[Synthesis]
General procedure for the synthesis of 6-bromoisoquinolin-3-amine from 1,6-dibromoisoquinolin-3-amine: 1,6-dibromoisoquinolin-3-amine (13.5 g, 45 mmol), ammonium formate (10.8 g, 172 mmol), and tetrakis(triphenylphosphine)palladium(0) (3.45 g, 3.0 mmol) were dissolved in 50 mL of DMF and the mixture was transferred to a 350 mL screw cap flask, sealed and heated at 50 °C for 48 hours. Subsequently, tetrakis(triphenylphosphine)palladium(0) (950 mg) and ammonium formate (3.0 g) were added supplementally to the reaction mixture and heating was continued at 50 °C for 48 hours. After completion of the reaction, the mixture was cooled to room temperature, the solid was collected by filtration, washed with a small amount of DMF and then with ether, and finally dried under vacuum at 50 °C to give the yellow amorphous solid product 6-bromoisoquinolin-3-amine (10.4 g, 90% yield). The product was detected by LCMS (API-ES), m/z: 222.9, 224.9 [M + 1]. 1H NMR (300MHz, DMSO-d6) δppm 8.81 (s, 1H), 7.80 (d, J = 1.6Hz, 1H), 7.73 (d, J = 8.8Hz, 1H), 7.22 (dd, J = 8.6, 1.9 Hz, 1H), 6.55 (s, 1H), 6.12 (s, 2H). |