Hydrochloric Acid → 4-Sulfamoylbenzene-1-sulfonyl chloride

Participants

Reaction Steps

6.4 g (37.2 mmol) of 4-aminobenzenesulfonamide was added to a mixed solution of 12.5 ml of water and 6.3 ml of concentrated hydrochloric acid, followed by stirring. An aqueous saturated solution containing 2.56 g (37.1 mmol) of sodium nitrite was added drop wise there into at 0° C. or less. The reaction solution was added to an acetic acid solution saturated with sulfur dioxide (solution obtained by saturating 35 ml of acetic acid with sulfur dioxide and then adding 1.5 g of cupric chloride dihydrate thereto) under ice-cooling with stirring. After 10 minutes, the reaction solution was poured into ice-water, and the precipitates were collected by filtration and washed with water. The precipitates were dissolved in tetrahydrofuran, dried over magnesium sulfate and then concentrated to dryness, to give 3.5 g of the title compound.

Provenance & Evidence