1-(4-Chlorophenyl)-3-(3-chloro-pro-pionyl)thio-urea.

In the title compound, C10H10Cl2N2OS, the mol-ecule adopts a trans-cis conformation with respect to the position of the carbonyl group and the chloro-phenyl groups relative to the thiono group across the C-N bonds. The mol-ecule is stabilized by an N-H⋯O hydrogen bond. In the crystal, mol-ecules are linked by N-H⋯S and C-H⋯O hydrogen bonds, forming zigzag chains along the b-axis direction. C-H⋯π inter-actions are also present.

In the title compound, C 10 H 10 Cl 2 N 2 OS, the molecule adopts a trans-cis conformation with respect to the position of the carbonyl group and the chlorophenyl groups relative to the thiono group across the C-N bonds. The molecule is stabilized by an N-HÁ Á ÁO hydrogen bond. In the crystal, molecules are linked by N-HÁ Á ÁS and C-HÁ Á ÁO hydrogen bonds, forming zigzag chains along the b-axis direction. C-HÁ Á Á interactions are also present.
The whole molecule is not planar (Fig. 1) because of the dihedral angle of 14.36 (12)° between chlorophenylamine, Cl2/(C5-C10)/N2, and thiourea C5/N2/C4/N1/S1 fragments. Both fragments are each planar with maximum deviation of 0.015 (3)Å for N2 atom from the least square plane of the thiourea fragment. The bond lengths and angles are in normal ranges (Allen et al. 1987). The molecule maintains trans-cis configuration with respect to the position of chloropropionyl and chlorophenyl against the thiono group about N1-C4 and N2-C4 bonds, respectively.

Experimental
4-chloroaniline (1.27 g, 0.01 mol) disolved in 30 ml of acetone was added into a solution of 3-chloropropionyl isothiocyanate (1.49 g, 0.01 mol) in 30 ml acetone. The mixture was refluxed for 2 hours. The solution was filtered and left to evaporate at room temperature. The white precipitate obtained after a few days, was washed with water and cold ethanol.
The colorless crystals were obtained by recrystallization from ethanol.

Refinement
After location in the difference map, the H-atoms attached to the C and N atoms were fixed geometrically at ideal positions and allowed to ride on the parent atoms with C-H = 0.93-0.97 Å, N-H = 0.86 Å and with U iso (H)=1.2U eq (C or N).

Computing details
Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008), PARST (Nardelli, 1995) and PLATON (Spek, 2009   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 > 2sigma(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.