Hydrochloric Acid → 2-Cyanobenzenesulfonyl Chloride

Participants

Reaction Steps

To a mixed solution of 200 ml of water and 250 ml of concentrated hydrochloric acid was added 25.0 g (212 mmol) of 3-cyanoaniline followed by stirring. An aqueous solution (80 ml) of 15.5 g (223 mmol) of sodium nitrite was added dropwise thereinto at −10° C. The reaction solution was added to acetic acid saturated with sulfur dioxide (prepared by saturating sulfur dioxide in 250 ml of acetic acid followed by adding 2.1 g of cuprous chloride) under ice-cooling and stirring. After 1 hour, the reaction solution was poured onto 500 ml of ice water and extracted with diethyl ether. The extract was washed with a saturated aqueous solution of sodium bicarbonate, water and brine successively, and dried over magnesium sulfate. The solvent was evaporated, a mixed solution of diethyl ether and hexane was added to the residue and the crystals were collected by filtration to give 16.0 g of the title compound.

Provenance & Evidence