the chiral discrimination process is solely dependent on the stereochemistryof the relevant molecules. However, through systematic studies on several resolution systems with popularchiral selectors, we have discovered a new fact that triggers modification of this prevailing conceptof chiral resolution. The studies have demonstrated that one enantiomer of a chiral selector can recognizeboth enantiomers of a target molecule in different solvent systems with different dielectric constants.The phenomenon was termed dielectrically controlled resolution (DCR). Since DCR was observed in differentresolution systems and was not too specific to a particular system, DCR was expected to widely occurin various resolution systems. We have investigated the molecular mechanism underlying this interestingphenomenon based on X-ray analysis of the relevant diastereomeric salts. The disclosed mechanism clearlyindicates that a chiral selector can inherently recognize both enantiomers of a target moleculeand only the dielectric property of the solvent employed in the resolution process governs the selectionof the enantiomer.
authors.affiliation: R&D Division, Yamakawa Chemical Industry Co. Ltd., Kitaibaraki, 319-1541, Ibaraki, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Sakai
authors.forename: Rumiko
authors.initials: R
authors.lastname: Sakurai
authors.forename: Noriaki
authors.initials: N
authors.lastname: Hirayama