Synthesis, spectroscopic and DNA binding ability of Co~Ⅱ, Ni~Ⅱ, Cu~Ⅱ and Zn~Ⅱ complexes of Schiff base ligand (E)-1-(((1H-benzo[d]imidazol-2-yl) methylimino)methyl)naphthalen-2-ol. X-ray crystal structure determination of cobalt (Ⅱ) complex

摘要

A novel Schiff base ligand, (E)-1-(((1H-benzo[d]imidazol-2-yl)methylimino)methyl)naphthalen-2-ol (HL), has been designed and synthesized in addition to its metal chelates [Co(L)2]-12H20, [Ni(L)Cl-(H20)2].5H20, [Cu(L)Cl] and [Zn(L)(CH3COO)]. The structures of the isolated compounds have been confirmed and identified by means of different spectral and physicochemical techniques including CHN analysis, ~1H & ~(13)C NMR, mass spec¬ tral analysis, molar conductivity measurement, UV-Vis, infrared, magnetic moment in addition to TGA technique. The infrared spectral results ascertained that the ligand acts as monobasic tridentate binding to the metal centers via deprotonated hydroxyl oxygen, azomethine and imidazole nitrogen atoms. The UV-Vis, magnetic susceptibil¬ ity and molar conductivity data implied octahedral geometry for Co(II) & Ni(II) complexes, tetrahedral for Zn(II) complex and square planar for Cu(II) complex. X-ray structural analysis of Co(Ⅱ) complex 1 has been reported and discussed. Moreover, the type of interaction between the ligand & its complexes towards salmon sperm DNA (SS-DNA) has been examined by the measurement of absorption spectra and viscosity which confirmed that the ligand and its complexes interact with DNA via intercalation interaction as concluded from the values of binding constants (Kb).