Hydrochloric Acid → N-(2,5-difluorophenyl)benzenesulfonamide

Participants

Reaction Conditions

Reaction Steps

0.194 mole (25 g) of 2,5-difluoroaniline is added to 125 ml of pyridine. 0.2 mole (25.5 ml) of benzenesulphonyl chloride is added, while the temperature is between 35° C. and 45° C. The temperature is maintained at 40° C. for 1 hour after the addition is completed, and then the reaction mixture is poured onto 1 kg of ice and water to which 100 ml of concentrated hydrochloric acid have been added. The expected product precipitates. After filtration and washing, it is treated with a normal sodium hydroxide solution in order to remove insoluble material. The soda-containing filtrate is neutralized with concentrated hydrochloric acid. The expected product, which has precipitated, is filtered off, washed to neutrality and recrystallized from acetic acid. It melts at 115° C.

Provenance & Evidence