1-(2-Chlorobenzoyl)-3-(2-trifluoromethylphenyl)thiourea

The dihedral angle between the benzene rings in the title compound, C15H10ClF3N2OS, is 54.02 (4)°. An intramolecular N—H⋯O hydrogen bond occurs. In the crystal, N—H⋯S hydrogen bonds link the molecules into inversion dimers.

The dihedral angle between the benzene rings in the title compound, C 15 H 10 ClF 3 N 2 OS, is 54.02 (4) . An intramolecular N-HÁ Á ÁO hydrogen bond occurs. In the crystal, N-HÁ Á ÁS hydrogen bonds link the molecules into inversion dimers.

M. Khawar Rauf, Masahiro Ebihara and Amin Badshah Comment
The background to this study has been set out in our previous work for the structural and coordination chemistry of N,N′disubstituted thioureas (Rauf et al., 2012). Herein, as a continuation of these crytallographic studies, the structure of the title compound (I) is described, Fig. 1 2)]. This is associated with the expected typical thiourea intramolecular N-H···O hydrogen bond, forming a six-membered ring commonly observed in this class of compounds (Rauf et al., 2012). In the crystal packing of (I), intermolecular N-H···S H-bonds link the molecules into centrosymmetric dimers (Fig.2).

Experimental
Freshly prepared 2-chlorobenzoylisothiocyanate (1.98 g, 10 mmol) was dissolved in tetrahydrofuran (35 ml) and stirred for 40 minutes. Afterwards neat 2-trifluoromethylaniline (1.61 g, 10 mmol) was added and the resulting mixture was stirred for 1 h. The reaction mixture was then poured into acidified water and stirred well. The solid product was separated and washed with deionized water and purified by recrystallization from chloroform to give crystals of the title compound (I), with an overall yield of 94% (3.4 g). M.P. 156-157°C Anal. calcd. for C 15 H 10 ClF 3 N 2 OS; C,50.22 H,2.81 N,7.81 S,8.94% Found: C,50.20 H,2.80 N,7.81 S,8.93%.

Refinement
The F atoms of the trifluoromethyl group are disordered over two sites with a site occupation factor of 0.52 (9):0.48 (9) for the major and minor occupied sites respectively and were refined isotropically. Hydrogen atoms were included in calculated positions and refined as riding on their parent atom with N-H = 0.88 Å and U iso (H) = 1.2U(N eq ), C aromatic -H = 0.95 Å and U iso (H) = 1.2U(C eq ).  ORTEP of (I). Displacement ellipsoids are drawn at the 50% probability level. Hydrogen bonds shown as dashed lines.

Figure 2
Packing diagram of (I). Hydrogen bonds 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.