Synthesis, spectroscopic characterization and dyeing performance of novel bis azo dyes derived from benzidine

Alaa Z Omar; Mohamed A El-Rahman; Ezzat A Hamed; Samir K El-Sadany; Mohamed A El-Atawy

doi:10.1038/s41598-023-34660-4

Synthesis, spectroscopic characterization and dyeing performance of novel bis azo dyes derived from benzidine

Sci Rep. 2023 May 15;13(1):7826. doi: 10.1038/s41598-023-34660-4.

Authors

Alaa Z Omar¹, Mohamed A El-Rahman², Ezzat A Hamed², Samir K El-Sadany², Mohamed A El-Atawy^{2

3}

Affiliations

¹ Chemistry Department, Faculty of Science, Alexandria University, P.O. 426, Ibrahemia, Alexandria, 21321, Egypt. Alaazaki@alexu.edu.eg.
² Chemistry Department, Faculty of Science, Alexandria University, P.O. 426, Ibrahemia, Alexandria, 21321, Egypt.
³ Chemistry Department, Faculty of Science, Taibah University, Yanbu, 46423, Saudi Arabia.

Abstract

Benzidine was coupled with ethyl cyanoacetate, and malononitrile, to give azo-hydrazo products which in turn were cyclized by using hydrazine and phenyl hydrazine to give 4,4'-([1,1'-biphenyl]-4,4'-diylbis(hydrazin-2-yl-1-ylidene))bis pyrazole derivatives 5-7. These compounds were identified by various spectral analysis. The examination of 0.1 M NaOH and 0.1 M HCl in DMF revealed that the λ_max of the synthesized dyes are quite sensitive to pH variation and slightly affected by the coupler moieties. Utilizing the dispersion agent DYEWELL-002, polyester fabric (PE-F) was dyed in water. The color strength (K/S), its summation (K/Ssum), dye exhaustion (%E) and reflectance values were measured and discussed. The DFT method estimates the chemical descriptor parameters of the titled dyes, using B3LYP/6-31G(d,p) level to investigate the performance of dyes as well as to postulate a mechanism of dyeing process.