Formic Acid → [5-amino-1-(2-hydroxyethyl)-1H-pyrazol-4-yl]formamide

Participants

Reaction Conditions

Reaction Steps

To a suspension of 2-(4,5-diamino-1H-pyrazol-1-yl)ethanol sulfate (5 g) in dichloromethane (50 ml) was added triethylamine (6.38 ml) at 0° C., and the mixture was stirred at 0° C. for 10 minutes. A mixture of acetic anhydride (2.16 ml) and formic acid (1.74 ml) was stirred at 40° C. for 30 minutes, cooled to 0° C. and added dropwise to the above solution at 0° C. The whole mixture was stirred at 0° C. for 2 hours. To the mixture was added brine, and the whole mixture was extracted with tetrahydrofuran. The extract was dried over magnesium sulfate and evaporated under reduced pressure to give crude [5-amino-1-(2-hydroxyethyl)-1H-pyrazol-4-yl]formamide, which was used in the next reaction without further purification.

Provenance & Evidence