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ROZRÓŻNIANIE MOLEKUŁ A SPEKTROSKOPIA NMR W CIECZY 69

ABSTRACT

The high resolution NMR spectroscopy in liąuids is aconvenient tool for diffe-rentiating stereoisomers. Diastereomeric structures havingdifferent spatial distribu-tion of electron density produce different magnetic environments for their nuclei and in conseąuence have, in generał, different NMR spectra. The same concems diastereotopic groups in a molecule. On the other hand, enantiomers or enantiotopic groups can be difFerentiated only when they are placed in a chiral environmenL It can be accomplished by transforming enantiomers into their diastereomeric deriva-tives with the aid of chiral derivatising reagents, or by using chiral complexing or solvating agents. The most popular methods of practical realization of these appro-aches have been reviewed and illustrated with some examples. The spectroscopic differentiation of enantiomers provides a possibility of determining their absolute configurations.

Keywords: distinguishability of molecules, NMR in liquids, chiral reagents, chiral recognition

Słowa kluczowe: rozróżnialność molekuł, NMR w cieczach, odczynniki chiralne, rozróżnianie enancjomerów