The Ready Desulphonation of Two Simple Azo Dye Acids

Abstract
Under normal drying conditions, the free acids of C.I. Acid Red 88 and 27 have been shown to undergo partial desulphonation in the naphthionic acid portion of the molecule, with formation of 1‐naphthaleneazo‐2‐naphthol and 1‐naphthaleneazo‐2‐naphthol‐3,6‐disulphonic acid, respectively. This must be taken into account in preparing pure dye acids for dyeing studies. The reason for the apparent stability towards desulphonation of the intermediate member of the series, C.I. Acid Red 13, is not obvious.

This publication has 3 references indexed in Scilit: