11.7 g of (2S)-1-(4-cyanophenoxy)-3-methanesulfonyloxy propane-2-ol, was stirred and refluxed overnight with ethyl (3-propylthio)propylamine (13.9 g), potassium carbonate (12.6 g) and acetonitrile (100 ml). Filtration and evaporation gave 21.5 g of crude product which was distributed between ether and 2 M hydrochloric acid. The aqueous layer was extracted three times with dichloromethane, in which it was present as an ion pair. Evaporation and distribution between ether and 1 M sodium hydroxide yielded the free base in the ether layer. Chromatography over silica using methanol-dichloromethane 5:95 as mobile phase gave 10.3 g of the title compound as a colourless oil, [α]D20 -24,2° (c 1.0, CH3OH).
