Synthesis and Characterization of New Schiff Base Containing 1,2,4-Triazole-3-thione Moiety and Its Complexes with Some Transition Metal Ions: Spectroscopic and Computational Studies

The divalent transition metal ions Co, Ni, and Cu coordination compounds with unusual bidentate mixed Schiff base-based 1,2,4-triazole-3-thione ligand in a protonated specific coordination stoichiometry and structures forms were synthesized. The structural composition of the ligand 5-(1-naphthylmethyl)-4-{(Z)-[(2E)-3-phenyl-2-propen-1-ylidene]amino}-2,4-dihydro-3H-1,2,4-triazole-3-thione (LH) was fully identified by H-1 and C-13 NMR, FTIR, UV-Vis, mass spectrometry as well elemental analysis. The UV-Vis, FTIR spectroscopy, magnetic susceptibility measurements, molar conductance, flame atomic absorption, and elemental analysis (CHNS) techniques were used to characterize the synthesized complexes. Three complexes of Ni(II), Co(II), and Cu(II), in addition to the ligand LH, were the subject of computational investigations. Benchmark analyses were carried out to determine the best degree of calculation for the complexes under the study. The B3LYP approach was chosen as the computation method. The B3LYP/6-31G (d,p) (LANL2DZ) was the best calculation rank. IR spectra and structural studies were carried out. Furthermore, a thorough investigation and examination of biological characteristics were conducted. Complex (Cu) was determined to be the most excellent choice for biological applications based on calculation findings.