N-[(1-Benzoylpiperidin-4-yl)methyl]benzamide

In the title compound, C20H22N2O2, the piperidine ring adopts a chair conformation. The phenyl rings are inclined to one another by 80.1 (1)° and make dihedral angles of 46.1 (1) and 40.2 (1)° with the mean plane of the piperidine ring. In the crystal, pairs of N—H⋯O hydrogen bonds link the molecules into inversion dimers. C—H⋯O interactions further link the molecules, forming a three-dimensional supramolecular network.

In the title compound, C 20 H 22 N 2 O 2 , the piperidine ring adopts a chair conformation. The phenyl rings are inclined to one another by 80.1 (1) and make dihedral angles of 46.1 (1) and 40.2 (1) with the mean plane of the piperidine ring. In the crystal, pairs of N-HÁ Á ÁO hydrogen bonds link the molecules into inversion dimers. C-HÁ Á ÁO interactions further link the molecules, forming a three-dimensional supramolecular network.

Comment
Biologically active alkaloids of substituted piperidines have been targeted for their total or partial synthesis (Ramalingan et al., 2004). Piperidines are known to have CNS depressant action at low dosage levels and stimulant activity with increased doses. In addition, the nucleus also possesses analgesic, anglionic blocking and anesthetic properties as well (Sergeant & May, 1970). We report in this communication, the synthesis and crystal structure of a new piperidine derivative.
The phenyl rings form dihedral angles of 46.1 (1)° and 40.2 (1)°, respectively, with the best plane through the piperidine The crystal packing shows N-H···O hydrogen bonds linking the molecules to centrosymmetric dimers (Fig. 2).

Experimental
The procedure (Prathebha et al., 2013, Venkatraj et al., 2008 adopted in the synthesis of the typical diamide is as follows: In a 250 mL round-bottomed flask 4-methyl piperidine (0.01 mol) was taken in, to which 100 mL of ethyl methyl ketone was added and stirred at room temperature. After 5 minutes, triethylamine (0.02 mol) was added and the mixture was stirred for 15 minutes. Then, benzoyl chloride (0.02 mol) was added and the reaction mixture was stirred at room temperature for about 2 h. A white precipitate of triethyl ammonium chloride was formed. It was filtered and the filterate was evaporated to get the crude product. The crude product was recrystallized twice from ethyl methyl ketone.
Melting Point: 127 °C, yield: 85%.  The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level.

Figure 2
The packing of the molecules in the crystal structure. The dashed lines indicate the hydrogen bonds.  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.