Nitric Acid → 2,4-Dimethyl-5-nitro-1H-imidazole (9CI)

Participants

Reaction Conditions

Reaction Steps

Sulfuric acid (30 ml, 0.56 mole) was added dropwise to 2,4-dimethylimidazole (10 g, 0.104 mole), and urea (6.24 g, 0.104 mole), in a 1 l. flask cooled in ice. This was followed by the addition of fuming nitric acid (30 ml, 0.72 mole). When all had been added, the flask was heated at 200° C. for 1-2 minutes, whereupon a vigorous reaction ensued, necessitating the removal of the heat. When the reaction subsided, heating is continued for 10 minutes. The flask was then allowed to cool, and the reaction mixture was added to 300 ml of H2O. The solution was adjusted to pH 5 with aqueous sodium hydroxide (about 40 g of sodium hydroxide was required). The resulting precipitate was filtered off and dried in vacuum to give 9.9 g of 2,4-dimethyl-5-nitroimidazole.

Provenance & Evidence