Enantio- and Diastereoselective Syntheses of Orthogonally Protected anti-2-Amino-1,3,4-butanetriols from an Achiral (beta)Ketoester

An efficient enantio- and diastereoselective synthesis of orthogonally protected anti-2-amino-1,3,4-butanetriols from an achiral source is described. The anti relationship between the two adjacent aminated and hydroxylated carbons was controlled by sequential hydrogenation of a (beta)-ketoester in the presence of a chiral ruthenium catalyst and electrophilic amination of the resulting (beta)-hydroxyester.