2-(4-Methylcyclohex-3-enyl)propan-2-yl N-phenylcarbamate

In the title carbamate compound, C17H23NO2, one of the Csp 3 atoms of the cyclohexene ring is disordered over two sites with refined occupancies of 0.55 (2) and 0.45 (2), both disorder components resulting in half-boat conformations. The mean plane through the carbamate unit is inclined at interplanar angles of 14.80 (13), 18.30 (17) and 24.0 (2)°, respectively, with respect to the phenyl ring, and the major and minor disorder component cyclohexene rings. In the crystal structure, adjacent molecules are linked into chains along [001] via intermolecular N—H⋯O hydrogen bonds. The crystal structure is further stabilized by weak intermolecular C—H⋯π interactions.

In the title carbamate compound, C 17 H 23 NO 2 , one of the Csp 3 atoms of the cyclohexene ring is disordered over two sites with refined occupancies of 0.55 (2) and 0.45 (2), both disorder components resulting in half-boat conformations. The mean plane through the carbamate unit is inclined at interplanar angles of 14.80 (13), 18.30 (17) and 24.0 (2) , respectively, with respect to the phenyl ring, and the major and minor disorder component cyclohexene rings. In the crystal structure, adjacent molecules are linked into chains along [001] via intermolecular N-HÁ Á ÁO hydrogen bonds. The crystal structure is further stabilized by weak intermolecular C-HÁ Á Á interactions.
Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009). including steroids as well as primary and secondary alcohols, polyols, phenols with sodium cynate, and trifluoroacetic acid (Loev & Kormendy, 1963), by carbonylation of aromatic nitro compounds (Lapidus et al., 1987), by the reaction of isocynates with alcohols (Ibuka et al., 1985) in the presence of lewis acid and by the reaction of an amine and an alcohol with phosgene. Phytosterol, β-Sitosterol, stigmasterol and cholesterol react with phenyl isocyanate to give carbamate (Banerjee et al., 1978;Graia et al., 2009). In this study the title compound has been synthesized by the reaction of α-terpineol with phenylisocyanate in the presence of catalytic amount of HCl in chloroform solvent.

Experimental
A mixture of α-terpineol (1.640 ml) and phenylisocyanate (1.087 ml) in 1:1 molar ratio were stirred in chloroform for 30 minutes in the presence of catalytic amount of HCl. The reaction mixture was dried on rota vapor at low pressure and then chromatographed over silica gel column loaded in light petroleum ether. The column was eluted only with light petroleum ether to give five fractions of the title compound. These fractions were mixed together on the basis of same TLC results and crystallized with chloroform:alcohol (1:1) to give the colourless needles of (I) (1.93 g, M.p. 378 K). The melting point was taken on Thermo Fisher digital melting point apparatus of IA9000 series and is uncorrected. Open column chromatography was performed on silica gel 60 (Merck, 0.040-0.063 mm, 230-400 mesh ASTM) and Sephadex LH-20 (Pharmacia). TLCs were taken on silica gel plates (silica gel 60 F 254 on aluminum foil, Merck).
supplementary materials sup-2 Refinement Atom C10 is disordered over two sites with a refined occupancy ratio of 0.55 (2):0.45 (2). Atom C10B of the minor disordered component was refined isotropically. The C-C bond lengths in the minor disordered component were restrained with distance of 1.50 (1) Å. All H atoms were placed in their calculated positions, with N-H = 0.86 and C-H = 0.93 or 0.96 Å, and refined using a riding model, with U iso = 1.2 U eq (N) and U iso = 1.2 or 1.5 U eq (C). The rotating group model was applied to the methyl groups. In the absence of significant anomalous dispersion, 1491 Friedel pairs were merged in the final refinement.

Special details
Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq Occ. (