Efficient green synthesis and characterization of bridged nitrogen heterocyclic systems and application on polyester fabric with quinoxaline and isoxazole nuclei

Purpose This study aims to explore a rapid, less expensive, clean and environmentally friendly approach to the synthesis of disperse dyes based on 4-substituted benzenesulfonamide derivatives and evaluate their uses as colorants for dying and printing on polyester fabric. Design/methodology/approach The disperse dyes were created by dissolving solution of the diazonium salt of a 4-substituted benzenesulfonamide derivative 1 reaction with N’-(2-bromobenzylidene)-2-cyanoacetohydrazide in 25 mL of ethanol was added to the diazonium salt. The reaction mixture was then stirred in an ice bath for 2 h. Thus, developing less hazardous synthetic methods for organic reactions is one of the objectives in current research. The chemical structure of the produced dye was studied using elemental analysis, Fourier-transform infrared spectroscopy, 1H NMR and 13C NMR spectroscopic analytical methods. Quantum chemical calculations were performed using the time-dependent density function theory (TD-DFT)-B3LYP method and a 6-311G(d) basis set. Findings By varying the dyeing parameters, such as pH (2–8), shade (2–6%), duration (10–30 min) and temperature (100–130 °C), a comparative examination of various colorimetric and color strength (K/S) properties of polyester fabric dye using two new dispersion dyes was carried out. Higher K/S ratios were attained by polyester fabrics treated with dispersed dyes after longer dyeing times) and higher temperatures. The resulting hues were reddish-brown, yellowish-brown, beige and dark brown. According to TD-DFT calculation, dye 2 exhibits more energy changes than dye 3, indicating strong binding interactions. However, because of its higher hardness and electronegativity, dye 3 is more stable. In contrast to dye 3, dye 2 exhibits increased reactivity due to its greater softness and lesser hardness. These variations draw attention to the unique qualities of the two colors. It was also noticed that dye 2 is more efficient than dye 3 in the printing ink characterization according to their results based on lightfastness, washing, alkali respiration and crock fastness. Originality/value The produced disperse dyes (2 and 3) have the potential to be promising colorants in a variety of applications, such as coloring and printing. Synthetic dyes are often a great choice for printing and dyeing polyester textiles. They also provide a workable way to provide polyester textiles with a range of hues.