Bis[4-amino-N-(pyrimidin-2-yl-κN)benzenesulfonamidato-κN](4,4′-dimethyl-2,2′-bipyridine-κ2 N,N′)cadmium dimethylformamide disolvate

In the title compound, [Cd(C10H9N4O2S)2(C12H12N2)]·2C3H7NO, the CdII ion lies on a twofold rotation axis, is six-coordinated by N atoms, and displays a trigonal–prismatic geometry arising from the two sulfadiazinate ligands and one 4,4′-dimethyl-2,2′-bipyridine ligand. Both ligands are bidentate and coordinate via their N atoms. The O and carbonyl C atoms of the dimethylformamide molecule show disorder and were modelled with two different orientations and with site occupancies of 0.584 (10):0.416 (10). The geometry around the sulfadiazine S atom is distorted tetrahedral. The crystal structure involves N—H⋯O hydrogen bonds which link molecules into a three-dimensional network. Weak C—H⋯O hydrogen bonds are also observed.

In the title compound, [Cd(C 10 H 9 N 4 O 2 S) 2 (C 12 H 12 N 2 )]Á-2C 3 H 7 NO, the Cd II ion lies on a twofold rotation axis, is sixcoordinated by N atoms, and displays a trigonal-prismatic geometry arising from the two sulfadiazinate ligands and one 4,4 0 -dimethyl-2,2 0 -bipyridine ligand. Both ligands are bidentate and coordinate via their N atoms. The O and carbonyl C atoms of the dimethylformamide molecule show disorder and were modelled with two different orientations and with site occupancies of 0.584 (10):0.416 (10). The geometry around the sulfadiazine S atom is distorted tetrahedral. The crystal structure involves N-HÁ Á ÁO hydrogen bonds which link molecules into a three-dimensional network. Weak C-HÁ Á ÁO hydrogen bonds are also observed.

Related literature
For the comparison of the N-H bond distance of the terminal amine group and the C-S-N-C torsion angle, see: Heren et al. (2006); Hossain & Amoroso (2007); Hossain (2011). For the hydrogen bonds of sulfadiazinate anions, see: Paşaog lu et al. (2008). For the comparison of the dihedral angle between the aromatic rings of the anion, see: Hossain & Amoroso (2007); Hossain (2011). For the comparison of Cd-N bond distances, see: Kalateh et al. (2010); Hossain (2011).
The bond distance C18-N14 of 1.359 (3)Å is comparable with the value of 1.366 (5)Å (Hossain, 2011). The torsion angle C15-S11-N11-C11 of 53.5 (2)° is less than the value of 66.1 (3)° and the dihedral angle between the aromatic rings of the anion of 76.60 (8)° is also smaller than the value of 88.65 (12)° in the sulfadiazinate anion (Hossain, 2011) because the large 4,4′-dimethyl-2,2′-bipyridine (dmbpy) ligand is attached to the Cd ion in the complex. Due to the presence of the larger dmbpy molecule the torsion and dihedral angles are reduced from the latter one where small dmf molecules are attached with the metal centre. In the title complex, (I), the O and formido C atoms of the solvated dimethylformamide show disorder and were modeled as two different orientations with site occupancies of 0.584 (10):0.416 (10).

Experimental
The sodium salt of sulfadiazine (Nasdz, 0.5446 g, 2 mmol) was dissolved in hot methanol (50 ml) and a methanol solution (10 ml) of (CH 3 COO) 2 Cd.2H 2 O (0.26647 g, 1 mmol) was added slowly with constant stirring on a hot plate. A white precipitate was formed and the mixture was stirred for a further 2 h. The precipitate was filtered off and dried over silica gel; it was then dissolved in dimethylsulfoxide solution (50 ml), and 4,4′-dimethyl-2,2′-bipyridine (0.1841 g, 1 mmol) was added, stirred for 10 min., filtered and left for crystallization. A week later, white block-shaped crystals of (1) were filtered off and dried over silica gel.

Refinement
The O and formido C atoms of dimethylformamide show disorder and were modeled with two different orientations and

Figure 1
The molecular structure of the title compound (I), with atom labels and 50% probability displacement ellipsoids for non-  The packing of (I), viewed down the b-axis, showing one layer of molecules connected by N-H···O hydrogen bonds (dashed lines). Secondary atom site location: difference Fourier map Hydrogen site location: inferred from neighbouring sites H atoms treated by a mixture of independent and constrained refinement w = 1/[σ 2 (F o 2 ) + (0.0369P) 2 + 6.0396P] where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.55 e Å −3 Δρ min = −0.59 e Å −3 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.