Tridentate chiral NPN ligands based on bis(oxazolines) and their use in Pd-catalyzed enantioselective allylic substitution in molecular and ionic liquids

NPN ligands based on the bis(oxazoline) skeleton can be prepared by a divergent method, which allows a high modularity both in the type of phosphorous group (phosphinite, phosphate, phosphane) and the substitution in the methylene bridge. The Pd complexes of these ligands can efficiently promote the allylic substitution both in molecular solvents and ionic liquids, with important effect of the nature of ligand, which also controls the partial recovery of the Pd catalyst in ionic liquid.