49674-16-0

49674-15-9

49674-16-0

General procedure for the synthesis of 5-amino-3-bromobenzonitrile from 3-bromo-5-nitrobenzonitrile: 3-bromo-5-nitrobenzonitrile (3 g, 13.2 mmol) was dissolved in methanol (100 mL) and cooled in an ice water bath. To this solution zinc powder (3.46 g, 52.9 mmol) and acetic acid (6.05 mL, 106 mmol) were added sequentially. Exothermic phenomenon was observed 1 minute after the start of the reaction. After the reaction was carried out for 2 hours, the reaction mixture was filtered through diatomaceous earth and the filtrate was concentrated to give the crude product. The crude product was purified using silica gel chromatography with a hexane solution of 0 to 50% ethyl acetate as eluent. The eluate containing the target product was collected and concentrated by evaporation to give 5-amino-3-bromobenzonitrile (2.1 g, 81% yield). The product was analyzed by high performance liquid chromatography (HPLC): retention time (RT) = 0.80 min (Waters Acquity UPLC BEH C18 column, 1.7 μm, 2.0 × 50 mm, mobile phase acetonitrile/water/0.05% trifluoroacetic acid, gradient elution, detection wavelength = 254 nm); mass spectrum (ES): m/z = 196.9/ 198.9 (79Br/81Br)[M+H]+; 1H NMR (DMSO-d6) δ 7.06-7.09 (m, 1H), 7.04 (t, J=2.0Hz, 1H), 6.87 (dd, J=2.1,1.4Hz, 1H), 5.91 (s, 2H).