2-Bromo-2-methyl-N-(4-nitrophenyl)propanamide

The title compound, C10H11BrN2O3, exhibits a small twist between the amide residue and benzene ring [the C—N—C—C torsion angle = 12.7 (4)°]. The crystal structure is stabilized by weak N—H⋯O, C—H⋯Br and C—H⋯O interactions. These lead to supramolecular layers in the bc plane.

The title compound, C 10 H 11 BrN 2 O 3 , exhibits a small twist between the amide residue and benzene ring [the C-N-C-C torsion angle = 12.7 (4) ]. The crystal structure is stabilized by weak N-HÁ Á ÁO, C-HÁ Á ÁBr and C-HÁ Á ÁO interactions. These lead to supramolecular layers in the bc plane.
RMF is grateful to the Spanish Research Council (CSIC) for the use of a free-of-charge licence to the Cambridge Structural Database. RMF and FZ also thank the Universidad del Valle, Colombia, and the Instituto de Química de Sã o Carlos, USP, Brasil for partial financial support. RLAH thanks CNPq for partial financial support.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: TK2720). most initiators for ATRP processes are alkyl halides (Matyjaszewski & Xia, 2001). The C4-N1-C5-C6 torsion angle is 12.7 (4)°, indicating a small twist between the benzene ring and the amide. An intramolecular C-H···O interaction is observed (see Table 1).

Experimental
The initial reagents were purchased from Aldrich Chemical Co. and were used as received. In a 100 mL round bottom flask 4-nitroaniline (3.258 mmol, 0.450 g), triethylamine (0.653 mmol, 0.066 g) were mixed, then a solution of 2-bromo isobuturyl bromide (0.704 g) in anhydrous THF (5 mL) was added drop wise, under an argon stream. The reaction was carried out in a dry bag overnight under magnetic stirring. The solid was filtered off and dichloromethane (20 mL) added to the organic phase which was washed with brine (40 mL) followed by water (10 mL). The solution was concentrated at low pressure affording colourless crystals and recrystalized from a solution of hexane and ethyl acetate (80:20). M. pt. 356 (1) K.

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 > 2sigma(F 2 ) is used only for calculating R-factors(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.