{6,6′-Dimethoxy-2,2′-[2,2-dimethylpropane-1,3-diylbis(nitrilomethylidyne)]diphenolato}nickel(II) 1.78-hydrate

Abstract

In the title complex, [Ni(C21H24N2O4)]·1.78H2O, the NiII ion has a slightly distorted planar geometry, coordinated by the two N and two O atoms of the tetra­dentate Schiff base ligand, with a mean deviation of 0.272 Å from the NiN2O2 plane. The N and O donor atoms are mutually cis. The dihedral angle between two benzene rings of the ligand is 38.86 (8)°. There are also three solvent water mol­ecules, two of which lie across different crystallographic twofold rotation axes; one of these is partially occupied with a refined occupancy factor of 0.570 (7). The water mol­ecules are linked together as tetra­mers in R 2 2(8) ring motifs, which also connect two neighbouring mol­ecules of the complex through a network of O—H⋯O hydrogen bonds. The crystal structure is further stabilized by inter­molecular C—H⋯O and C—H⋯π inter­actions, which link neighbouring mol­ecules into extended chains along the b axis. Other inter­esting features of the crystal structure are the short inter­molecular C⋯C [3.204 (3)–3.365 (3) Å] and the C⋯O [3.199 (2)–3.205 (2) Å] contacts which are shorter than the sum of the van der Waals radii of these atoms.