[Br:1][C:2]1[CH:7]=[CH:6][C:5]2[C:8]3[C:9](=O)[NH:10][CH2:11][CH2:12][CH2:13][C:14]=3[O:15][C:4]=2[CH:3]=1.B.C1COCC1>C1COCC1>[Br:1][C:2]1[CH:7]=[CH:6][C:5]2[C:8]3[CH2:9][NH:10][CH2:11][CH2:12][CH2:13][C:14]=3[O:15][C:4]=2[CH:3]=1To a slurry of the product of step C (858 mg, 3.06 mmol) in anhydrous THF (6 mL) was added 1 M borane-THF complex (1 N in THF, 15.3 mL, 15.3 mmol) at ambient temperature. The reaction mixture was heated to 65° C. for 15 h. After cooling to ambient temperature, the reaction mixture was quenched with 1 M HCl and concentrated in vacuo. The residue was basified with 1 M NaOH and extracted with dichloromethane. The organic layer was dried over sodium sulfate, filtered, and concentrated in vacuo to give the crude material which was purified by flash column chromatography (SiO2, 90:10 dichloromethane/methanol) to provide 8-bromo-2,3,4,5-tetrahydro-1H-benzofuro[3,2-c]azepine (369 mg, 45%) as a pale yellow solid: 1H NMR (CDCl3, 300 MHz) δ 7.53 (d, J=1.8 Hz, 1H), 7.33-7.28 (m, 1H), 7.21 (d, J=8.4 Hz, 1H), 3.95 (s, 2H), 3.18 (td, J=3.9, 2.4 Hz, 2H), 3.00 (t, J=6.0 Hz, 2H), 1.94-1.84 (m, 2H), 1.57 (s, 1H).
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