Di-μ-glutarato-κ4 O 1:O 5-bis[aqua(1,10-phenanthroline-κ2 N,N′)copper(II)]

In the centrosymmetric dinuclear title complex, [Cu2(C5H6O4)2(C12H18N2)2(H2O)2], the CuII atom displays a distorted square-pyramidal coordination environment with the basal plane occupied by two phenanthroline N atoms and two O atoms from different glutarate dianions while a water molecule is located at the apical position. Of the two water H atoms, one is engaged in an intramolecular hydrogen bond with a free oxygen of the dianion whereas the second is engaged in an intermolecular hydrogen bond, building a corrugated layer parallel to (100). These layers are further connected through π–π stacking interactions involving symmetry-related phenanthroline rings [centroid–centroid distance = 3.5599 (17) and 3.5617 (18) Å], building a three dimensionnal network. C—H⋯π interactions involving the phenanthroline ring system are also observed.

Cg1 is the centroid of the N1,C6-C10 ring Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97. Comment For many yeras, there is a growing interest in developing organic-inorganic hybrid materials owing to their intriguing structures, new topologies, and potential applications (Ghosh et al., 2007;Kim et al.,2005). Carboxylic acids have been proved to be versatile functional moieties in generating interesting hybrid materials by interacting with metal ions. The abilities of its anion to metal ions in diverse and unique linking modes can be regarded as a major factor in making the carboxylate function a versatile structure directing moiety.
Metal glutarates are one class of dicarboxylate system which exhibit interesting structural features. Previous investigations have demonstrated that glutaric acid presents interesting behaviors due to its conformational flexibility and coordination diversity (Rather et al., 2003;Zheng et al., 2004;Vaidhyanathan et al., 2004;Girginova et al., 2007). We report here the crystal structure of the title compound.
The title complex, [Cu(C 12 H 18 N 2 )(C 5 H 6 O 4 )(H 2 O)] 2 , is a dinuclear compound organized around inversion center. The Cu II displays a distorted square pyramidal coordination environment (Fig. 1). The basal plane is occupied by two nitrogen  Table 2) building a three dimensional network. The packing is further stabilized by weak C-H···π interaction involving the symmetry related ring A (Table 1).

Experimental
The title complex was prepared by the addition of the stoichiometric amount of CuCl 2 (0.134 g, 1 mmol) to an ethanol solution of glutaric acid (0.264 g, 2 mmol) and 1,10-phenanthroline monohydrate(0.396 g, 2 mmol), the pH was adjusted to ~6 with 0.2 mol.L -1 KOH solution. The resulting solution was stirred for 30 min at room temperature and then filtered.
Blue single crystals were isolated from the solution at room temperature over two weeks.
supplementary materials sup-2 Refinement All H atoms attached to C atoms were fixed geometrically and treated as riding with C-H = 0.93 Å (aromatic) or 0.97 Å (methylene) with U iso (H) = 1.2U eq (C). H atoms of water molecule were located in difference Fourier maps and included in the subsequent refinement using restraints (O-H= 0.88 (1)Å and H···H= 1.50 (2) Å) with U iso (H) = 1.5U eq (O). In the last cycles of refinement, they were treated as riding on their parent O atoms.  Geometric parameters (Å, °)