Structure and Spectroscopic Studies of Bis Azo Compounds with S/SO2 Bridges and Containing Cyclic-1,3-Dicarbonyl Groups

A series of new bis azo dyes were synthesized starting from aromatic diamine with S/SO2 bridges and cyclic-1,3-dicarbonyl groups; contain active methylene group, namely; 3,3-dimethyl-1,5-cyclohexadione (dimedone), 1,3-cyclohexadione 2,2-dimethyl-1,3-dioxane-4,6-dione to give 1-6. Whether the reaction is complete purity compounds checked TLC. The structure newly synthezed was investigated by using, FT-IR, 1HNMR, LC–MS/MS UV–Visible spectrophotometric methods, CH3OH used in LC-MS/MS experiments, molecular masses seen as M M+1 protonated spectrum. In UV-Vis spectra these compounds, solvent effect using different solvents also acid-base adding HCl or KOH medium investigated. tautomeric equilibrium forms (enol-imine O-H….N, keto-amine O….H-N forms) according electronic spectrum recorded chloroform, dimethylformamide (DMF), acetic acid, methanol solvents. results UV-visible 1H-NMR indicated that acid found hydrazo tautomer (keto-amine proposed forms.