Some heterocyclic azo dyes derived from thiazolyl derivatives; synthesis; substituent effects and solvatochromic studies

Spectrochim Acta A Mol Biomol Spectrosc. 2010 Dec;77(5):1084-7. doi: 10.1016/j.saa.2010.08.079.


A series of azo disperse dyes were synthesized by coupling reaction of N,N-diethylaniline, 2-anilinoethanol and N-phenyl-2,2'-iminodiethanol with diazotized aminothiazolyl derivatives as diazo components. These dyes have been prepared in good yields, and were characterized by UV-Vis, FT-IR and 1H NMR spectroscopic techniques. The effects of solvent polarity and various pH on dyes in the visible absorption spectra were evaluated. All dyes exhibit an excellent correlation coefficient (r>0.92) for the linear solvation energy relationship with π* values calculated by Kamlet et al. The influence of the pH on the dyes with electron-donating group implied that these dyes exist in acid-base equilibrium in acidic environment. The effect of substituents of both coupler and diazo component on the color of dyes was investigated as well.

MeSH terms

  • Azo Compounds / chemical synthesis
  • Azo Compounds / chemistry*
  • Azo Compounds / isolation & purification
  • Coloring Agents / chemical synthesis
  • Coloring Agents / chemistry*
  • Coloring Agents / isolation & purification
  • Heterocyclic Compounds / chemical synthesis
  • Heterocyclic Compounds / chemistry*
  • Heterocyclic Compounds / isolation & purification
  • Models, Biological
  • Solvents / chemistry
  • Structure-Activity Relationship
  • Thiazoles / chemical synthesis*
  • Thiazoles / chemistry*
  • Thiazoles / isolation & purification


  • Azo Compounds
  • Coloring Agents
  • Heterocyclic Compounds
  • Solvents
  • Thiazoles