1-[(Cyclohexylidene)amino]-3-(prop-2-en-1-yl)thiourea

The asymmetric unit of the title compound, C10H17N3S, consists of three symmetry-independent molecules with distinctly different conformations, as indicated for example by the C—N—C—C torsion angles of −155.9 (3), 89.9 (3) and 81.1 (4)° along the bond between thiourea and allyl units. In the crystal, molecules are connected via N—H⋯N and N—H⋯S hydrogen bonds into chains extending along [110] that are further associated through C—H⋯N interactions into layers parallel to (001). The allyl group in one of the independent molecules is disordered over two sets of sites with an occupancy ratio of 0.853 (6):0.147 (6).

JTM thanks Tulane University for support of the Tulane Crystallography Laboratory.
Supporting information for this paper is available from the IUCr electronic archives (Reference: GK2613).

Comment
It is well known that thiosemicarbazides are the key intermediates used in the synthesis of many heterocyclic compounds such as thiazolidinones (Mague et al., 2014), triazols (Mohamed et al., 2014 and thiazoles (Akkurt et al., 2014a). Thiosemicarbazone derivatives have displayed various pharmacological properties such as analgesic (Bahat et al., 2006), antibacterial (Qandil et al., 2006), anti-fungal, anti-tumoral (Singh et al., 2001Kalyoncuoğlu et al., 1992) and antitubercular (Bahadur & Goel, 1976) activities. In view of these findings and as part of ongoing research in the domain of heterocyclic compounds of the 1,2,4-triazole class with expected biological activity we report the synthesis and crystal structure of the title compound.
The packing consists of layers parallel to (001) formed by molecules joined via N-H···N hydrogen bonds, N-H···S and C-H···N interactions ( Fig. 2 and Table 1).

Experimental
The title compound was prepared according to our previously reported method (Akkurt et al., 2014b). Colourless crystals suitable for X-ray diffraction were obtained by crystallization from ethanol (m.p. 438 K).

Refinement
H atoms attached to carbon were placed in calculated positions (C-H = 0.95 -0.99 Å) while those attached to nitrogen (except H8 on N8) were placed in locations derived from a difference map and their coordinates adjusted to give N-H = 0.91 Å. All H atoms were included as riding contributions with isotropic displacement parameters 1.2 times those of the attached atoms. There wasn't a clear indication of the H8 atom on N8 from the difference map, despite seeing all of the others on N but it couldn't be seen any significant difference in the bond distances between the molecule with N8 and the other two so it was put it in the calculated position. In the molecule 1 (with S1), atoms C1, C2 and C3 of the allyl group are disordered over two sites, with refined occupancies of 0.853 (6) and 0.147 (6).  Asymmetric unit of the title compound with intermolecular hydrogen bonds shown as dotted lines. Ellipsoids are drawn at the 50% probability level. Only the major contributor to the disordered allyl group in the molecule 1 (with S1) is shown.

1-[(Cyclohexylidene)amino]-3-(prop-2-en-1-yl)thiourea
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.