117919-03-6Relevant articles and documents
ELECTROCHEMICAL AND CHEMICAL OXIDATION OF SOME AZO DYES
Fasani, Elisa,Soldi, Teresa,Albini, Angelo,Pietra, Silvio
, p. 109 - 114 (2007/10/02)
The oxidation potential of representative azo dyes, viz. a series of N,N-dialkylaminoazo dyes 1 and of tautomeric azonaphthols (2 and 5) has been determined.Anodic oxidation and chemical oxidation have been carried out for some of the dyes.The results are rationalized as involving a single intermediate, the radical cation of the dyes, and its evolution along two main pathways, viz. a) deprotonation whenever possible (from the α position of the N-alkyl group in aminoazo dyes, leading ultimately to N-dealkylation; fromthe naphthols to eventually yield a C-C-coupled dimer) and b) heterolytic cleavage to an aryl radical and a diazonium cation, the latter trapped under favourable conditions to yield a bisazodye.