N-(Cyanomethyl)benzamide

In the structure of the title compound, C9H8N2O, the amide group is twisted by a dihedral angle of 21.86 (7)° with respect to the benzene ring, while the planes of the benzene ring and cyanomethyl group form a dihedral angle of 53.13 (11)°. In the crystal structure, molecules are linked via N—H⋯O hydrogen bonds, forming a chain running parallel to the a axis.

In the structure of the title compound, C 9 H 8 N 2 O, the amide group is twisted by a dihedral angle of 21.86 (7) with respect to the benzene ring, while the planes of the benzene ring and cyanomethyl group form a dihedral angle of 53.13 (11) . In the crystal structure, molecules are linked via N-HÁ Á ÁO hydrogen bonds, forming a chain running parallel to the a axis.

Comment
Tetrazoles derivatives are an important class of compounds, which can be used in the fields of bioorganic and medicinal chemistry as antibacterials, anti-cancer, heart disease, neurodegenerative disease, and antifungal activity (Smissman et al.,1976;McGuire et al., 1990;Lunn et al., 1992;Itoh et al., 1995;Upadhayaya et al., 2004;Wu et al., 2008;Rostom et al., 2009. The tetrazole moiety has long been established as a bioisostere of a carboxyl unit (Burger, 1991). A major advantage of tetrazoles over carboxylic acids is that they are resistant to many biological metabolic degradation pathways (Singh et al., 1980).
With the aim of developing new tetrazolic derived, an analog isosteric of the glycine, we have prepared N-(cyanomethyl)benzamide, a key intermediate, starting from aminoacetonitrile hydrogen sulphate.
In the title compound, the amide group is rotated by 21,86° out of the plane of the benzene ring (Fig. 1). The crystal packing is stabilized by N-H···O hydrogen bonds (Table 1) to form infinite chains parallel to the a axis (Fig. 2).

Experimental
Aminoacetonitrile hydrogen sulphate was prepared in two steps from technical formaldehyde (Adams & Langley, 1941a,b).
To a solution of 10 mmol s of aminoacetonitrile hydrogen sulfate in 10 ml of methylene chloride, triethylamine was added until neutral pH at cold temperature (0 <T< 5°C ), then 11 mmol s of Benzoyl chloride was added at the same temperature.
The mixture was stirred at 0°C for 1 hour. The whole is taken to room temperature and left under magnetic agitation during 16 hours. After reaction, the mixture was washed 3 times with a solution of citric acid 15%; then, the organic solution is dried over sodium sulphate and evaporated under reduced pressure. The residue was crystallized from a mixture ether/hexane (1:1) to give white solid in 82% yield. m.p.: 138-140°C .
The structure of the product was established on the basis of NMR spectroscopy ( 1 H, 13 C ), MS data and elemental analysis.
Single crystals of the title compound were obtained from an ethanolic solution and used for X-ray diffraction studies at room temperature.

Refinement
All H atoms were located in a difference map and refined without any distance restraints.

Special details
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 > 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.