Diastereoselective aldol condensation with 2-(β-ethoxycarbonyl)oxazolidine derived from norephedrine. A chiral masked synthon of ethyl formylacetate

Abstract Deprotonation of chiral masked synthetic equivalents of ethyl glyoxalate, derived from norephedrine, with a novel base formed by addition of tert -BuLi to tert -butyl formate, and subsequent reaction with aromatic aldehydes yields β-hydroxy esters in good yield and moderate to excellent diastereomeric excesses. Reductive transformation of the condensation products, and elimination of the chiral appendage leads to enantiomerically pure 2-aminomethyl-1,3-propanediol derivatives.