Synthesis, characterization and thermal degradation studies on some oxovanadium(IV) carbodithioates

Abstract

Some oxovanadium(IV) carbodithioates of general formulae [VO(MorphcdtH)2B]SO4, [VO(4-RPipzcdtH)2B]SO4, [VO(4-EtPipzcdt)2B] (Morphcdt = morpholinecarbodithioate, Pipzcdt = piperazinecarbodithioate, R = M, Et and B = nil or Py) have been prepared and characterized by elemental analysis, TG/DSC, FTIR, electrospray mass spectral, conductance, NMR, solution electronic absorption spectral and variable temperature magnetic susceptibility measurement studies. All the complexes exhibit 1:1 electrolytic nature except [VO(4-EtPipzcdt)2B] which is a non electrolyte. Square pyramidal geometry and presence of superexchange interactions through bridging carbodithioate ligands for antiferromagnetic behaviour of complexes [VO(MorphcdtH)2]SO4, [VO(4-RPipzcdtH)2]SO4 and [VO(4-EtPipzcdt)2] have been proposed. Exchange interaction parameter, 2J = −124 to −83 cm−1 has been evaluated. Octahedral geometry for the pyridine adducts of oxovanadium(IV) carbodithioates has been proposed. Some of the complexes have also been screened for their antimicrobial activities against some pathogenic gram-negative bacteria, Escherichia coli, Enterobacter, Pseudomonasaeruginosa, Salmonella typhi, Shigella flexneri and gram-positive Staphylococcus epidermidis and Salmonella typhimurium using twofold serial dilution method. Minimum inhibitory concentration has been determined to fall in the range 31.25–250 μg mL−1.