Hydrochloric Acid → HCID 58196600, compound

Participants

Reaction Conditions

Reaction Steps

N-Cyclopropyl-2-(methylthio)pyrazolo[1,5-a][1,3,5]triazin-4-amine (1.0 eq, 3.10 g, 14.00 mmol) was dissolved in anhydrous DMF (50 ml) under nitrogen atmosphere. Phosphorus oxychloride (5.0 eq, 6.4 ml, 69.9 mmol) was added dropwise over 5 minutes. Internal temperature rose to 45° C. The reaction was stirred in an oil bath at 70° C. for 4.5 hours. The mixture was cooled down and added dropwise into a solution of 6N NaOH (150 ml) chilled with an ice bath. The rate of addition was adjusted to maintain the internal temperature of the aqueous NaOH below 16° C. At the end of the addition, the mixture was neutralized by slow addition of 6N HCl to reach pH=5-6. The resulting solid was filtered, washed with water and dried in a vacuum oven overnight. 4-(cyclopropylamino)-2-(methylthio)pyrazolo[1,5-a][1,3,5]triazine-8-carbaldehyde was isolated as tan solid (9.26 g, 93%). LCMS (ES):>95% pure, m/z 250 [M+H]+.

Provenance & Evidence