Ammonia → HCID 178505544, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-amino-6-(4-fluorophenyl)-5-(4-pyridyl)-1H-pyrazolo[3,4-b]pyridine (0.20 g, 0.7 mmol, obtained in example 70) in 48% HBr (1 mL) at 0° C., a solution of NaNO2 (0.05 g, 0.7 mmol) in water (0.1 mL) was added dropwise over a period of 15 minutes maintaining the temperature at 0-5° C. The mixture was stirred for 15 min at this temperature. Then, a solution of CuBr (0.24 g, 1.7 mmol) in 48% HBr (1 mL) was added slowly at 0° C. The resulting solution was stirred for 3 h at 0° C. It was allowed to reach room temperature, neutralized at pH 7 with saturated sodium bicarbonate and a 30% aqueous NH3. It was filtered and the solid was washed with a mixture of CH2Cl2 and water. The organic phase was washed with 1 N NaOH and the aqueous phase extracted with EtOAc. The combined organic phases were dried over Na2SO4 and concentrated to dryness. The crude product obtained was purified by chromatography on silica gel using CHCl3-MeOH mixtures of increasing polarity as eluent, to afford 50 mg of the title compound (yield: 21%).

Provenance & Evidence