Phenylhydrazine → 7-methoxy-1-phenyl-1H-pyrazolo[3,4-b]quinolin-3-amine

Participants

Reaction Steps

To a suspension of 4.8 g sodium hydride (60%) in 200 ml dimethylformamide at 0° C. was added a solution of 9.9 ml phenylhydrazine in 250 ml dimethylformamide over a 15 min period. The mixture was stirred and allowed to warm to room temperature for 1 hour. 2-Chloro-7-methoxy-3-quinolinecarbonitrile (Example 3c) (19.68 g) was then added in portions. The reaction mixture was stirred overnight at room temperature, and then heated on a steam bath for two hours. Since starting material was still present, additional sodium hydride (3.2 g) was added and heating continued until thin layer chromatography indicated that no starting material remained. The mixture was quenched in saturated ammonium chloride solution and the mixture worked up in ethyl acetate solution. The crude product was purified by chromatography and recrystallized from ethyl acetate to give 2.3 g 7-methoxy-1-phenyl-1H-pyrazolo[3,4-b]quinolin-3-amine, brown solid, m.p. 159°-160° C.

Provenance & Evidence