Synthesis, Characterization and Analytical Study of New Azo Dye

Abstract

The azo dye ((E)-4-((4-aminophenyl) diazenyl) naphthalen-1-ol) was prepared by diazotization and coupling reaction with 1-naphthol. The azo dye was diagnosed by FT-IR, 1H-NMR, mass spectra and visible spectrometry. The acid and basic properties were studied by the visible absorption spectra of the dye at different pH values and appearance of a clear isobestic point and a high absorption peak at the maximum wavelength (595nm) which is due to the absorption of the negative formula of the dye in the basic medium and an absorption peak at the wavelength (477nm) that is due to the absorption of the proton formula of the dye in the acidic medium. The ionization and protonation constants were calculated and the extent of the indicator within pH (7.4 - 9.4). The effect of the solvents on the visible absorption spectra of the dye was studied, and a clear red shift of the dye spectra was observed in the polar solvents.