CHIRAL OXAZABOROLIDINE DERIVATIVES; USE AS ENANTIOSELECTIVE CATALYSTS FOR REDUCTION OF PROCHIRAL KETONES TO CHIRAL ALCOHOLS

摘要

The anantoselective borane reduction of prochiral ketones to optically pure alcohols is effectively achieved by performing the reduction in the precence of catalytic amounts of the new and valuable oxazaborolidine compounds of formulas (I) and (II). The compounds of formulas (I) and (II) may be isolated and purified prior to use in the reduction reactions or the compounds of formulas (I) and (II) may be generated in situ.