(2,2′-Bipyridine-κ2 N,N′)dibromido(dimethyl sulfoxide-κO)zinc(II)

In the molecule of the title compound, [ZnBr2(C10H8N2)(C2H6OS)], the ZnII atom is five-coordinated in a distorted trigonal–bipyramidal configuration by two N atoms from one 2,2′-bipyridine, one O atom from one dimethylsulfoxide molecule and two Br atoms. Intermolecular π–π stacking between parallel pyridine rings [face-to-face distance 3.32 (4) Å] and C—H⋯Br and C—H⋯O hydrogen-bonding interactions are present in the crystal structure.

In the molecule of the title compound, [ZnBr 2 (C 10 H 8 N 2 )-(C 2 H 6 OS)], the Zn II atom is five-coordinated in a distorted trigonal-bipyramidal configuration by two N atoms from one 2,2 0 -bipyridine, one O atom from one dimethylsulfoxide molecule and two Br atoms. Intermolecularstacking between parallel pyridine rings [face-to-face distance 3.32 (4) Å ] and C-HÁ Á ÁBr and C-HÁ Á ÁO hydrogen-bonding interactions are present in the crystal structure.
In the molecule of the title compound, (I), (Fig. 1), the Zn II atom is five-coordinate in a distorted trigonal-bipyramidal configurations by two N atoms from one 2,2'-bipyridine, one atom from one dimethyl sulfoxide and two Br atoms. The Zn-N and Zn-O bond lengths and angles (Table 1)

Experimental
For the preparation of the title compound, (I), a solution of 2,2'-bipyridine (0.17 g, 1.10 mmol) in methanol (10 ml) was added to a solution of ZnBr 2 (0.25 g, 1.10 mmol) in methanol (5 ml) at room temperature. The suitable crystals for X-ray diffraction experiment were obtained by methanol diffusion to a colorless solution in DMSO. Suitable crystals were isolated after one week (yield; 0.36 g, 71.2%).

Refinement
H atoms were positioned geometrically with C-H = 0.93 Å for aromatic and 0.96 Å for methyl, and constrained to ride on their parent atoms with U iso (H)=1.2U eq (C).

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 Rfactors(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.