[Br:1]Br.[OH:3][C:4]1[C:14]2[CH2:13][CH2:12][N:11]([C:15](=[O:20])[C:16]([F:19])([F:18])[F:17])[CH2:10][CH2:9][C:8]=2[CH:7]=[CH:6][CH:5]=1>C(#N)C>[Br:1][C:7]1[C:8]2[CH2:9][CH2:10][N:11]([C:15](=[O:20])[C:16]([F:19])([F:17])[F:18])[CH2:12][CH2:13][C:14]=2[C:4]([OH:3])=[CH:5][CH:6]=1Add dropwise bromine (10.8 mL, 0.21 mol) in acetonitrile (260 mL) to a slurry of 6-hydroxy-3-(2,2,2-trifluoroacetyl)-2,3,4,5-tetrahydro-1H-benzo[d]azepine (51.8 g, 0.2 mol) in acetonitrile (400 mL) at 0° C. cooling with ice-water to keep the temperature between 2-5° C. Warm the reaction to ambient temperature and stir for 30 min. Pour the mixture into ice-cold water (2 L) to obtain a white precipitate. Collect the solid by vacuum filtration, wash with water and dry under vacuum at 105° C. Recrystallize the crude material in toluene/heptane and cool the mixture in an ice bath. Collect the solid by vacuum filtration, wash with heptane and dry under vacuum at 105° C. to obtain the desired intermediate as a white solid (54.63 g, 81%). MS (ES+) m/z: 338 (M+H)+.
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