[H-].[Na+].[Cl:3][C:4]1[CH:5]=[C:6]([C@@H:10]2[C@@H:15]([C:16]3[CH:21]=[CH:20][C:19]([Cl:22])=[CH:18][CH:17]=3)[NH:14][C:13](=[O:23])[CH2:12][CH2:11]2)[CH:7]=[CH:8][CH:9]=1.Br[CH:25]([CH2:30][CH3:31])[C:26]([O:28][CH3:29])=[O:27]>CC1CCCO1>[Cl:3][C:4]1[CH:5]=[C:6]([C@H:10]2[CH2:11][CH2:12][C:13](=[O:23])[N:14]([C@@H:25]([CH2:30][CH3:31])[C:26]([O:28][CH3:29])=[O:27])[C@@H:15]2[C:16]2[CH:17]=[CH:18][C:19]([Cl:22])=[CH:20][CH:21]=2)[CH:7]=[CH:8][CH:9]=1To a 50° C. solution of 33.8 g (60% in mineral oil, 845 mmol) of sodium hydride in 2-methyltetrahydrofuran (550 mL) was added a solution of 240 g (750 mmol) of (5R,6S)-5-(3-chlorophenyl)-6-(4-chlorophenyl)piperidin-2-one (Example 1, Step E) in 2-methyltetrahydrofuran (550 mL) over a period of 45 min. After an additional 1.25 h at 50° C., 105 mL (912 mmol) of methyl 2-bromobutyrate was added over a 20 min period. The resulting slurry was stirred at 50° C. for 3.5 h, and then was cooled to room temperature and quenched with saturated aq. NH4Cl solution. Water was added to dissolve the precipitate and the resulting mixture was extracted with ethyl acetate (4×). The combined organic layers were washed with sat. aq. NaCl solution (1×), dried over Na2SO4, filtered and the filtrate was concentrated. Purification of the residue by chromatography on silica gel (Biotage® Snap™ column (Biotage, LLC, Charlotte, N.C.), 0 to 35% EtOAc/DCM, gradient elution) provided the title compound as a white oily solid.
読み込み中…