Nitric Acid → 1-Methyl-6-nitro-2-(propan-2-yl)-5-(trifluoromethyl)-1H-benzimidazole

Participants

Reaction Steps

Slowly add 1.01 g. of 90% nitric acid dissolved in 2.2 ml. of concentrated sulfuric acid to a stirred solution of 3.00 g. of 2-isopropyl-1-methyl-5-trifluoromethylbenzimidazole in 13.2 ml. of concentrated sulfuric at about 5° C. Maintain the reaction at about 5° C for 2 hours. Pour the reaction mixture into 300 ml. of ice water and basify with 26 ml. of 50% sodium hydroxide followed by sodium carbonate. Extract with ether, dry over sodium sulfate and evaporate to dryness. Recrystallize from dichloromethane-hexane, obtaining the product of this example.

Provenance & Evidence