3-[4-(8,9-Dihydro-7H-benzocyclohepten-5-yl)-phenyl]-acrylic Acid Methyl Ester → 3-[4-(6-Bromo-8,9-dihydro-7H-benzocyclohepten-5-yl)-phenyl]-acrylic Acid Methyl Ester
Reaction equation
[CH3:1][O:2][C:3](=[O:23])[CH:4]=[CH:5][C:6]1[CH:11]=[CH:10][C:9]([C:12]2[C:18]3[CH:19]=[CH:20][CH:21]=[CH:22][C:17]=3[CH2:16][CH2:15][CH2:14][CH:13]=2)=[CH:8][CH:7]=1.C1C=C[NH+]=CC=1.[Br:30][Br-]Br>C(Cl)Cl>[CH3:1][O:2][C:3](=[O:23])[CH:4]=[CH:5][C:6]1[CH:11]=[CH:10][C:9]([C:12]2[C:18]3[CH:19]=[CH:20][CH:21]=[CH:22][C:17]=3[CH2:16][CH2:15][CH2:14][C:13]=2[Br:30])=[CH:8][CH:7]=1Participants
3
Procedure
To a solution of the olefin (2b) (5.44 g, 17.9 mmol) in CH2Cl2 (300 mL) at 0° C. was added pyridinium bromide perbromide (90%, 7.0 g, 19.6 mmol) in portions over 0.5 h. After stirring 1 h the solution was washed with water, sat. NaHSO3, water and was dried (MgSO4). The solvent was removed under reduced pressure to give the bromide (2c) as an oil (6.85 g, 100%): 1H NMR (CDCl3) δ 7.69 (d, J=16.1 Hz, 1H), 7.50 (d, J=8.1 Hz, 2H), 7.20 (m, 5H), 6.80 (d, J=7.3 Hz, 1H), 6.43 (d, J=16.1 Hz, 1H), 3.81 (s, 3H), 2.79 (t, J=7.0 Hz, 2H), 2.60 (t, J=7.0 Hz, 2H), 2.30 (m, 2H); APcI m/z: 424 (M+H+CH3CN+, 100%).