2-(7-Methyl-3-oxo-1-phenylperhydronaphthalen-4a-yl)malononitrile

In the title compound, C20H22N2O, both cyclohexane rings adopt chair conformations. Weak C—H⋯N and C—H⋯O hydrogen bonding is present in the crystal structure.

In the title compound, C 20 H 22 N 2 O, both cyclohexane rings adopt chair conformations. Weak C-HÁ Á ÁN and C-HÁ Á ÁO hydrogen bonding is present in the crystal structure.
As a part of our interest in the synthsis of some complex ring systems, we investigated the title compound, (I), which is a potential precursor in the preparation of multifunctional tricyclic compound. We report herein the crystal structure of the title compound.
The molecular structure of (I) is shown in Fig. 1. Bond lengths and angles in (I) are normal. Two six membered rings (cyclohexanone and cyclohexane) adopt an chair conformation. The crystal packing is stabilized by C-H···N and C-H···0 hydrogen bonding (Table 1).
Colorless single crystals of (I) suitable for X-ray analysis were obtained by slow evaporation the mixture solvents of ethyl acetate and petroleum ether.

Refinement
The carbon-bound hydrogen atoms were placed in calculated positions, with C-H = 0.95-1.00 Å, and refined using a riding model, with U iso (H) =1.5U eq (C) for methyl H atom and 1.2U eq (C) for the others. In the absence of significant anomalous scattering effects, Friedel pairs were averaged.
supplementary materials sup-2 Figures Fig. 1. The molecular structure of (I) with 30% probability displacement ellipsoids (arbitrary spheres for H atoms).

Special details
Geometry. All e.s. 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 Rfactors(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. Symmetry codes: (i) x, y−1, z; (ii) −x+1, y−1/2, −z; (iii) −x+1, y−1/2, −z+1.