[C:1]1([C:7]2[N:8]=[C:9]([C@@H:18]3[CH2:20][O:19]3)[O:10][C:11]=2[C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[CH:21]([Mg]Cl)=[CH2:22]>C1COCC1.[Cu]I>[C:1]1([C:7]2[N:8]=[C:9]([C@@H:18]([OH:19])[CH2:20][CH:21]=[CH2:22])[O:10][C:11]=2[C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1To a solution of (2S)-2-(4,5-diphenyloxazol-2-yl)oxirane (12 g) and CuI (0.19 g) in THF (240 ml) was dropwise added a solution of vinylmagnesium chloride in THF (1.0 M solution, 101 ml) at -78° C. under N2. The mixture was stirred for 1 hour at room temperature and partitioned between ethyl acetate and water. The organic layer was washed with 1N-HCl, water, sat. NaHCO3 and brine. The dried solvent was evaporated in vacuo and the residue was purified by chromatography on silica gel to give (4S)-4-(4,5-diphenyloxazol-2-yl)-4-hydroxy-1-butene (9.2 g). MS (m/z): 292 (M+ +1) IR (Nujol): 3300, 1600 cm-1NMR (CDCl3, δ): 2.7-2.9 (2H, m), 3.17 (1H, d, J=5.8 Hz), 4.8-5.0 (1H, m), 5.1-5.3 (2H, m), 5.8-6.0 (1H, m), 7.2-7.8 (10H, m)
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