Date Published: May 01, 2009
Publisher: International Union of Crystallography
Author(s): Hadi Kargar, Reza Kia, Arezoo Jamshidvand, Hoong-Kun Fun.
In the title complex, [Ni(C26H26N2O4)]·2H2O, the NiII ion, lying on a twofold crystallographic rotation axis, has a square-planar geometry, being coordinated by the N2O2 unit of the tetradentate Schiff base ligand. The asymmetric unit of the title compound comprises one-half of the complex molecule and one of the water molecules of crystallization. The water H atoms form bifurcated O—H⋯(O,O) hydrogen bonds with the O atoms of the phenolato and ethoxy groups with R12(5) and R12(6) ring motifs. The dihedral angle between the central benzene ring and the two outer benzene rings are 4.07 (11) and 3.99 (12)°. The dihedral angle between the two O–Ni–N coordination planes is only 0.77 (11)°. In the crystal structure, the molecules are linked together into extended chains along the c axis by intermolecular O—H⋯O and C—H⋯O interactions. An interesting feature of the crystal structure is a short intermolecular C ⋯ C [3.355 (3) Å] contact, which is shorter than the sum of the van der Waals radii. The crystal structure may be further stabilized by intermolecular π–π interactions [centroid–centroid distances in the range 3.5758 (13)–3.6337 (13) Å].
For bond-length data, see Allen et al. (1987 ▶). For related structures see, for example: Clark et al. (1968 ▶, 1969 ▶, 1970 ▶). For the applications and bioactivity of Schiff base complexes see, for example: Elmali et al. (2000 ▶); Blower (1998 ▶); Granovski et al. (1993 ▶); Li & Chang, (1991 ▶); Shahrokhian et al. (2000 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶).