Nitric Acid → HCID 15291316, compound

Participants

Reaction Conditions

Reaction Steps

5-Chloro-1-isopropyl-2-(4-methyl-1-piperazinyl)benzimidazole (24.1 g) was dissolved in concentrated sulfuric acid (160 ml). To the solution were added dropwise concentrated nitric acid (7.8 g) and concentrated sulfuric acid (20.2 g) at 0° C. and the mixture was stirred at 0° C. for 5 minutes. The reaction mixture was poured into water and the mixture was made basic with an aqueous sodium hydroxide solution and extracted with chloroform. The chloroform layer was washed with water and dried over anhydrous magnesium sulfate and then the solvent was distilled off under reduced pressure to give 5-chloro-1-isopropyl-2-(4-methyl-1-piperazinyl)-6-nitrobenzimidazole (25.5 g). A part of the obtained product was recrystallized from acetonitrile, which showed the physical properties consistent with those in Preparation 8.

Provenance & Evidence