2,2,2-Tribromo-N-(2-methylphenyl)acetamide

The asymmetric unit of the title compound, C9H8Br3NO, contains two independent molecules. Intramolecular N—H⋯Br hydrogen bonds are present in both molecules. In the crystal, molecules are packed into columnar chains by intermolecular N—H⋯O hydrogen bonds.

The asymmetric unit of the title compound, C 9 H 8 Br 3 NO, contains two independent molecules. Intramolecular N-HÁ Á ÁBr hydrogen bonds are present in both molecules. In the crystal, molecules are packed into columnar chains by intermolecular N-HÁ Á ÁO hydrogen bonds.

Comment
As part of a study of the effect of ring and the side chain substituents on the solid state structures of N-aromatic amides (Gowda et al., 2009(Gowda et al., , 2010, the structure of 2,2,2-tribromo-N-(2-methylphenyl)acetamide has been determined (Fig.1). The asymmetric unit of the structure contains two independent molecules. The conformation of the N-H bond in the structure is anti to the C=O bond in the side chain, similar to that observed in 2,2,2-tribromo-N-(phenyl)acetamide, 2,2,2-tribromo-

Experimental
The title compound was prepared from o-toluidine, tribromoacetic acid and phosphorylchloride according to the literature method (Gowda et al., 2003). The purity of the compound was checked by determining its melting point. It was further characterized by recording its infrared spectra. Single crystals of the title compound used for X-ray diffraction studies were obtained by a slow evaporation of its solution in petroleum ether at room temperature.

Refinement
The H atoms of the NH groups were located in a difference map and later restrained to the distance N-H = 0.86 (4) Å. The other H atoms were positioned with idealized geometry using a riding model with C-H = 0.93-0.96 Å. All H atoms were refined with isotropic displacement parameters (set to 1.2 times of the U eq of the parent atom).
The largest residual electron-density features are located in the region of Br5 and Br6. The highest peak is 0.84 Å from Br5 and the deepest hole is 0.82 Å from Br6.

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.