catena-Poly[[[aqua(2,2′-bipyridine-κ2 N,N′)zinc]-μ-furan-2,5-dicarboxylato-κ2 O 2:O 5] dihydrate]

In the title hydrated coordination polymer, {[Zn(C6H2O5)(C10H8N2)(H2O)]·2H2O}n, an infinite [1-10] chain is formed by the linking of [Zn(C10H8N2)(H2O)]2+ entities by bridging, monodentate furan-2,5-dicarboxylate dianionic linkers. The Zn2+ coordination geometry is a trigonal bipyramid, with one N atom (from 2,2′-bipyridine) and one O atom (from the bridging dianion) in the axial positions. For each ZnII atom, the dihedral angle between the furan ring of its coordinated bridging ligand and its coordinated bipyridine ring system is 87.19 (8)°. O—H⋯O hydrogen bonds involving both the coordinated and uncoordinated water molecules generate a layer motif parallel to (001).

In the title hydrated coordination polymer, {[Zn(C 6 H 2 O 5 )-(C 10 H 8 N 2 )(H 2 O)]Á2H 2 O} n , an infinite [110] chain is formed by the linking of [Zn(C 10 H 8 N 2 )(H 2 O)] 2+ entities by bridging, monodentate furan-2,5-dicarboxylate dianionic linkers. The Zn 2+ coordination geometry is a trigonal bipyramid, with one N atom (from 2,2 0 -bipyridine) and one O atom (from the bridging dianion) in the axial positions. For each Zn II atom, the dihedral angle between the furan ring of its coordinated bridging ligand and its coordinated bipyridine ring system is 87.19 (8) . O-HÁ Á ÁO hydrogen bonds involving both the coordinated and uncoordinated water molecules generate a layer motif parallel to (001).

Related literature
For a related structure, see : Li, et al. (2012).
The asymmetric unit of (I) is consisted of one Zn(II) cation, one furan-2,5-dicarboxylate anion, one 2,2′-bipyridine and three waters involving in one coordinated waters and two structural water ( Fig.1). Zn cation is coordinated by two N atoms of 2,2′-bipyridine, one water O atoms and two carboxylate O atoms, exhibiting a triangle bipyramid geometry (Table 1) with one O atoms of furan-2,5-dicarboxylate and one nitrogen atom of 2,2′-bipyridine in the axial positions. The adjacent Zn cations are connected by the furan-2,5-dicarboxylate to infinite chain (Fig.2). O water -H···O hydrogen bonds (Table 2) help to consolidate the structure.

Refinement
Water H atoms were located in a difference Fourier map and refined with O-H = 0.87 (2) Å and U iso (H) = 1.2Ueq(O).
The carbon H-atoms were placed in calculated positions (C-H (furan and pyridine ring) = 0.93 Å) and were included in the refinement in the riding-model approximation, with U iso (H) = 1.2Ueq(C).  The unit cell of (I), showing displacement ellipsoids at the 50% probability level. [Symmetry code: (i) 1 + x, -1 + y, z.]

Figure 2
The polyhedral plot of (I), displaying the infinite chain formed by linking the adjacent Zn cations with furan-2,5-dicarboxylate.  The ball-stick packing diagram of (I). The adjacent chains are holded together by the O water -H···O H-bonding interactions to the supermolecular net.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq Zn1  (4)