Saccharin → N-(phenylsulfonyl)-benzo-1,2,3-thiadiazole-7-carboxylic acid amide

Participants

Reaction Steps

After the addition of a spatula tip of 4-dimethylaminopyridine to a suspension of 4 g of the sodium salt of saccharin in 60 ml of methylene chloride, a solution of 3.9 g of benzo-1,2,3-thiadiazole-7-carboxylic acidchloride in 20 ml of methylene chloride is added dropwise at a maximum of 20° C. The mixture is stirred overnight at room temperature and thenext day the suspension is poured onto ice-water and extracted with ethyl acetate. The extracts are washed with dilute sodium hydrogen carbonate solution and water, dried and concentrated by evaporation. The residue is recrystallised from tetrahydrofuran/hexane to yield the title compound having a melting point of 173°-175° C.

Provenance & Evidence