[C:1]1([CH2:7][CH2:8][CH2:9][N:10]2[CH2:15][CH2:14][CH2:13][CH:12]([C:16]3[CH:21]=[CH:20][CH:19]=[C:18]([O:22]C)[CH:17]=3)[CH2:11]2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.Br.C(=O)([O-])[O-].[Na+].[Na+]>C(O)(=O)C>[C:1]1([CH2:7][CH2:8][CH2:9][N:10]2[CH2:15][CH2:14][CH2:13][CH:12]([C:16]3[CH:21]=[CH:20][CH:19]=[C:18]([OH:22])[CH:17]=3)[CH2:11]2)[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1To a stirred solution of 15.2 g (0.049 mole) of 1-(3-phenylpropyl)-3-(3-methoxyphenyl)piperidine from Preparation 1 in 75 ml of glacial acetic acid was added 150 g of 48% aqueous hydrobromic acid. The reaction mixture was heated at 120° C. for 2.5 hours and then it was poured onto ice. The resulting mixture was basified with sodium carbonate and then it was extracted with ethyl acetate. The extracts were washed with water, followed by sodium chloride solution, and then they were dried and evaporated to give 17.2 g of crude product as a tan solid. Purification by recrystallization from a mixture of ethyl acetate/hexane/triethylamine (5:5:0.5) gave 4.0 g (28%) of the title compound, m.p. 119°-120° C.
Loading…
