STRUCTURAL AND SOLVATOCHROMIC PROPERTIES OF SOME AZOQUINOLINE DYES

The azo-hydrazone tautomerism in azo compounds has been known for many years and wasreviewed several times [1,2]. The presence of azo-hydrazone tautomerism in thesecompounds influence considerably in their unique photophysical properties, which is in turnstrongly influenced by several factors including temperature, substituents structure , solventpolarity and pH [3,4]. Azo-hydrazone tautomerism has been studied by various opticaltechniques, including electronic method. Due to the characteristic differences between theoptical spectra of the dyes in azo and hydrazone forms, azo-hydrazone tautomeric behaviorcan be investigated from the electronic spectra.