Hydrochloric Acid → 2-bromo-5-(dimethylsulfamoyl)benzoic Acid

Participants

Reaction Conditions

Reaction Steps

To 160 ml. of chlorosulfonic acid stirring at 0°-5° C. was gradually added 100.5 g. (0.33 mole) of 2-bromobenzoic acid. Stirring was continued as the temperature was allowed to increase to 25° C. The mixture was stirred and refluxed for three hours, then it was cooled and poured into ice-water. The solid was filtered and then washed with cold water until the filtrate was no longer acidic. The solid, thus isolated, was added, in portions, to 200 ml. of a 40% aqueous solution of dimethylamine. After being diluted with 500 ml. of water, the solution was made acidic with 2.5 N hydrochloric acid. Recrystallization of the precipitated solid from aqueous ethanol gave crystals of 2-bromo-5-dimethylaminosulfonylbenzoic acid, m.p. 170°-172° C.

Provenance & Evidence