Self-coupling of diazotised 1-amino-8-hydroxynaphthalene-3,6-disulphonic acid
Abstract
Calcichrome, the product formed by the self-coupling of diazotised 1-amino-8-hydroxynaphthalene-3,6-disulphonic acid, is shown to be 2,8,8′-trihydroxy-1,1′-azonaphthalene-3,6,3′,6′-tetrasulphonic acid (III; R1= H, R2= OH).