Synthesis, characterization, and multifunctional applications of novel metal complexes based on thiazolylazo dye

Abstract

AbstractHerein, a novel ligand, namely, N,N‐dimethyl‐4‐((4‐(pyridin‐2‐yl)thiazol‐2‐yl)diazenyl)aniline, and its solid Mn (II), Co (II), Ni (II), and Cu (II) complexes have been synthesized and characterized. The photophysical properties of the thiazolyl azo ligand, L, have been investigated in various solvents of different polarities. The absorption and fluorescence maxima of the ligand show a strong dependence on the solvent polarity. The metal ions sensing response to Mn (II), Co (II), Ni (II), and Cu (II) ions were also investigated in ethanolic solutions. The novel solid complexes of hexacoordinate Mn (II), Co (II), Ni (II), and Cu (II) of the ligand have the molar ratio 2:1 (M:L) and general chemical formula [M2(L)(H2O)4Cl4]·nH2O. The presence of metal–metal interaction was proved by the low magnetic moment values μeff of metal complexes. The UV–Vis spectra of the ligand and its metal complexes displayed bands characteristic to different types of transitions inside the molecules. The metal complexes show additional absorption bands of very low intensity around 650–690 nm attributed to d–d transitions within the metal ion indicating octahedral geometry. The geometry of the ligand and its complexes was also theoretically confirmed using the DMOL3 program and density functional theory (DFT). The free ligand and its metal complexes have been studied for their DNA‐binding properties using steady‐state absorption and emission techniques. They demonstrated successful binding properties against CT‐DNA in an intercalative mode. Additionally, the ligand and its metal complexes have also been successfully applied to polyester fabrics as disperse dyes. Multifunctional properties such as color representation, colorimetric data (L*, a*, b*, C*, h*, K/S), and fastness properties of the dyed samples have been discussed and evaluated in detail. These dyes have proven their efficiency in dyeing polyester fabrics, as they give satisfactory results in fastness properties, colorimetric data. Moreover, the antioxidant and antitumor activities for the synthesized compounds were evaluated.