Toluene-o -sulphonyl chlorides

Toluene-o-sulphonyl-chloride,—100 gms. pure toluene are slowly run into 500 gms. of chloro-sulphonic acid cooled to 0° in a pot fitted with good mechanical agitation, the temperature during the addition being kept at 0°—5°. When all the toluene has been added stirring is continued for about 12 hours at the same temperature. The mass is then poured... 

Place 20g (0.105mol) of toluene-o-sulphonyl chloride (Expt 6.41) in a large evaporating dish mounted on a water bath. Add powdered ammonium carbonate cautiously with stirring until the mass is quite hard and solid and the unpleasant odour of the sulphonyl chloride has disappeared. Allow to cool, and extract with cold water to remove the excess of ammonium carbonate. Recrystallise the crude toluene-o-sulphonamide first from hot water (add a little decolourising carbon if it is dark in colour) and then from ethanol. The yield of pure product, m.p. 154°C, is 16 g (89%). 

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