Asymmetric synthesis of meso- and (2R,4R)-2,4-diaminoglutaric acids

In order to synthesize meso- and (2R,4R)-2,4-diaminoglutaric acids, a synthetic route has been developed starting from Garner's aldehyde and where the key steps are the asymmetric hydrogenations of (E)- and (Z)-(R)-3-tert-butoxycarbonyl-2,2-dimethyl-4-[2'-(benzamido)-2'-(methoxycarbonyl)ethenyl]-1,3-oxazolidine, under heterogeneous conditions, followed by oxidation and further hydrolysis. A model is proposed to explain the stereochemical outcome of the asymmetric hydrogenation. (C) 1997 Elsevier Science Ltd.