Nitric Acid → 6-Amino-5-nitropyridine-3-sulfonic acid

Participants

Reaction Conditions

Reaction Steps

6-Aminopyridine-3-sulfonic acid (20 g) in concentrated H2SO4 (80 mL) was heated at 50° C. until it was completely dissolved. To this solution was added fuming HNO3 slowly over 20 minutes, so the internal temperature did not exceed 55° C. After the addition was complete, the reaction mixture was heated at 50° C. for 1 hour. After it was cooled to room temperature, it was poured into 150 g of ice. The mixture was stirred for another hour. The flask was cooled to 0° C., and was kept at 0° C. for another 2 hours. The solid was collected by filtration, and washed with cold 1:1 water/ethanol (20 mL), followed by diethyl ether (10 mL). The solid was dried in a vacuum oven overnight to provide the title compound.

Provenance & Evidence