chiral oxazaborolidine prepared from (S)-α,α-diphenyl-2-pyrrolidinemethanol and Me3SiCH2B(OH)2; benzo[1,3,2]dioxaborole in toluene T=-78°C;

[(R,R)-N-(p-toluenesulfonyl)-1,2-diphenylethylenediamine](p-cymene)ruthenium in dichloromethane; isopropyl alcohol 1.5 h; Inert atmosphere; optical yield given as percent ee;