Synthesis and absorption spectra of alkali clearable azo dyes of 5-aminoisophthalic acid

The synthesis of novel, alkali clearable dyestuffs derived from the naphthanilides (5a-h) have been described. 3-carboxy-2-hydroxy naphthanilides (4a-h) were used as coupling agent, and 5-aminoisophthalic acid (3) as diazo component. The dyes were characterized by using FT-IR, 1H and 13C NMR spectroscopy. The absorption maxima of dyes in acidic and basic conditions in various solvents have been evaluated.