Crystal structure of 1-(2-aminophenyl)-3-phenylurea

In the title compound, C13H13N3O, the phenyl ring makes a dihedral angle of 47.0 (1)° with the mean plane of the –NC(=O)N– unit, while the dihedral angle between the latter mean plane and the aminophenyl ring is 84.43 (7)°. In the crystal, molecules are linked via N—H⋯O hydrogen bonds involving the central –NHC(=O)NH– units, forming chains running parallel to the b axis. These chains associate with one another via N—H⋯O and N—H⋯N hydrogen bonds, from the pendant amino groups to the –NHC(=O)NH– units of adjacent molecules, forming columns propagating along [010]. The structure was refined as a two-component twin with a 0.933 (3):0.067 (3) domain ratio.


S1. Comment
Compounds bearing a urea linkage have attracted the interest of many researchers due to the variety of their applications in both of medicinal and industrial fields. One of the most important class of compounds that are used in the cosmetic industry are urea-containing compounds due to their effective moisturizing properties (Kapuscinska & Nowak, 2014).
Urea-linked glycosides serve as small-molecule H-bond donors in asymmetric catalysis (Doyle & Jacobsen, 2007), and are currently employed in the forestry product industry, for example as adhesive mixtures to reduce the level of toxic phenol in furniture and building materials (Helm et al., 1989). Some urea derivatives possess valuable antituberculosis, antibacterial and anticonvulsant properties (Upadhayaya et al., 2009;Khan et al., 2008, Sett et al., 2004Koçyiğit-Kaymakçıoğlu et al., 2005). Compounds such as Thidiazuron have mimicked the effect of benzyladenine (BA) in the Ca 2+ and cytokinin systems (Yip et al., 1986). Based on such findings we report in this study the synthesis and crystal structure of the title compound.
The phenyl ring makes a dihedral angle of 47.0 (1)° with the mean plane of atoms N1/N2/C7/O1 while the dihedral angle between the latter unit and the aminophenyl ring is 84.43 (7)°.

S2. Experimental
A mixture of 0.01 mol (2.06 g m) of N-phenylmorpholine-4-carboxamide and 0.01 mol (1.08 g m) benzene-1,2-diamine in 20 ml of ethanol was heated under reflux for 10 h. On cooling, the resulting solid product was collected by filtration, washed with a little cold ethanol and dried under vacuum. Colourless crystals suitable for X-ray diffraction were obtained by recrystallization of the product from ethanol (m.p.: 495 K; yield: 73%).

S3. Refinement
The The molecular structure of the title compound, with atom labelling. Displacement ellipsoids are drawn at the 50% probability level.

Figure 2
A view along the c axis of the crystal packing of the title compound. The N-H···O and N-H···N hydrogen bonds are shown by blue and violet dashed lines, respectively (see Table 1 for details).

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. H-atoms attached to carbon were placed in calculated positions (C-H = 0.95 Å) while those attached to nitrogen were placed in locations derived from a difference map and their parameters adjusted to give N-H = 0.91 Å. All were included as riding contributions with isotropic displacement parameters 1.2 times those of the attached atoms. In the final stages of the refinement, analysis of the data with the TWINROTMAT routine in PLATON (Spek, 2014) indicated the presence of a minor twin component rotated by approximately 180° about b and the data were finally refined as a 2-component twin.