Asymmetric synthesis of (-)-pseudoephedrine from (2S,3S)-3-phenyloxiran-2-ylmethanol. Stereospecific interchange of amino and alcohol function

A ring-opening reaction of N-methylaziridines with Boc2O/NaI has been applied to the asymmetric synthesis of
pseudoephedrine. 3-Methylamino-3-phenyl-1,2-propanediol 1, derived from (2S,3S)-3-phenyloxiran-2-ylmethanol, was converted into the oxazolidin-2-one 4, a precursor of pseudoephedrine. The reaction occurs with a stereospecific interchange of amino and alcohol functions.