Intramolecular vs. intermolecular induction in the diastereoselective catalytic reduction of enantiomerically pure ketones with borane in the presence of cyclic β-amino alcohols

Article abstract of DOI:10.1016/0957-4166(95)00404-1

Asymmetric reduction of various enantiomerically pure ketones was carried out by using oxazaborolidine catalysts with a variety of achiral and chiral ligands. The efficiency of chiral 1,2-amino alcohols as well as the effect of the stereogenic centers in the substrate on the catalytic asymmetric reduction were studied. It was found that the corresponding secondary alcohols were obtained with extremely high stereoselectivities with the proper choice of chiral ligands although a considerably large double asymmetric induction was observed in some cases.