Reaction of 1-amino-8-hydroxynaphthalene-3,6-disulphonic acid and its N-acyl and N-s-triazinyl derivatives with cyanuric chloride and 6-substituted 2,4-dichloro-s-triazines. Formation of O-s-triazinyl derivatives and peri-O-? N-s-triazinyl rearrangements

N-Acyl and N-s-triazinyl derivatives of 1-amino-8-hydroxynaphthalene-3,6-disulphonic acid react with cyanuric chloride and with 6-substituted 2,4-dichloro-s-triazines to give the unstable or moderately stable O-s-triazinyl compounds. In the presence of alkali the O-s-triazinyl groups rearrange to the peri-nitrogen atom to give N-s-triazinyl-N-acyl or NN-bis-s-triazinyl derivatives which are hydrolysed to 1-hydroxy-8-s-triazinylaminonaphthalene-3,6-disulphonic acid. 1-(2,4-Dichloro-s-triazinylamino)-8-hydroxynaphthalene-3,6-disulphonic acid undergoes self-condensation at pH 7 to form highly soluble polymeric products which rearrange so that there are hydroxy-groups and NN-bis-s-triazinyl groups present in the molecules.