[2-(2-Carboxyphenyl)benzoato]bis(1,10-phenanthroline)zinc(II) 2-(2-carboxyphenyl)benzoate monohydrate

In the title compound, [Zn(C14H9O4)(C12H8N2)2](C14H9O4)·H2O, the ZnII atom of the complex cation is six-coordinated in an octahedral geometry by four N atoms from two 1,10-phenanthroline ligands and two O atoms of a carboxylate group from a singly deprotonated diphenic acid. The phenanthroline and carboxylate ligands act as chelating ligands. The dihedral angles between the two benzene rings in the deprotonated diphenic acid groups are 81.05 (2) (ligand) and 89.10 (2)° (anion). O—H⋯O and C—H⋯O hydrogen bonds link the components into a three-dimensional network.


Experimental
Crystal data [Zn(C 14
The asymmetric unit of the title compound consists of a [Zn(C 12 H 8 N 2 ) 2 (C 14 H 9 O 4 )] + complex cation, one singly deprotonated diphenic acid anion (C 14 H 9 O 4 -) and one water molecule (Fig. 1). In the complex cation, the Zn II atom is sixcoordinated in an octahedral geometry by four N atoms from two 1,10-phenanthroline ligands and two O atoms of a carboxylate group from a diphenic acid, with Zn-N distances of 2.128 (3) Table 1). The phenanthroline and diphenic acid act as chelating ligands (Table 1 and Fig.1). The dihedral angle between the two benzene rings in diphenic acid is ca 81.05 (2)° (cation) and 89.10 (2)° (anion).
Intermolecular O-H···O and C-H···O hydrogen bonds (Table 2) link complex cations, anions and water molecules to form a three-dimensional network (Fig. 2).

S2. Experimental
A mixture of diphenic acid (0.0484 g, 0.2 mmol), phenanthroline (0.04 g, 0.2 mmol), Zn(NO 3 ) 2 .6H 2 O (0.1 mmol) and NaOH (0.012 g, 0.3 mmol) with a molar ratio of 2/2/1/3 in H 2 O-CH 3 CH 2 OH (v/v 4/1) (15 ml) was sealed in a Teflonlined stainless steel Parr bomb. The bomb was heated to 433 K for 72 h and then cooled to room temperature at 5 K h -1 . A large amount of yellow crystals formed, which were collected by filtration, washed with water, and dried in air.

S3. Refinement
The water H atoms were located in a difference map and their positional parameters were refined with O-H distances  The asymmetric unit of the title compound, showing 30% probability displacement ellipsoids. H atoms have been omitted for clarity.

Figure 2
The crystal packing of the title compound, viewed down the a axis. Hydrogen bonds are shown as dashed lines.

[2-(2-Carboxyphenyl)benzoato]bis(1,10-phenanthroline)zinc(II) 2-(2-carboxyphenyl)benzoate monohydrate
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.