Nitric Acid → HCID 20383929, compound

Participants

Reaction Steps

To a stirred, cooled solution of 40 ml. of concentrated sulfuric acid (at 0°-5° C.) was added, dropwise, 4.0 g. (0.015 mole) of 1-ethyl-2-methyl-5-methylsulfonyl-6-chlorobenzimidazole. Stirring was continued until all solid was in solution. To this stirred and cooled solution was added 6.0 g. (0.086 mole) of 90% fuming nitric acid, dropwise, over a 30 minute period. Stirring was continued while cooling for 9 hours and then the reaction mixture allowed to warm to room temperature over a 14 hour period. An additional 13.5 g. of 30% fuming sulfuric acid was then added, dropwise. The reaction mixture was stirred for about 24 hours and then stirred at about 40° C. for an additional 64 hours. The resultant reaction mixture was poured into a stirred mixture of 300 ml. of ice +200 ml. of concentrated ammonium hydroxide. The resultant aqueous mixture was extracted thrice with 100 ml. portions of chloroform and the combined chloroform extracts dried over anhydrous sodium sulfate. The resultant chloroform solution was evaporated to dryness under reduced pressure to give 3.04 g. (73.4%) of the desired product, melting at 75°-79° C.

Provenance & Evidence