Abstract
BackgroundA series of some novel arylazo pyridone dyes was synthesized from the corresponding diazonium salt and 6-hydroxy-4-phenyl-3-cyano-2-pyridone using a classical reaction for the synthesis of the azo compounds.ResultsThe structure of the dyes was confirmed by UV-vis, FT-IR, 1H NMR and 13C NMR spectroscopic techniques and elemental analysis. The solvatochromic behavior of the dyes was evaluated with respect to their visible absorption properties in various solvents.ConclusionsThe azo-hydrazone tautomeric equilibration was found to depend on the substituents as well as on the solvent. The geometry data of the investigated dyes were obtained using DFT quantum-chemical calculations. The obtained calculational results are in very good agreement with the experimental data.
Highlights
A series of some novel arylazo pyridone dyes was synthesized from the corresponding diazonium salt and 6-hydroxy-4-phenyl-3-cyano-2-pyridone using a classical reaction for the synthesis of the azo compounds
The obtained calculational results are in very good agreement with the experimental data
The success of azo colorants is due to the simplicity of their synthesis by diazotization and azo coupling, the almost innumerable possibilities presented by variation of the diazo compound and coupling component, the generally high molar extinction coefficient and the medium to high light and wet fastness properties [5]
Summary
The results showed that the solvent effect on UV-vis absorption spectra of the investigated arylazo pyridone dyes is very complex and strongly depends on the nature of the substituent on the arylazo component. The introduction of electron-donating substituents into the arylazo ring results in strong bathochromic shifts in all solvents. These solvatochromic properties are evident for the hydrazone tautomeric form. Additional file 1 includes the experimental procedures and the results of the physico–chemical characterization of the investigated compounds [5,14]. Additional file 6: 13C NMR (50 MHz, DMSO-d6) spectra of 5-(4nitrophenylazo)-6-hydroxy-4-phenyl-3-cyano-2-pyridoine (12). Additional file 7: IR spectra of 5-(4-nitrophenylazo)-6-hydroxy-4phenyl-3-cyano-2-pyridoine (12)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
