[Cl:1][C:2]1[CH:25]=[CH:24][C:5]([C:6]([NH:8][CH2:9][CH2:10][N:11]2[CH2:15][CH2:14][CH2:13][CH:12]2[C:16]2[CH:21]=[CH:20][CH:19]=[C:18]([O:22]C)[CH:17]=2)=[O:7])=[CH:4][CH:3]=1.B(Br)(Br)Br>C(Cl)(Cl)Cl>[Cl:1][C:2]1[CH:3]=[CH:4][C:5]([C:6]([NH:8][CH2:9][CH2:10][N:11]2[CH2:15][CH2:14][CH2:13][CH:12]2[C:16]2[CH:21]=[CH:20][CH:19]=[C:18]([OH:22])[CH:17]=2)=[O:7])=[CH:24][CH:25]=1To a solution of 4-chloro-N-{2-[2-(3-methoxyphenyl)-1-pyrrolidinyl]ethyl }benzamide (0.58 g) in chloroform (30 ml) was added boron tribromide (99.0%, 0.61 ml) at -10° C., under nitrogen. The cooling bath was removed after 15 rains, and the reaction mixture was allowed to warm to ambient temperature. Crushed ice was added followed by 5:1-chloroform/2-propanol. The layers were separated, and the aqueous phase was extracted with 5:1 chloroform/2-propanol (2 times). The combined organic extracts were washed with saturated sodium bicarbonate, dried over anhydrous sodium sulfate, filtered, and the filtrate was concentrated. The residue was purified by flash column chromatography (silica gel, 30% ethyl acetate/dichloromethane). The appropriate fractions were collected and concentrated to afford 0.29 g (52%) of 4-chloro-N-{2-[2-(3-hydroxyphenyl)-1-pyrrolidinyl]ethyl}benzamide.
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