Efficient synthesis of (2R,3S)- and (2S,3S)-2-amino-1,3,4-butanetriols through stereodivergent hydroxymethylation of d-glyceraldehyde nitrones

The nucleophilic addition of two alkoxymethyllithium derivatives to three d-glyceraldehyde derived nitrones has been investigated. The diastereofacial selectivity of the reaction could be controlled by the appropriate use of Lewis acids as precomplexing agents of the nitrones. The obtained syn and anti adducts were further converted into C-4 building blocks and β-hydroxy-α-aminoacids.