N-(2-bromophenyl)acetamide

The dihedral angle between the mean planes of the benzene ring (atoms C1–C6) and the N1/O1/C7/C8 side-chain grouping in (I) is 42.75 (14) . This is intermediate between the situation in acetanilide [i.e. (I) without the Br atom], C8H9NO (Brown, 1966; Wasserman et al., 1985), where the aromatic ring and side chain are twisted by 17.6 , and N-methylacetanilide, C9H11NO (Pederson, 1967), where the two corresponding groups of atoms are constrained by symmetry to be perpendicular. The Car—N (ar = aromatic) bond distances are almost identical in (I) and acetanilide (Brown, 1966), being 1.418 (4) and 1.417 (2) A respectively, as are the Cc—N (c = carbonyl) distances, at 1.358 (4) and 1.355 (2) A, respectively. The equivalent distances in N-methylacetanilide (Pederson, 1967), where any electronic conjugation between the benzene ring and amide group is presumably impossible because of their perpendicular orientation, are distinctly different, with Car—N much longer at 1.474 A and Cc—N significantly shorter at 1.325 A. The bond angle sum about N1 in (I) is 360.0 , suggesting that this atom is essentially sp-hybridized. All the other geometrical parameters for (I) lie within their expected ranges (Allen et al., 1995). The crystal packing in (I) is influenced by an N—H O hydrogen bond (Table 1 and Fig. 2) that links the molecules into chains propagating along [100]. There are no – stacking interactions in (I). The packing is shown in Fig. 3.