Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

ABSTRACT

Solubility equilibria of the chiral N-methylephedrine species in two chiral ionic liquids; (S)-2-(methoxycarbonyl) pyrrolidinium bis(trifluoromethylsulfonyl) amide ([(S)-2Pro-Me][NTF2]) and (1R,2S)-(-)-dimethylephedrinium bis(trifluoromethylsulfonyl) amide have systematically been studied. Solubility measurements were performed for (S)-2methoxycarbonyl) pyrrolidinium bis(trifluoromethylsulfonyl) amide ([(S)-2-Pro-Me][NTF2]) at temperatures between (278 and 308) K and (1R,2S)-(-)-dimethylephedrinium bis(trifluoromethylsulfonyl) amide at 308 K, both with different initial enantiomeric compositions of N-methylephedrine. Methanol as co-solvent was used to decrease the viscosity of the (S)-2-(methoxycarbonyl) pyrrolidinium bis(trifluoromethylsulfonyl) amide. The solubilities in (S)-2-(methoxycarbonyl) pyrrolidinium bis(trifluoromethylsulfonyl) amide increased with temperature increments. A considerable asymmetry was observed in the ternary solubility phase diagram of the chiral N-methylephedrine and (1R,2S)-(-)dimethylephedrinium bis(trifluoromethylsulfonyl) amide system. The accuracy of the solubility