Synthesis of 3-sulfanylpropanols containing three consecutive stereocenters via tandem Michael-aldol reaction of enoylthioamides with acetals as key reaction

(2S,3S,1′R)-2-(α-Methoxybenzyl)-3-phenyl-3-sulfanylpropionamides were diastereoselectively prepared by the reactions of N-cinnamoyl-4S-isopropyl-5,5-dimethyloxazolidinethione with acetals in the presence of SnCl4. The absolute configuration of the three newly created contiguous stereocenters was determined by the X-ray analysis of the disulfide. The amides were transformed into propanols by the reductive removal of the oxazolidinone moiety.