2-[Anilino(phenyl)methyl]cycloheptanone

In the title compound, C20H23NO, the cycloheptanone ring adopts a twist-chair conformation, with the aminomethyl substituent in an equatorial position. The relative configuration of the two stereocenters is R,R. In the crystal, molecules are linked by N—H⋯O hydrogen bonds into chains along [100].

In the title compound, C 20 H 23 NO, the cycloheptanone ring adopts a twist-chair conformation, with the aminomethyl substituent in an equatorial position. The relative configuration of the two stereocenters is R,R. In the crystal, molecules are linked by N-HÁ Á ÁO hydrogen bonds into chains along [100].   Table 1 Hydrogen-bond geometry (Å , ). Mannich reaction (Eftekhari-Sis et al., 2006;Azizi et al., 2006;Cordova, 2004) is one of the most important basic reactions in organic chemistry for its use in natural product and pharmaceutical syntheses due to formation of C-C and C-N bonds, simultaneously, to furnish β-amino ketones, which exhibit biological activity such as anti-inflammatory (Jadhav et al., 2008)

Experimental
The title compound was obtained by adding of 0.04 g of Laponite-HPMC nano composite (Eftekhari-Sis et al., 2013) to a mixture of 0.5 mmol of benzaldehyde, 0.5 mmol of aniline and 3 equiv. of cycloheptanone and stirring at room temperature for 24 h. After completion of the reaction, 5 ml EtOH was added and the catalyst was removed by filtration.
The filtrate was concentrated under reduced pressure. The obtained crude product was recrystallized from EtOH to afford the title compound in 60% yield. Colorless crystals suitable for crystal structure determination were grown from 96% EtOH.

Refinement
Carbon bound H atoms were positioned geometrically, with C-H=0.93, 0.97, and 0.98 Å for aromatic, methylene and methine H, and constrained to ride on their parent atoms, with U iso (H) = 1.2Ueq(C). The nitrogen H atoms were located from the difference Fourier map and allowed to refine freely.  The structure of title compound, showing 40% probability displacement ellipsoids and the atom numbering scheme.

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.