Sulfuric Acid → Pyrazolo[1,5-a]pyrimidine-3-carboxamide

Participants

Reaction Steps

As shown hereinabove a pyrazolo(1,5-a)pyrimidine-3-carbonitrile (4) (prepared in the manner described in U.S. Pat. Nos. 4,281,000; 4,236,005 and 4,178,499) is stirred with concentrated sulfuric acid at room temperature for from 2-20 hours. The mixture is carefully poured onto ice and the precipitate is collected, neutralized with sodium hydroxide, ammonium hydroxide or saturated sodium bicarbonate and the like and washed with water to obtain the corresponding pyrazolo(1,5-a)pyrimidine-3-carboxamide compound (3).

Provenance & Evidence