2,2,2-Tribromo-N-(4-chlorophenyl)acetamide

The crystal structure of the title compound, C8H5Br3ClNO, shows both intramolecular N—H⋯Br and intermolecular N—H⋯O hydrogen bonding. In the crystal, the molecules are packed into column-like chains in the c-axis direction via the N—H⋯O hydrogen bonds.

The crystal structure of the title compound, C 8 H 5 Br 3 ClNO, shows both intramolecular N-HÁ Á ÁBr and intermolecular N-HÁ Á ÁO hydrogen bonding. In the crystal, the molecules are packed into column-like chains in the c-axis direction via the N-HÁ Á ÁO hydrogen bonds.
The packing diagram of molecules showing the hydrogen bonds N1-H1N···O1 (Table 1) involved in the formation of molecular chains in the direction of the c-axis is given in Fig. 2.

Experimental
The title compound was prepared from 4-chloroaniline, 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 atom of the NH group was located in a difference map and later restrained to the distance N-H = 0.86 (5) Å. The other H atoms were positioned with idealized geometry using a riding model [C-H = 0.93 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 Br3 and Br2. The highest peak is 0.98 Å from Br3 and the deepest hole is 0.50 Å from Br2.  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.