Phenyl isocyanate → 4,4′-Bis(3-phenylureido)-2,2′-stilbenedisulfonic acid disodium salt

Participants

Reaction Steps

(E)-6,6′-(Ethene-1,2-diyl)bis(3-aminobenzenesulfonic acid) (18.5 g, 0.05 mol) was dissolved in water (800 ml) by adjusting to pH 7 with 2N sodium hydroxide. Phenyl isocyanate (11.9 g, 0.10 mol) was added over a period of 90 minutes then stirred overnight. Further phenyl isocyanate (0.6 g, 0.005 mol) was added with a second overnight stir. The resultant suspended solid was filtered off, re-suspended in acetone, filtered off and dried for 24 h at 40° C. to give the title compound as a beige solid (31.7 g, 78%); C28H22N4Na2O8S2 requires C, 51.5%, N, 8.6%. found C, 44.8%, N, 6.9%, sample strength determined as 80% based on N content.

Provenance & Evidence