N-(2,6-Dimethylphenyl)-N′-propanoylthiourea

In the title compound, C12H16N2OS, an intramolecular N—H⋯O hydrogen bond forms an S(6) ring motif. The propionylthiourea group is approximately planar [with a maximum deviation of 0.135 (2) Å] and forms a dihedral angle of 83.39 (7)° with the benzene ring. In the crystal, molecules are linked by pairs of N—H⋯S hydrogen bonds, forming centrosymmetric dimers and generating R 2 2(8) ring motifs.

In the title compound, C 12 H 16 N 2 OS, an intramolecular N-HÁ Á ÁO hydrogen bond forms an S(6) ring motif. The propionylthiourea group is approximately planar [with a maximum deviation of 0.135 (2) Å ] and forms a dihedral angle of 83.39 (7) with the benzene ring. In the crystal, molecules are linked by pairs of N-HÁ Á ÁS hydrogen bonds, forming centrosymmetric dimers and generating R 2 2 (8) ring motifs.

Mohd Sukeri Mohd Yusof, Siti Fatimah Abdul Mutalib, Suhana Arshad and Ibrahim Abdul Razak Comment
The title compound is analogous to N-propionylthiourea, (Yamin & Othman, 2008) except that the hydogen atom at the N terminal atom is replaced by a 2,6-dimethylphenyl group.

Experimental
To a stirring acetone solution (75 ml) of propionyl chloride (2.42 g, 0.03 mol) and ammonium thiocyanate (2.0 g, 0.03 mol), 2,6-dimethylaniline (3.64 g, 0.03 mol) in 40 ml of acetone was added dropwise. The mixture was refluxed reflux for 1 h. The resulting solution was poured into a beaker containing ice blocks. The white precipitate was filtered off and washed with distilled water and cold ethanol before being dried under vacuum. Good quality crystals were obtained by recrystallization from DMSO.

Refinement
N-bound H atoms were located from the difference map and refined freely, [N-H = 0.85 (2) and 0.87 (2) Å]. The remaining H atoms were positioned geometrically [C-H = 0.95-0.99 Å] and refined using a riding model with U iso (H) = 1.2 or 1.5 U eq (C). A rotating group model was applied to the methyl groups.

Figure 2
The crystal packing of the title compound. The H atoms not involved in the intermolecular interactions (dashed lines) have been omitted for clarity.  (Cosier & Glazer, 1986) operating at 100.0 (1) K. 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.