Trichlorido(5,5′-dimethyl-2,2′-bipyridine-κ2 N,N′)(dimethylformamide-κO)indium(III) hemihydrate

The asymmetric unit of the title compound, [InCl3(C12H12N2)(C3H7NO)]·0.5H2O, contains two independent InIII complex molecules with similar structures and one lattice water molecule. In each complex molecule, the InIII atom is six-coordinated in a distorted octahedral geometry, formed by two N atoms from the chelating 5,5′-dimethyl-2,2′-bipyridine ligand, one O atom from a dimethylformamide and three facial Cl atoms. In the crystal, the lattice water molecule is linked to the complex molecules via O—H⋯Cl hydrogen bonds. Further weak C—H⋯Cl and C—H⋯O hydrogen bonds result in the formation of a three-dimensional structure.

The asymmetric unit of the title compound, [InCl 3 (C 12 H 12 N 2 )-(C 3 H 7 NO)]Á0.5H 2 O, contains two independent In III complex molecules with similar structures and one lattice water molecule. In each complex molecule, the In III atom is sixcoordinated in a distorted octahedral geometry, formed by two N atoms from the chelating 5,5 0 -dimethyl-2,2 0 -bipyridine ligand, one O atom from a dimethylformamide and three facial Cl atoms. In the crystal, the lattice water molecule is linked to the complex molecules via O-HÁ Á ÁCl hydrogen bonds. Further weak C-HÁ Á ÁCl and C-HÁ Á ÁO hydrogen bonds result in the formation of a three-dimensional structure.
We are grateful to the Islamic Azad University, Omidieh Branch, for financial support.
The asymmetric unit of the title compound, (Fig. 1), contains two crystallographically independent [In(C 12 H 12 N 2 )Cl 3 (C 3 H 7 NO)] molecules and one water solvent molecule. The In III atom is six-coordinated in a distorted octahedral configuration by two N atoms from the chelating 5,5′-dimethyl-2,2′-bipyridine ligand, one O atom from a dimethylformamide and three Cl atoms. The In-Cl, In-O and In-N bond lengths and angles are collected in Table 1. In the crystal structure, intermolecular O-H···Cl and C-H···O and C-H···Cl hydrogen bonds link the molecules (Fig. Table 2).

Experimental
For the preparation of the title compound, a solution of 5,5′-dimethyl-2,2′-bipyridine (0.30 g, 1.65 mmol) in methanol (10 ml) was added to a solution of InCl 3 .4H 2 O (0.48 g, 1.65 mmol) in methanol (10 ml) and the resulting colorless solution was stirred for 20 min at 323 K. The suitable crystals for X-ray diffraction experiment were obtained by methanol diffusion to a colorless solution in dimethylformamide. Suitable crystals were isolated after one week (yield; 0.58 g, 72.1%).

Refinement
Water H atoms were located in a difference Fourier map and refined with O-H distance of 0.84 (2) Å, U iso (H) = 0.1 Å 2 .
Other H atoms were positioned geometrically with C-H = 0.93 Å for aromatics H and 0.96 Å for methyl H atoms constrained to ride on their parent atoms, U iso (H) = 1.2U eq (C).  The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.

Figure 2
Unit-cell packing diagram for title molecule. Hydrogen bonds are shown as dashed lines.

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 C1 0.5123 (