3-Nitrobenzenesulfonyl chloride → 8-(3-m-Nitrobenzenesulfonamido-p-toluenesulfonamido)-1,3,5-naphthalenetrisulfonic acid

Participants

Reaction Steps

To a stirred solution of 2.0 g of 8-(3-amino-p-toluenesulfonamido)-1,3,5-naphthalenetrisulfonic acid trisodium salt and 342 mg of anhydrous sodium carbonate in 10 ml of water is added 1.5 g of m-nitrobenzenesulfonyl chloride. The mixture is stirred for 16 hours. An additional 170 mg of anhydrous sodum carbonate is added followed by 750 mg of m-nitrobenzenesulfonyl chloride and the mixture is stirred for an additional 16 hours. The reaction mixture is evaporated and the residue dissolved in hot water. A product is precipitated on the addition of absolute ethanol. The product is collected, washed with ethanol and ether and dried. Additional product is collected from the filtrate and is washed and dried as above. The above fractions of product are combined and dissolved in water, then 2.5 ml of 5 N sodium hydroxide is added and the mixture is stirred for 30 minutes. The mixture is acidified with glacial acetic acid and evaporated. The residue is dissolved in hot water and precipitated with ethanol. The product is collected and washed twice with ethanol and ether and dried to yield 700 mg of 8-(3-m-nitrobenzenesulfonamido-p-toluenesulfonamido)-1,3,5-naphthalenetrisulfonic acid, trisodium salt.

Provenance & Evidence