N,N′-Bis(phenylcarbamothioyl)benzene-1,3-dicarboxamide

The asymmetric unit of the title compound, C22H18N4O2S2, contains two molecules. In one of them, the dihedral angles between the central benzene ring and the phenyl rings are 16.97 (8) and 20.97 (8)°, while the phenyl rings make a dihedral angle of 37.87 (8)°. In the other molecule, the corresponding values are 34.92 (7), 53.90 (7) and 60.68 (8)°, respectively. In each molecule, two intramolecular N—H⋯O hydrogen bonds generate S(6) rings and a short C—H⋯S contact also occurs. In the crystal, N—H⋯S, N—H⋯O, C—H⋯O and C—H⋯S interactions link the molecules into a three-dimensional network.

The asymmetric unit of the title compound, C 22 H 18 N 4 O 2 S 2 , contains two molecules. In one of them, the dihedral angles between the central benzene ring and the phenyl rings are 16.97 (8) and 20.97 (8) , while the phenyl rings make a dihedral angle of 37.87 (8) . In the other molecule, the corresponding values are 34.92 (7), 53.90 (7) and 60.68 (8) , respectively. In each molecule, two intramolecular N-HÁ Á ÁO hydrogen bonds generate S(6) rings and a short C-HÁ Á ÁS contact also occurs. In the crystal, N-HÁ Á ÁS, N-HÁ Á ÁO, C-HÁ Á ÁO and C-HÁ Á ÁS interactions link the molecules into a three-dimensional network.
In each molecule, three set of S(6) hydrogen rings motif can be observe involving the N-H···O and C-H···S intramolecular interactions. An extensive intermolceular interactions of N-H···S, N-H···O, C-H···O and C-H···S link the molecules into a three-dimensional network (Fig. 2, Table 1).

Experimental
Isophthaloyl dichloride (1 mmol) in 15 ml of dry acetone was added drop wise to a suspension of potassium thiocyanate (2 mmol) in 15 ml of dry acetone. The mixture was stirred for 1 h at room temperature and the white potassium chloride (KCl) was filtered. Aniline (2 mmol) in dry acetone (15 ml) was added into the filtrate and heated under reflux for 7 h.
The mixture was cooled to room temperature and filtered. The filtrate was poured into ice in a beaker to form solid. The crude was filtered, washed with ethanol and recrystallized from ethanol-acetonitrile (1:1) solution to yield colourless blocks.

Refinement
N bound H atoms were located from difference Fourier maps and freely refined. The remaining H atoms were positioned geometrically and refined using a riding model with with C-H = 0.95 Å and U iso (H) = 1.2U eq (C).

Figure 2
The crystal packing of (I

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.