Hydrochloric Acid → 4-Sulfamoylbenzene-1-sulfonyl chloride

Participants

Reaction Steps

To a mixed solution of 80 ml water and 50 ml of concentrated hydrochloric acid was added 25.0 g (145 mmol) of 4-aminobenzenesulfonamide followed by stirring. An aqueous solution (20 ml) of 10.5 g (152 mmol) of sodium nitrite was added dropwise thereinto at −13° C. to −10° C. during 15 min. After 10 min, the reaction solution was added to a mixed solution saturated with sulfur dioxide (prepared by saturating sulfur dioxide in a mixed solution of 150 ml of acetic acid and 12.5 ml of concentrated hydrochloric acid followed by adding 3. 7 g of cuprous chloride) at −30° C. under stirring. After 1 hr, 500 ml of ice water was added to the reaction solution, and the resulting precipitates were collected by filtration. The precipitates were dissolved in a mixed solution of 450 ml of toluene and 150 ml of ethyl acetate. After the resulting insoluble matters were filtered off, the filtrate was extracted with ethyl acetate. The organic layer was washed with a saturated sodium bicarbonate solution and brine successively, and dried over magnesium sulfate. The solvent was evaporated, 100 ml of toluene was added to the resulting residue and the crystals were collected by filtration to give20.9 g of the title compound.

Provenance & Evidence