[2-Hydroxy-N′-(4-oxo-4-phenylbutan-2-ylidene)benzohydrazidato(2−)]pyridinecopper(II)

The mononuclear title complex, [Cu(C17H14N2O3)(C5H5N)], was synthesized by the reaction of CuCl2·2H2O with N-(4-oxo-4-phenylbutan-2-ylidene)benzohydrazide (H2 L). The central CuII atom exhibits a distorted square-planar coordination geometry, defined by two O atoms, one N atom from the ligand and one pyridine N atom with Cu—N distances of 1.874 (4) and 1.963 (4) Å, while the Cu—O distances are 1.857 (3) and 1.890 (3) Å. An intramolecular O—H⋯N interaction occurs.


Experimental
Crystal data [Cu(C 17 Table 1 Hydrogen-bond geometry (Å , ). sites of numerous metallobiomolecules (Singh, et al., 2007). They serve as models for biological important species and find applications in biomimetic catalytic reactions. Chelating ligands containing N and O donor atoms show broad biological activity and are of special interest because of the variety of ways in which they are bonded to metal ions. It is known that the existence of metal ions bonded to biologically active compounds may enhance their activities (Canpolat, et al., 2004;Yildiz, et al., 2004). Therefore, it is an important study to design and synthesis of new multidentate ligands cotaining N and O atoms and apply to synthesize complexes.
The asymmetric unit is composed of one mononuclear complex, (Fig.1). The central Cu II atom exhibits a distorted square-plannar coordination geometry, defined by two O atoms, one N atom from the ligand molecule and one N atom of the pyridine molecule with Cu-N distances of 1.874 (4) and 1.963 (4) Å while Cu-O distances are 1.857 (3) and 1.890 (3) Å respectively. The Cu-N and Cu-O distances are comparable to those found in other crystallographically characterized Cu II complex (Shen, et al. 1997). The crystal structure of the title compound is stabilized by one intramolecular O-H···N interactions with average H···N distances 1.78Å and O-H···N angle 146.3°.

Experimental
All reagents and solvents were used as obtained commercially without further purification. CuCl 2 .2H 2 O (0.170 mg, 0.1 mmol) was dissolved in 6 ml deionized water, giving a transparent solution, and 1 mL pyridine solution dissolved with L (28.2 mg, 0.1 mmol) was dropwised for 0.5 h. After stirring for 8 h, the solution was filtered. Black single crystals of the title compound were obtained from the filtrate after 3 weeks. Analysis calculated (%): C,60.47;H,4.38;N,9.62%;Found: C,60.15;H,4.59;N,9.49%.

Refinement
H atoms bonded to C atoms were placed geometrically and treated as riding, with C-H distances 0.93-0.96Å and U iso (H) = 1.2U eq (C) for the CH while U iso (H) = 1.5U eq (C) for the CH 3 groups. The hydroxyl H atoms were located from difference maps and refined with the O-H distances restrained to 0.82 Å and U iso (H) = 1.5U eq (O).
supplementary materials sup-2 Figures Fig. 1. The molecular structure of the title compound, showing 30% probability displacement ellipsoids.