Hydrochloric Acid → 4-Chloro-1-methyl-3-nitro-1,2-dihydropyridin-2-one

Participants

Reaction Conditions

Reaction Steps

A suspension of 4-chloro-3-nitro-2-pyridone (1.00 g, 5.7 mmol), potassium carbonate (1.58 g, 11.5 mmol) and methyl iodide (4.07 g, 28.7 mmol) in N,N-dimethylacetamide (5 ml) were heated at 45° C. for 18 h. The mixture was allowed to cool to ambient temperature, poured into water (100 ml), layered with ethyl acetate (50 ml) and pH adjusted to 5 by the addition of 5N hydrochloric acid. The aqueous phase was extracted into ethyl acetate (2×100 ml), the combined organics were washed with water (2×100 ml) and brine (50 ml), dried over anhydrous sodium sulfate, filtered and evaporated to give a pale yellow solid. The solid was triturated with diethyl ether (20 ml), filtered and washed with diethyl ether (5 ml) and isohexane (10 ml) and left to air dry, to give 4-chloro-1-methyl-3-nitro-1H-pyridin-2-one (0.71 g, 66%) as a pale yellow solid: δH (360 MHz, DMSO) 3.36 (1H, dd, J 5 and 3), 3.54 (6H, s), 6.69 (2H, d, J 7), 8.09 (2H, d, J 7).

Provenance & Evidence