1-(2,4-Difluorophenyl)thiourea

The asymmetric unit of the title compound, C7H6F2N2S, consists of two independent molecules, with comparable geometries. In one molecule, the thiourea moiety is essentially planar (r.m.s. deviation = 0.014 Å) and it forms a dihedral angle of 78.67 (9)° with the benzene ring. The corresponding r.m.s. deviation and dihedral angle for the other molecule are 0.011 Å and 81.71 (8)°, respectively. In both molecules, one of the F atoms is disordered over two positions with refined site occupancies of 0.572 (3):0.428 (3) and 0.909 (2):0.091 (2), respectively. In the crystal, molecules are linked via N—H⋯S and C—H⋯F hydrogen bonds into two-dimensional networks parallel to (010).

The asymmetric unit of the title compound, C 7 H 6 F 2 N 2 S, consists of two independent molecules, with comparable geometries. In one molecule, the thiourea moiety is essentially planar (r.m.s. deviation = 0.014 Å ) and it forms a dihedral angle of 78.67 (9) with the benzene ring. The corresponding r.m.s. deviation and dihedral angle for the other molecule are 0.011 Å and 81.71 (8) , respectively. In both molecules, one of the F atoms is disordered over two positions with refined site occupancies of 0.572 (3):0.428 (3) and 0.909 (2):0.091 (2), respectively. In the crystal, molecules are linked via N-HÁ Á ÁS and C-HÁ Á ÁF hydrogen bonds into two-dimensional networks parallel to (010).

Related literature
For general background to and the related structures of the title compound, see: Fun et al. (2012a,b); Sarojini et al. (2007). For standard bond-length data, see: Allen et al. (1987). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986).

Comment
In continuation of our work on the synthesis of thiourea derivatives (Fun et al., 2012a(Fun et al., , 2012bSarojini et al., 2007), the title compound is prepared and its crystal structure is reported here.
The asymmetric unit ( Fig. 1) of the title compound consists of two independent molecules (A and B), with comparable geometries. In molecule A, thiourea moiety (S1A/N1A/N2A/C7A) is essentially planar (r.m.s. deviation = 0.014 Å) and it forms a dihedral angle of 78.67 (9)° with the benzene ring (C1A-C6A). The corresponding r.m.s. deviation and dihedral angle for molecule B are 0.011 Å and 81.71 (8)°, respectively. Bond lengths (Allen et al., 1987) and angles are within normal ranges and are comparable to related structures (Fun et al., 2012a(Fun et al., , 2012b In the crystal structure, Fig. 2, molecules are linked via intermolecular N-H···S and C-H···F hydrogen bonds (Table   1) into two-dimensional networks parallel to (010).
Experimental 2,4-Difluoroaniline (0.84 mL, 0.0081 mol) was refluxed with potassium thiocyanate (1.4 g, 0.0142 mol) in 20 mL of water and 1.6 mL of concentrated HCl for 3 h. The reaction mixture was then cooled to room temperature and stirred overnight. The precipitated product was then filetred, washed with water, dried and recrystallised from acetone and toluene (1:1) mixture by slow evaporation method (m.p. 441-443K).

1-(2,4-Difluorophenyl)thiourea
Crystal data C 7 H 6 F 2 N 2 S M r = 188.20 Monoclinic, P2 1 /c Hall symbol: -P 2ybc a = 6.4260 (7) Å b = 36.908 (4) Å c = 6.6821 (7) (Cosier & Glazer, 1986) operating at 100.0 (1) K. 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.