4-Methoxybenzenesulfonyl chloride → 4-Methoxybenzenesulfonamide

Participants

Reaction Conditions

Reaction Steps

With stirring 96.47 g (0.467 m) of the 4-methoxybenzenesulfonyl chloride obtained in part A above was slowly added to a slurry of 175.0 ml of concentrated ammonium hydroxide and 175.0 g of ice keeping the temperature under -5° C. during the addition. Slowly the resulting mixture was heated to approximately 70° C. over approximately two and one half hours. The resulting slurry was cooled and maintained at approximately 10° C. for about forty minutes. The solid was collected by filtration, washed three times with 50.0 ml of ice water and dried on the filter to obtain 97.37 g of water-wet 4-methoxybenzenesulfonamide. This product was suspended in 664.0 ml of water and 22.0 ml of 50 percent aqueous sodium hydroxide and 3.75 g of decolorizing carbon was added. After approximately forty-five minutes, the carbon was collected by filtration and washed twice with 50.0 ml of water. The filtrate and 50.0 ml or rinse water was adjusted to approximately pH 3 with the addition of approximately 33.0 ml of concentrated hydrochloric acid. The resulting slurry was cooled to approximately 5° C., stirred approximately two hours and the solid was collected by filtration, washed three times each with 50.0 ml of ice water and dried in vacuo to obtain 70.93 g of 4-methoxybenzenesulfonamide, a shiny white solid which melted at 111.5°-112.50° C. The nuclear magnetic resonance spectrum was concordant with the assisgned structure.

Provenance & Evidence