ASYMMETRIC REDUCTION OF A CARBON-NITROGEN DOUBLE-BOND - ENANTIOSELECTIVE SYNTHESIS OF 4,5-DIHYDRO-3H-2,3-BENZODIAZEPINES

A highly specific enantioselective reduction, elaborated for the reduc tion of the 3,4-carbon-nitrogen double bond of -(4-nitrophenyl)-4,5-di hydro-3H-2,3-benzodiazepine 4 made possible the synthesis of the enant iomers of the potent non-competitive AMPA/kainate antagonists 2a, b. N MR Investigations of the reducing complex show that there is no format ion of an 1,3,2-oxazaborolidine ring as may have been presumed on the basis of literature data.