Benzenesulfonamide → 6-Benzenesulfonylcarbamoyl-1-(2-chlorobenzyl)-2-methylbenzimidazole

Participants

Reaction Steps

N,N′-carbonyldiimidazole (5.41 g) was added at a time to a solution of 5.02 g of 6-carboxy-1-(2-chlorobenzyl)-2-methylbenzimidazole in 110 ml of N,N-dimethylformamide, and the mixture was stirred at room temperature for 1 hour. Subsequently, a solution of 5.24 g of benzenesulfonamide and 5.08 g of diazabicycloundecene in 20 ml of N,N-dimethylformamide was added thereto, and the mixed solution was stirred at 100° C. for 70 hours. The reaction solution was cooled, and the solvent was distilled off under reduced pressure. Water and chloroform were added to the residue, and 10% hydrochloric acid was added thereto while being stirred until the aqueous layer was acidified. The solution was extracted twice with chloroform. The organic layer was washed with a saturated aqueous solution of sodium hydrogencarbonate, and a part of the solvent was distilled off under reduced pressure. The crystals precipitated were separated through filtration, and were dried to give 4.96 g of 6-benzenesulfonylcarbamoyl-1-(2-chlorobenzyl)-2-methylbenzimidazole (163).

Provenance & Evidence