1-(3-Chlorobenzoyl)-3-(2,3-dimethylphenyl)thiourea

The title molecule, C16H15ClN2OS, exists in the solid state in its thione form with typical thiourea C—S and C—O bonds lengths, as well as shortened C—N bonds. An intramolecular N—H⋯O hydrogen bond stabilizes the molecular conformation and intermolecular N—H⋯S hydrogen bonds link the molecules into centrosymmetric dimers. The dihedral angle between the aromatic rings is 50.18 (5)°.

The title molecule, C 16 H 15 ClN 2 OS, exists in the solid state in its thione form with typical thiourea C-S and C-O bonds lengths, as well as shortened C-N bonds. An intramolecular N-HÁ Á ÁO hydrogen bond stabilizes the molecular conformation and intermolecular N-HÁ Á ÁS hydrogen bonds link the molecules into centrosymmetric dimers. The dihedral angle between the aromatic rings is 50.18 (5) .

Related literature
For related compounds, see: Khawar Rauf et al. (2006a,b,c,d Table 1 Hydrogen-bond geometry (Å , ). supporting information Acta Cryst. (2009). E65, o240 [doi:10.1107/S1600536809000063] 1-(3-Chlorobenzoyl)-3-(2,3-dimethylphenyl)thiourea M. Khawar Rauf, Michael Bolte and Amin Badshah S1. Comment The background to this study has been set out in our previous work on the structural chemistry of N, N′-disubstituted thioureas (Khawar Rauf et al., 2006a,b,c,d). Herein, as a continuation of these studies, the structure of the title compound (I) is described. A depiction of the molecule is given in Fig. 1. Bond lengths and angles, see the table of selected geometric parameters, can be regarded as typical for N,N′-disubstituted thiourea compounds as found in the Cambridge Structural Database v5.28 (Allen, 2002;Khawar Rauf et al., 2006a).The molecule exists in the thione form with typical thiourea C -S and C-O bonds, as well as shortened C-N bond lengths. The thiocarbonyl and carbonyl groups are almost coplanar. The dihedral angle between the aromatic rings is 50.18 (5)°. An intramolecular N-H···O hydrogen bond is present (Table 2), forming a six-membered ring commonly observed in this class of compounds (Khawar Rauf et al., 2006d). Intermolecular N-H···S hydrogen bonds link the molecules to form centrosymmetric dimers.

S2. Experimental
Freshly prepared 3-chlorobenzoyl isothiocyanate (2.0 g, 10 mmol) was stirred in acetone (40 ml) for 20 min. Neat 2,3-dimethylaniline (1.62 g, 10 mmol) was then added and the resulting mixture was stirred for 1.5 h. The reaction mixture was then poured into acidified (pH 4) water and stirred well. The solid product was separated and washed with deionized water and purified by recrystallization from methanol-1,1-dichloromethane (1:10 v/v) to give fine crystals of (I), with an overall yield of 90%. Full spectroscopic and physical characterization will be reported elsewhere.

S3. Refinement
H atoms bonded to C were included in calculated positions and refined as riding on their parent C atom with C-H = 0.95 Å U iso (H) = 1.2U eq (C) or C-H = 0.98 Å and U iso (H) = 1.5U eq (C), respectively, for aromatic and methyl C atoms.
The H atoms bonded to N were freely refined.   Packing diagram. 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.