Nitric Acid → 1-Methyl-4-nitropyrrole-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

Acetic anhydride (20 mL) was treated with nitric acid (4.0 mL, 70%) and the mixture heated to 50° C. for 15 min then cooled to room temperature, and slowly added to a suspension of 1-methyl-2-pyrrolecarboxylic acid (4 g, 15.98 mmol) in of Ac2O (12 mL) cooled to −25° C. The mixture was stirred at −15° C. for 0.5 hr, then the temperature was allowed to rise to ambient, and stirring was continued for 20 min. The mixture was again cooled to −25° C. and the precipitate collected in a funnel cooled with dry ice, the solid was washed with a small quantity of cold Ac2O (−25° C.). The crystalline solid was taken up in water containing NaOH (1 g). Acidification with the HCl precipitated the pure compound. NMR as previously reported.

Provenance & Evidence