Organocatalytic Asymmetric Tandem -Aminooxylation-Henry Reactions for the Synthesis of 1,2-Diols: Total Synthesis of (-)-l-threo-Sphinganine

A new and rapid asymmetric synthesis of anti- and syn-,-dihydroxynitroalkanes through an organocatalytic tandem -aminooxylation-Henry reaction is described. The target diol derivatives were synthesized in good yields, with excellent enantioselectivities, and low to moderate diasteroselectivities, under mild conditions. The synthesis of the antineoplastic and antipsoriatic drug (-)-l-threo-sphinganine demonstrates the synthetic utility of the building blocks generated in the developed reaction.