Binuclear chiral Ni(II) complex of tridentate OON chiral Schiff base ligand, 1-((E)-(((1S,2R)-2-hydroxy-2,3-dihydro-1H-inden-1-yl)imino)methyl)naphthalen-2-ol

Binuclear Ni(II) chelating complex with chiral Schiff base 1-((E)-(((1S,2R)-2-hydroxy-2,3-dihydro-1H-inden-1-yl)imino)methyl)naphthalene-2-ol [Ni2L2] has been synthesized. The structure of [Ni2L2] was elucidated with single-crystal X-ray diffraction, spectroscopic (UV-vis, FTIR, mass) analysis and substantiated with computational (DFT) method. The crystal system of binuclear complex is monoclinic with space group P21/c. The asymmetric unit having two tridentate OON-donor sets are in slightly distorted square-planar geometry around each Ni(II) center. The distortion is due to strong coordination between two Ni(II) ions. The stabilization of complex [Ni2L2] occurs due to noncovalent interactions and hydrogen bonding (C-H horizontal ellipsis C and C-H horizontal ellipsis O), H horizontal ellipsis H, O horizontal ellipsis H, C horizontal ellipsis H, and C-H horizontal ellipsis pi stacking interactions, and van der Waals interactions. DFT optimization, with little acceptable discrepancies, correlate with the X-ray diffraction data as well as TD DFT optimization for electronic transitions of the complex showing acceptable alignment with spectroscopic data. The complex displays appreciable inclination towards DNA-binding with calf-thymus DNA (CT DNA) and the DNA-binding studies were carried out by UV-visible spectroscopy, fluorescence spectroscopy, cyclic voltammetry, viscosity measurements, and CD spectroscopy. The DNA-binding study reveals that the order of binding constant value is in 10(5) M--(1), supporting the effective efficiency of binding and the modes of binding are intercalation and groove.