To a solution of (S)-5-(4-cyclohexyl-phenoxymethyl)-4,5-dihydro-oxazol-2-ylamine (1.0 g, 3.64 mmol), prepared in accordance with the procedures as set forth in Steps 1 and 2 of Example 1 and starting from R-epichlorohydrin and 4-cyclohexylphenol, in ethanol (18.2 mL) was added ethyl 2-pentynoate (0.92 g, 7.28 mmol). The reaction mixture was heated at reflux for 14 hrs and then gradually cooled to room temperature. The resulting crystalline solid was isolated by filtration, washed with heptane 3 times, and dried under vacuum to afford 560 mg of (S)-2-(4-cyclohexyl-phenoxymethyl)-5-ethyl-2,3-dihydro-oxazolo[3,2-a]pyrimidin-7-one as a white solid. [α]D25 −27.96 (c 0.526, CHCl3).
