Synthesis, structural characterization and biological studies of Ni(II), Cu(II) and Fe(III) complexes of hydrazone derived from 2-(2-(2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-ylidene)hydrazinyl)benzoic acid

Abstract

A new ligand, 2-(2-(2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-ylidene)hydrazinyl)benzoic acid has been synthesised by coupling diazotised 2-amino benzoic acid with Meldrum’s acid (Japp-Klingemann reaction). It was characterised by micro-analytical, spectral and single crystal X-ray diffraction studies. The hydrazone molecule formed is stabilised by three- centred resonance assisted hydrogen bonding and eventually giving a discrete dimer associated via intermolecular hydrogen bonding in the solid state. Coordination complexes with Ni(II), Cu(II) and Fe(III) were prepared and characterised using microanalytical, spectral and single crystal X-ray diffraction studies. The SCXRD analysis of the Ni(II) complex confirmed the azo-enol form of the ligand in the complex. The anomalous magnetic behaviour of the Fe(III) complex is interpreted using Mössbauer spectral analysis. Antimicrobial screening of the compounds was performed using selected bacterial and fungal pathogens.