Studies on reactions of some ruthenium sulfoxide bipyridyl complexes with 1,4-bis(salicylidene)phenylenediamine ligand used as spacer

A dinucleating spacer 1,4-bis(salicylidene)phenylenediamine (SALPHEN) derived from 1,4-phenylenediamine and salicylaldehyde has been synthesized and characterized. The ruthenium(II) sulfoxide derivative of 2,2'-bipyridine or 1,10-phenanthroline on reaction with this ligand resulted in the formation of eight dinuclear complexes, which were characterized by elemental analyses, conductivity measurements, magnetic susceptibility, FT-IR, fast atom bombardment-mass spectra, electronic spectroscopy, H-1-NMR, C-13{H-1}-NMR, and D-2-NMR spectra (HETCOR). The prepared complexes have two different formulations, [{trans-RuCl2(so)(N-N')}(2)(mu-SALPHEN)] and [{cis-RuCl2(so)(N-N')}(2)(mu-SALPHEN)], where so = dimethyl sulfoxide (DMSO)/tetramethylene sulfoxide (TMSO), N-N' = 2,2'-bipyridine/1,10-phenanthroline, and SALPHEN = 1,4-bis(salicylidene)phenylenediamine. Two moles of ruthenium sulfoxide bipyridine precursor were coordinated to the bidentate SALPHEN through nitrogen. All the complexes possess antibacterial activity against Escherichia coli in comparison to Chloramphenicol.