A free ligand for the asymmetric dihydroxylation of olefins utilizing one-phase catalysis and two-phase separation

A free cinchona alkaloid derivative, which can be recovered and reused in the same way as the reported soluble polymer-supported cinchona alkaloid-derived ligands, was applied to the homogeneous asymmetric dihydroxylation of olefins. The molar ratio of ligand/olefin was 5%, being much lower than that required for the corresponding soluble polymer-supported ligands (10–25%). Yields of 82–93% and ees of 89–99% have been obtained.