Dichlorido[N′-(3,5-dichloro-2-hydroxybenzylidene)pyridine-4-carbohydrazide-κN](1,10-phenanthroline-κ2 N,N′)cobalt(II) methanol monosolvate

In the title compound, [CoCl2(C13H9Cl2N3O2)2(C12H8N2)]·CH3OH, the CoII atom is octahedrally coordinated by two N atoms from the pyridyl rings of the tridentate N′-(3,5-dichloro-2-hydroxybenzylidene)pyridine-4-carbohydrazide (H2 L) ligand, two N atoms from the 1,10-phenanthroline ligand and two chloride ions. The acylhydrazone groups are not involved into the coordination of the metal ion. In the crystal packing an extended three-dimensional network formed by N—H⋯Cl, N—H⋯O, O—H⋯N, O—H⋯N and O—H⋯Cl hydrogen bonds is observed.


Experimental
Crystal data [CoCl 2 (C 13 H 9 Cl 2 N 3 O 2 ) 2 - (C 12 Table 1 Selected geometric parameters (Å , ).  2.170 (7)   In the field of coordination chemistry, continuing interest in the acylhydrazones transition metal complexes stems from their analytical, catalytic chemistry and as models for metalloenzymes. Acylhydrazone ligands can act as bidentate, tridentate or tetradentate ligands depending on the nature of heterocyclic ring substituents attached to the hydrazone unit.
In (I), there is methanol solvate molecule, and the Co II atom is coordinated by two N atoms from pyridyls of H 2 L and two N atoms from 1,10-phenanthroline and two Cl ions, which form a slightly distorted tetragonal-dipyramid geometry ( Fig. 1). From the bond lengths of (I), we can find the N atoms from 1,10-phenanthroline possess stronger coordinating capability compared to the pyridyls. The acylhydrazone of (I) is a kind of polydentate ligand which contains three heteroatoms. However, the acylhydrazone groups are not involved in the coordination. On the other hand, this phenomenon illustrates the pyridyl N atom of H 2 L has a stronger coordinating capability than the acylhydrazone group.
Also in the structure of 2-pyridinecarbaldehyde isonicotinoylhydrazone and manganese chloride at 2:1 mole ratio no coordination of the acylhydrazone groups with the metal ion was observed (Armstrong et al., 2003). The three-

S2. Experimental
An EtOH solution (30 ml) of 3,5-Dichlorosalicylaldehyde (10 mmol) was added dropwise to the EtOH solution (20 ml) of 4-Pyridinecarboxylic acid hydrazide (10 mmol) with stirring at ca 75\ % C for 3 h. The white precipitates was removed by filtration and recrystallized from EtOH solution. Then a mixture of the ligand (0.5 mmol) and cobalt chloride (0.5 mmol) in MeOH (35 ml) was stirred at ca 65\ % C for 45 min to give the red precipitates. Add 10 ml MeOH solution of 1,10-phenanthroline (0.5 mmol) to the mixture and stirred for 1.5 h. The red precipitate decreased gradually. Then the mixture was filtrated and ether evaporated slowly to afford almost quantitatively red crystals of mononuclear complex at ambient temperature after several days.  The asymmetric unit of (I), showing 30% probability displacement ellipsoids. Carbon-bound H atoms have been omitted.

Data collection
Bruker SMART CCD area-detector diffractometer Radiation source: fine-focus sealed tube Graphite monochromator φ and ω scans Absorption correction: multi-scan (SADABS; Sheldrick, 1996) T min = 0.768, T max = 0.831 17533 measured reflections 7003 independent reflections 3870 reflections with I > 2σ(I) where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max = 0.001 Δρ max = 0.51 e Å −3 Δρ min = −0.57 e Å −3 Absolute structure: Flack (1983), 3259 Friedel pairs Absolute structure parameter: 0.50 (3) Special details Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.