New complexes of Co(II), Ni(II), Cu(II) with Schiff base N,N’-bis-(3-methoxy-saliciliden)-3,3’-dimethylbenzidine

The new N,N’-bis-(3-methoxy-saliciliden)-3,3’-dimetilbenzidine (H2L) Schiff base and complexes with Co(II), Ni(II) and Cu(II) of type [M(HL)Cl(H2O)] (M=Co(II), Cu(II)) [M2L(H2O)4]X2 (M=Co(II), X=ClO4 and M=Cu(II), X=NO3) and [M2L(CH3COO)2] (M=Co(II), Ni(II), Cu(II)) were synthesised. The ligand and complexes were characterized by elemental analysis, conductibility measurements, magnetic moments at room temperature, IR, NMR, UV-VIS-NIR, EPR spectra and thermogravimetric analysis. A molar ratio of 1:1 or 1:2 between ligand and metal was determined from the elemental analysis. Except for perchlorate complex that behave as electrolyte, the rest of complexes are non-electrolytes. The spectral data suggest a tetrahedral, pseudo-tetrahedral or square-planar stereochemistry respectively, data confirmed by magnetic behaviour of complexes. The antimicrobial tests indicate a fungicide effect both for ligand and complexes

Template synthesis, characterization and antimicrobial activity of some new complexes with isonicotinoyl hydrazone ligands

Complexes of Cu(II), Ni(II), Co(II) with the 9-anthraldehyde iso-nicotinoyl hydrazone ligand (HL1) and the 3,5-di-tert-butyl-4-hydroxy-benzaldehyde isonicotinoyl hydrazone ligand (H2L2) were synthesized by the template method. The complexes were characterized by analytical analysis, IR, UV-Vis and ESR spectroscopy, magnetic measurements, conductometry and thermal analysis and the two ligands by 1H-NMR spectroscopy. From the elemental analysis, 1:2 (metal:ligand) stoichiometry for the complexes of Cu(II), Ni(II) with the ligands HL1 and H2L2 and 1:1 (metal:ligand) stoichiometry for the complex of Co(II) with the ligand HL1 are proposed. The molar conductance data showed that the complexes are non-electrolytes. The magnetic susceptibility results coupled with the electronic and ESR spectra suggested a distorted octahedral geometry for the complexes Ni(II)/HL1, Ni(II)/H2L2 and Cu(II)/H2L2, a tetrahedral stereochemistry for the complex Cu/HL1 and a square-planar geometry for the complex Co/HL1. The IR spectra demonstrated the bidentate coordination of the ligands HL1 and H2L2 by the O=C amide oxygen and the azomethine nitrogen, as well as monodentate coordination of the ligand HL1 by the azomethine nitrogen in the Cu(II)complex. The antibacterial activity of the ligands and their metallic complexes were tested against Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae

Synthesis and characterization of new complexes of some divalent transition metals with N-isonicotinamido-4-chlorobenzalaldimine

New complexes of N-isonicotinamido-4-chlorobenzalaldimine (INHCBA) with Cu(II), Co(II) and Cd(II), having formula of the type [M(INHCBA)(ac)2]·xH2O (M = Cu2+, x = 1, M = Co2+, x = 2, M = Cd2+, x = 0, ac = CH3COO-), and with Cu(II), Mn(II) and Zn(II), having formula of the type [M(INHCBA)2(H2O)2]SO4·xH2O (M = Cu2+, Mn2+, x = 2 and Zn2+ x = 2.5) were synthesized and characterized by analytical and physico-chemical techniques, i.e., elemental analyses, IR, UV–Vis–NIR and EPR spectroscopy as well as thermal analysis and the determination of the molar conductivity and magnetic moments. The thermal behaviour of complexes was studied by ther­mogravimetry (TG), differential thermal analysis (DTA) and differential scan­ning calorimetry (DSC). The ligand behaves as bidentate NO, being coordi­nated through the azomethine nitrogen and carbonylic oxygen. The heats of decomposition, ΔH, associated with the exothermal effects, were also deter­mined