Synthesis, structural, spectral, thermal and antimicrobial studies of palladium(II), platinum(II), ruthenium(III) and iridium(III) complexes derived from N,N,N,N-tetradentate macrocyclic ligand

Palladium(II), platinum(II), ruthenium(III) and iridium(III) complexes of general stoichiometry [PdL]Cl2, [PtL]Cl2, [Ru(L)Cl2]Cl and [Ir(L)Cl2]Cl are synthesized with a tetradentate macrocyclic ligand, derived from 2,6-diaminopyridine with 3-ethyl 2,4-pentanedione. Ligand was characterized on the basis of elemental analyses, IR, mass, and 1H NMR and 13C NMR spectral studies. All the complexes were characterized by elemental analyses, molar conductance measurements, magnetic susceptibility measurements, IR, mass, electronic spectral techniques and thermal studies. The value of magnetic moments indicates that all the complexes are diamagnetic except Ru(III) complex which shows magnetic moments corresponding its one unpaired electron. The macrocyclic ligand and all its metal complexes were also evaluated in vitro against some plant pathogenic fungi and bacteria to assess their biocidal properties.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► Pd(II), Pt(II), Ru(III) and Ir(III) complexes are synthesized with a tetradentate macrocyclic ligand. ► Complexes and ligand were characterized by IR, mass, 1H NMR and 13C NMR, electronic spectral techniques and thermal studies. ► The ligand and all metal complexes were evaluated in vitro against some plant pathogenic fungi and bacteria.