C(OC([N:11]1[CH2:16][CH2:15][CH:14]([C:17]2[NH:18][C:19]([C:28]3[CH:33]=[CH:32][C:31]([Cl:34])=[C:30]([Cl:35])[CH:29]=3)=[C:20]([C:22]3[CH:27]=[CH:26][N:25]=[CH:24][CH:23]=3)[N:21]=2)[CH2:13][CH2:12]1)=O)C1C=CC=CC=1>Br.C(O)(=O)C>[Cl:35][C:30]1[CH:29]=[C:28]([C:19]2[NH:18][C:17]([CH:14]3[CH2:15][CH2:16][NH:11][CH2:12][CH2:13]3)=[N:21][C:20]=2[C:22]2[CH:23]=[CH:24][N:25]=[CH:26][CH:27]=2)[CH:33]=[CH:32][C:31]=1[Cl:34]4-[5-(3,4-Dichlorophenyl)-4-pyridin-4-yl-1H-imidazol-2-yl]piperidine-1-carboxylic acid benzyl ester (3.8 g, 7.5 mmol) dissolved in hydrogen bromide (30 wt. %) in acetic acid (20 mL) was heated to 80° C. for one hour, after which time the reaction mixture was allowed to cool to ambient temperature and concentrated at reduced pressure. The residue was then dissolved in hydrochloric acid (100 mL of 1N) and extracted with ethyl acetate (100 mL). The aqueous layer was then basified with sodium hydroxide (35 mL of 3N) and buffered with saturated aqueous sodium hydrogen carbonate (300 mL). The aqueous layer was extracted with chloroform (5×200 mL) and the organic layers combined, dried over anhydrous sodium sulfate, filtered and concentrated at reduced pressure. The resulting foam was crystallized from ethyl acetate/hexane to give the free amine (2.2 g).
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