Water → 5-Nitropicolinic acid

Participants

Reaction Conditions

Reaction Steps

Diethyl 2-(5-nitropyridin-2-yl)malonate (67.47 g) was stirred in water and aqueous sodium hydroxide solution (2N) was added followed by potassium permanganate (42 g) causing the reaction temperature to rise to 60° C. Further portions of aqueous sodium hydroxide solution and potassium permanganate were added maintaining the reaction temperature at 60°-70° C. After the final addition, the suspension was stirred at 60° C. for 1.5 hours. The hot suspension was then filtered through `Hyflo Supercel`. The filter cake was washed with aqueous sodium hydroxide solution (2N). On cooling to room temperature, the filtrate was carefully acidified to pH 1-2 with concentrated hydrochloric acid. The resulting precipitate was collected by filtration and dried to yield 5-nitropyridine-2-carboxylic acid (26.17 g) as a fawn solid, m.p. 210°-211° C.

Provenance & Evidence