Memory of Chiral Molecules Define Their Interactions and the Results of Resolution Processes
American Journal of Chemical Engineering
Volume 6, Issue 4, July 2018, Pages: 65-71
Received: May 15, 2018; Accepted: Aug. 10, 2018; Published: Sep. 21, 2018
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Emese Pálovics, Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, Budapest, Hungary
Elemér Fogassy, Department of Organic Chemistry and Technology, Budapest University of Technology and Economics, Budapest, Hungary
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The preparation of pure enantiomers has an increasing demand both for academic and industrial (pharmaceutical) practice. This is not surprising, because the active ingredients of a main part of medicines (about 70-80%) are pure enantiomers. Several selective methods are known for preparation of pure enantiomers but the more economical and usual method is the resolution, when the pure enantiomers are obtained from diastereomeric salts formed due the reaction of the racemic compound and resolving agent in adequate conditions (solvent, temperature crystallization time). Since the first resolution effectuated by Pasteur the researchers have tried to explain what is happening during resolution, but this has not yet been fully accomplished, it is still a mystery. In this paper is described our proposal for resolution’s mechanism, based on systematization of our results and observations made during the resolution, taking into consideration the principal characteristics of enantiomeric mixtures, namely the eutectic composition and their helicity. We suppose that the enantiomers have a memory and they used it during the resolution processes, tending to form their stable symmetric conformation.
Resolution, Enantiomers, Diastereomers, Eutectic composition, Homo- and Heterochiral Associates, Helical Structure
To cite this article
Emese Pálovics, Elemér Fogassy, Memory of Chiral Molecules Define Their Interactions and the Results of Resolution Processes, American Journal of Chemical Engineering. Vol. 6, No. 4, 2018, pp. 65-71. doi: 10.11648/j.ajche.20180604.15
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