Synthesis, solvatochromism, and theoretical study of 4-(2-hydroxy-5-(phenyldiazenyl)benzylideneamino)benzenesulfonamide

The azo dyes are the largest class of industrial synthesized organic dyes due to their various applications, such as dyeing textile fiber, laser, liquid crystalline displays, electro-optical devices and ink-jet printers [1]. They are also known to have a broad range of antibacterial, antifungal, antitumor and antioxidant activities [2-4].The sulfanilamide azo-dyes were designed and characterized by elemental analysis, mass, IR, UV–Vis and NMR spectroscopy. The UV–Vis spectra of dyes derivatives were determined in different acidities for evaluating factors affected intramolecular hydrogen bonding, enol–keto tautomerism, dipole moment and solvatochromism behavior. The solvatochromism behaviors of dyes were evaluated in solvents with different polarities also their cyclic voltammetry were carried out in DMSO as a solvent. The optimum molecular geometries, molecular electrostatic potential, Nucleus-Independent Chemical Shift, frontier molecular orbitals, infrared and electronic absorption spectra of products were investigated with theoretical methods. Results of theoretical calculations have good agreement with the experimental values.