First example of asymmetric transfer hydrogenation in water induced by a chiral amino alcohol hydrochloride

The low-cost and commercially available (-)-ephedrine hydrochloride was firstly employed in the [RuCl2(1)-cymene)](2)-catalyzed asymmetric transfer hydrogenation of prochiral ketones in water. The reaction could be performed in the open air at rt, affording excellent yields (up to 99%) and good enantioselectivities (up to 83% ee). It provided a further step toward the discovery of simplified catalyst systems for eventual availability. (c) 2005 Published by Elsevier Ltd.