Formic Acid → 5-Formamido-1-(2-hydroxyethyl)pyrazole

Participants

Reaction Steps

A mixture of acetic anhydride (44.5 ml) and formic acid (22.3 ml) was stirred at room temperature for an hour. To this mixture was added 5-amino-1-(2-hydroxyethyl)pyrazole (30 g) at 0°-10° C., and the mixture was stirred under ice-cooling for 30 minutes. The mixture was poured into ice-cooled water, adjusted to pH 10.5 with 40% potassium carbonate solution, and stirred under ice-cooling for 30 minutes. The mixture was extracted with a mixture of tetrahydrofuran and ethyl acetate 6 times. The organic layer was dried over magnesium sulfate, and evaporated in vacuo to give 5-formamido-1-(2-hydroxyethyl)pyrazole (30.8 g).

Provenance & Evidence