405224-24-0

405224-23-9

405224-24-0

General procedure for the synthesis of 3-amino-5-bromo-1H-pyrazolo[3,4-b]pyridine from 5-bromo-2-chloronicotinonitrile: Compound 3 (5-bromo-2-chloronicotinonitrile, 307 mg, 1.4 mmol) was dissolved in ethanol (10 mL) in a microwave reactor tube, followed by the addition of 5 equiv. of hydrazine hydrate (NH2NH2-H2O) to the solution. The reaction mixture was placed in a microwave reactor and radiated at 170 °C for 10 min. Upon completion of the reaction, the solvent was removed by rotary evaporator to afford the target product 3-amino-5-bromo-1H-pyrazolo[3,4-b]pyridine (4) in quantitative yield.