The general procedure for the synthesis of 6-amino-5-bromonicotinonitrile from 2-amino-5-cyanopyridine is as follows:
Step 1: To a solution of 6-aminonicotinonitrile (102 mg, 0.86 mmol) in acetic acid (2 mL) was added a solution of bromine in acetic acid (0.86 mmol). The mixture was stirred at room temperature for 2 hours. After completion of the reaction, the solvent was removed by distillation under reduced pressure. The crude product was purified by rapid chromatography on silica gel (eluent: hexane/ethyl acetate, 3:1, v/v) to afford the title compound 6-amino-5-bromonicotinonitrile (110 mg, 65% yield).
The product characterization data are as follows:
1H-NMR (DMSO, 300 MHz): δ 8.26 (d, 1H, J = 2.0 Hz), 8.10 (d, 1H, J = 2.0 Hz), 7.24 (bs, 2H).
MS (APCI Neg): m/z 196, 198.
