Study of Environment and pH Effects on the Spectral Behavior of Arylazobenzylidene Dyes

In this study, four arylazobenzylidene dyes (ad) were synthesized with excellent yields in two steps using Knoevenagel condensation and azocoupling reactions. Absorption spectra of these dyes with different substituents were investigated in organic solvents as a function of solvent polarity. The spectral features of synthesized arylazobenzylidene dyes were described according to azohydrazone tautomerism as well as the solvatochromic characteristic of the approved tautomer. The nature and degree of solutesolvent interactions were illustrated using KamletTaft multiparameter polarity scales. The effects of acidbase on the UVvisible absorption spectra of the dyes were reported. In addition, different absorption characteristics were observed for these dyes in pure diethanolamine.