Nitric Acid → 3-Fluoro-4-nitropyridin-1-ium-1-olate

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-fluoropyridine N-oxide (3-2) (10.4 g, 90 mmol) in sulfuric acid (52 mL) stirring at 120° C. was added fuming nitric acid (21 mL) over 1 hour. After stirring at 120° C. for another 3 hours, the reaction mixture was cooled to ambient temperature and poured into 300 mL of ice. The pH of the solution was adjusted to pH 7 by addition of 20% sodium hydroxide, and extracted with chloroform. The organic layer was dried, filtered and concentrated. The residue was recrystallized from diethyl ether/hexane to give a pale yellow solid (7.5 g, 51%). 1H NMR (400 MHz, CDCl3): 8.05 (m, 2H), 8.22 (m, 1H)

Provenance & Evidence