Synthesis, characterization, X-ray Crystallography, Photoluminescence property and DNA binding activity of Co(II) and Ni(II) complexes of a pyrazole containing Schiff-base ligand

Two new complexes, [Co(MPAFA)3](ClO4)2, I and [Ni(MPAFA)3](NO3)2.2H2O, II, of a ‘NN’ bidentate Schiff-base ligand, N-(furan-2-ylmethyl)-1-(5-methyl-1H-pyrazol-3-yl)methanimine, (MPAFA) have been synthesized and characterized by various physico-chemical and spectral parameters such as elemental analyses, conductance, IR, UV-Vis, fluorescence spectra etc. In both the complexes, three ligand molecules coordinated to the metal ion to form 1:3 complex. Both I and II are distorted octahedral and cationic in nature and found to behave as 1:2 electrolytes. IR spectra showed that each of the ligand molecule coordinates to the metal centre via the pyrazolyl tertiary nitrogen and the azomethine nitrogen atom. Single crystal X-ray studies have confirmed a CoN6 and NiN6 coordination for I and II, respectively, and also shown that both the complexes are involved in π…π stacking and various hydrogen bonding interactions. Both I and II have been found to possess fluorescence property and displayed potential DNA binding abilities with calf thymus DNA (CT-DNA) via groove mode of binding.