1:1 Co-crystal of 4,4′-(ethene-1,2-diyl)dipyridin-1-ium sulfate and hexaaquairon(II) sulfate monohydrate

In the title hydrated double salt, 4,4′-(ethene-1,2-diyl)dipyridin-1-ium hexaaquairon(II) bis(sulfate) monohydrate, (C12H12N2)[Fe(H2O)6](SO4)2·H2O, the FeII cation is coordinated by six water molecules in a slightly distorted octahedral geometry; the two pyridine rings of the 4,4′-(ethene-1,2-diyl)dipyridin-1-ium cation are twisted to each other by a dihedral angle of 11.84 (10)°. In the crystal, the cations, sulfate anions and water molecules of crystallization are linked by O—H⋯O, N—H⋯O and weak C—H⋯O hydrogen bonds, forming a three-dimensional supramolecular network.


Related literature
For a related structure, see: Prakash et al. (2012). For the synthesis, see: Bok et al. (1975).
Supporting information for this paper is available from the IUCr electronic archives (Reference: XU5782). In this paper, we used [Mo(CN) 8 ] 3as building block to react with transition metal Fe 2+ ions and 1,2-di(pyridin-4-yl)ethylene ligand (dpe), in order to obtain octacyanometalate-based bimetallic compound. Unfortunately, the title ion-type compound was obtained. The asymmetric unit of the title compound contains one 1,2-bis-(4-pyridyl)ethylene cation, [H 2 dpe] 2+ , two sulfate anions, one hexaaqua-iron(II) cation, and one crystallized water molecule (Fig. 1). In the structure, the Fe atom adopts a distorted slightly octahedral geometry, in which the average distance of Fe-O bonds is about 2.118 Å. The [Fe(H 2 O) 6 ] 2+ cations, sulfate anions, and guest water molecules are linked by O-H···O hydrogen bonds, forming a two-dimensional (2-D) layered structure. The N-H···O hydrogen bonds between adjacent layers generate a 3-D supramolecular network (Fig. 2). The structure of the title compound is comparable to that observed in related compound (Prakash et al., 2012).

Refinement
All non-H atoms were refined anisotropically. The (C)H atoms of dpe were calculated at idealized positions and included in the refinement in a riding mode. The (N)H of dpe and (O)H atoms of water molecules were located from a difference  The molecular structure of the title compound with thermal ellipsoids at the 30% probability level. All H atoms were omitted for clarity.

Figure 2
The three-dimensional supramolecular network of the title compound.

4,4′-(Ethene-1,2-diyl)dipyridin-1-ium hexaaquairon(II) bis(sulfate) monohydrate
Crystal data (C 12 where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max = 0.001 Δρ max = 0.30 e Å −3 Δρ min = −0.42 e Å −3 Special details Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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.