Ionic liquids -: Some reflections on their use in asymmetric homogeneous catalysis

Purpose of Review The purpose of this review is to demonstrate the possible impact of application of ionic liquids in stereoselective catalytic reactions providing optically pure isomers, in comparison with standard homogeneous methods. Their effective action consists in their chemical structure, which is briefly discussed here, but mainly in their unusual multi-phase behaviour. Findings An interesting and promising alternative to immobilized chiral complexes used as stereoselective catalysts is based on utilisation of ionic liquids as reaction solvents. These modem and environmental-friendly solvents allow to carry out the reaction in several phase configurations varying from monophasic and biphasic to reversibly biphasic systems. Conclusions Ionic liquids are suitable solvents for homogeneous or heterogeneous catalytic processes catalysed by chiral transition metal complexes.