2-(4-Bromophenyl)-2-methyl-2,3-dihydroquinazolin-4(1H)-one

In the title compound, C15H13BrN2O, the pyrimidine ring adopts a skew boat conformation. The amino H atom forms an intermolecular hydrogen bond with the carbonyl O atom of an adjacent molecule, forming an inversion dimer. Another lone pair of electrons on the same carbonyl O atom acts as acceptor for another N—H⋯O intermolecular hydrogen bond with a neighbouring molecule, forming chains along the c axis.

In the title compound, C 15 H 13 BrN 2 O, the pyrimidine ring adopts a skew boat conformation. The amino H atom forms an intermolecular hydrogen bond with the carbonyl O atom of an adjacent molecule, forming an inversion dimer. Another lone pair of electrons on the same carbonyl O atom acts as acceptor for another N-HÁ Á ÁO intermolecular hydrogen bond with a neighbouring molecule, forming chains along the c axis.   Table 1 Hydrogen-bond geometry (Å , ).

Comment
The synthesis of quinazolinone derivatives has been the focus of great interest, because it was reported that its derivatives possessed a broad spectrum of biological properties. Some of these activities include antidepressant (Na et al., 2008), anticancer (Hwang et al., 2008, anti-inflammatory (Alagarsamy, et al., 2007), antibacterial (Alagarsamy et al., 2006), and antitubercular activity (Nandy et al., 2006). The title compound may be used as a new precursor for obtaining bioactive molecules. We report here the crystal structure of the title compound, (I).
In the title molecule the pyrimidine ring of the quinazolinone moiety is slightly distorted and adopts a skew conformation the basal plane of the pyrimidine ring is nearly parallel to the phenyl ring C3/C4/C5/C6/C7/C8, forming a dihedral angle of 4.5 (2)°, and is nearly perpendicular to another 4-bromophenyl ring, forming a dihedral angle of 82.2 (1)°.

Experimental
The title compound was prepared by the reaction of 2-aminobenzamide (0.272 g, 2 mmol) and 4'-bromoacetophenone (0.398 g, 2 mmol) in the presence of iodine (0.026 g) in tetrahydrofuran at 323 K for 6 h (yield 86%, m.p. 494-496 K). Crystals of (I) suitable for X-ray diffraction were obtained by slow evaporation of a dimethylformamide solution.

Refinement
The H atoms bonded to C atoms were included at geometrically idealized positions and refined in riding-model approximation with C-H = 0.93 and 0.96 Å, for aryl and methyl H atoms, respectively; the H atoms bonded to N atoms were allowed to refine. The U iso (H) were allowed at 1.2U eq (parent atoms). The final difference map was essentially featurless with the residual electron density located in the close proximity of the Br1 atom.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq Br1 0.39200 (