The potential of chiral solvents in enantioselective crystallization

The objective of this thesis is to evaluate the potential of applying chiral solvents for crystallization-based resolution of racemates. In general, it can be expected that a chiral solvent can discriminate two enantiomers by creating some weak interactions between the solvent and the substrate molecules forming diastereomeric complexes with different physical properties. This may lead to either asymmetry in the solubility phase diagrams or selective kinetic effects which can be employed for resolution purposes. To evaluate the prospect of using chiral solvents for crystallization based enantioseparation and to evaluate the potential of this approach, systematic experimental work is required. The chosen model systems studied experimentally in this work are two pharmaceutically interesting substances (mandelic acid and N-methylephedrine) which belong to the compound and conglomerate forming systems, respectively. Three different types of chiral solvents were studied: a “classical” chiral solvents, a chiral ionic liquids and a tailor-made chiral solvents.