Nitric Acid → 2-Chloro-4-nitropyridin-3-ol

Participants

Reaction Conditions

Reaction Steps

A solution of 2-chloro-3-pyridinol (11.3 g, 87.2 mmol) in concentrated sulfuric acid (25 mL) was cooled in an ice-bath and a 1:1 mixture of nitric acid and sulfuric acid (25 mL) was added slowly. After everything was added, solution was stirred at 0° C. for 1 hour and then at room temperature for another hour. Mixture was diluted with water and extracted with methylene chloride. Organic phases were dried over magnesium sulfate, filtered, and concentrated. Residue was purified by column chromatography on silica gel (ethyl acetate/hexane 2:1→3:1) to give 2-chloro-4-nitro-pyridin-3-ol as a tanned solid (3.58 g, 24%). 1HNMR (CDCl3, 400 MHz) δ 10.5 (s, 2H), 8.14-8.13 (d, J=5.5 Hz, 1H), 7.88-7.87 (d, J=5.5 Hz, 1H).

Provenance & Evidence