Sodium Hydroxide → HCID 2645656, compound

Participants

Reaction Conditions

Reaction Steps

157.55 g of sodium sulfite (1.25 mol) were dissolved in 725 ml of water and heated to 70° C. At this temperature, 255.08 g of 5-carboxy-2-chlorobenzenesulfonyl chloride were added in portions, the pH (electrode) being kept between 8 and 10 by continuous addition of 320 ml of half-concentrated sodium hydroxide solution (the reaction is slightly exothermic). After the end of the addition, the mixture was subsequently stirred at 70° C. for 2 hours. As soon as the reaction had ended, 5 g of active carbon were added, and after 30 minutes the mixture was filtered hot through a clarifying layer and diluted with 600 ml of water. The solution was allowed to cool to 15°-20° C. and was adjusted to pH 0 using 250 ml of conc. hydrochloric acid, the viscous suspension was stirred in an ice bath for a further 30 minutes and the mixture was then stood well closed in a refrigerator over the weekend. The precipitate was filtered off with suction, washed once with 100 ml of 2N hydrochloric acid and then sucked dry in a stream of air. The substance was sucked dry in vacuo at 50° C.

Provenance & Evidence