2-Bromo-N-(2-chlorophenyl)acetamide

The conformation of the N—H bond in the structure of the title compound, C8H7BrClNO, is syn to the 2-chloro substituent in the aniline ring and anti to both the C=O and C—Br bonds in the side chain, similar to that observed in 2-chloro-N-(2-chlorophenyl)acetamide. In the crystal, molecules are linked into chains along the a axis by N—H⋯O hydrogen bonds. These chains are in turn linked into pairs, in the form of columns, through much weaker C—H⋯Cl and Br⋯Br [4.3027 (3) Å] interactions.

The conformation of the N-H bond in the structure of the title compound, C 8 H 7 BrClNO, is syn to the 2-chloro substituent in the aniline ring and anti to both the C O and C-Br bonds in the side chain, similar to that observed in 2-chloro-N-(2-chlorophenyl)acetamide. In the crystal, molecules are linked into chains along the a axis by N-HÁ Á ÁO hydrogen bonds. These chains are in turn linked into pairs, in the form of columns, through much weaker C-HÁ Á ÁCl and BrÁ Á ÁBr

Comment
As part of a study of the effect of the ring and the side chain substituents on the structures of N-aromatic amides (Gowda et al., 2007a,b,c), in the present work we report the structure of 2-bromo-N-(2-chlorophenyl)acetamide (I). The conformation of the N-H bond in the structure is syn to the ortho-Cl substituent in the aniline ring and anti to both the C=O and C-Br bonds in the side chain ( Fig. 1), similar to that observed in 2-chloro-N-(2-chlorophenyl)acetamide (Gowda et al., 2007a) and other side chain substituted aromatic amides.
The packing diagram in Fig. 2 shows the formation of molecular chains in the direction of the a axis through the N1-H1N···O1 H-bonds (Table 1). These chains are in turn linked into pairs, in the form of strips, through much weaker C-H···Cl and Br···Br interactions.

Experimental
The title compound was prepared from 2-chloroaniline and bromoacetylchloride according to the literature method (Gowda et al., 2003). The purity of the compound was checked by determining its melting point, and further characterized by recording its infrared spectra (Gowda et al., 2003). Single crystals of the title compound used for X-ray diffraction studies were obtained by slow evaporation of an ethanolic solution at room temperature.

Refinement
The N-bound H atom was located in a difference map and refined with a restrained geometry (N-H= 0.86 (2) Å). The other H atoms were positioned with idealized geometry using a riding model [C-H = 0.93-0.97 Å]. All H atoms were refined with isotropic displacement parameters (set to 1.2 times of the U eq of the parent atom). Fig. 1. Molecular structure of (I), showing the atom labelling scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are represented as small spheres of arbitrary radii. Fig. 2. Molecular packing of (I) showing chains, with hydrogen bonds shown as dashed lines.

Figures
The unit cell is shown as "broken" along the c direction, for completeness.