2-(4-Bromoanilino)-6-(4-chlorophenyl)-5-methoxycarbonyl-4-methyl-3,6-dihydropyrimidin-1-ium chloride

In the title molecular salt, C19H18BrClN3O2 +·Cl−, the dihedral angles between the pyrimidine ring and the chlorobenzene and bromobenzene rings are 72.4 (2) and 45.5 (2)°, respectively. The dihedral angle between the chlorobenzene and bromobenzene rings is 27.5 (2)°. The conformation of the molecule is stabilized by an intramolecular C—H⋯O interaction. In the crystal, the anion and cation are linked by an N—H⋯Cl hydrogen bond. Pairs of weak C—H⋯O and C—H⋯Cl hydrogen bonds form inversion dimers. Further N—H⋯Cl hydrogen bonds form R 2 1(6) motifs and link the dimers into chains along [101]. Br⋯Cl short contacts [3.482 (2) Å] interlink the hydrogen-bonded chains along the b-axis direction.

In the title molecular salt, C 19 H 18 BrClN 3 O 2 + ÁCl À , the dihedral angles between the pyrimidine ring and the chlorobenzene and bromobenzene rings are 72.4 (2) and 45.5 (2) , respectively. The dihedral angle between the chlorobenzene and bromobenzene rings is 27.5 (2) . The conformation of the molecule is stabilized by an intramolecular C-HÁ Á ÁO interaction. In the crystal, the anion and cation are linked by an N-HÁ Á ÁCl hydrogen bond. Pairs of weak C-HÁ Á ÁO and C-HÁ Á ÁCl hydrogen bonds form inversion dimers. Further N-HÁ Á ÁCl hydrogen bonds form R 2 1 (6) motifs and link the dimers into chains along [101]. BrÁ Á ÁCl short contacts [3.482 (2) Å ] interlink the hydrogen-bonded chains along the b-axis direction.
The bond distances and angles in the title compound ( Fig. 1) agree very well with the corresponding bond distances and angles reported in a closely related compound .The dihedral angles between the planes of 4-chlorophenyl and 4-bromophenyl rings with the plane of the six-membered pyrimidine ring are 72.4 (2)° and 45.5 (2)°, respectively. The conformation of the title molecule is stabilized by intramolecular C5-H5···O2 interactions.
The crystal structure is stabilized by the N-H···Cl hydrogen bonds and further consolidated by weak C-H···O and C-H···Cl hydrogen bonding interactions (Table 1 & Fig. 2).

Experimental
A mixture of methyl-2-chloro-4-(4-chlorophenyl)-6-methyl-1,4-dihydropyrimidine-5-carboxylate (1 mmol) and 4bromoaniline (1 mmol) in 2-propanol (5 mL) was refluxed for 16 h. The reaction was monitored by TLC. The reaction medium was cooled to room temperature and the product was filtered, washed with cold 2-propanol and dried to obtain the crude product. The product was purified by recrystallization using ethanol to yield 66% yield of product which was pale yellow amorphous solid (m.p. 500 (2) K). Crystals suitable for single-crystal X-ray analysis were obtained using acetone as a solvent using slow evaporation at room temperature.

Refinement
All H atoms were positioned geometrically with N-H = 0.88 Å, C-H = 0.95-1.00 Å and refined using a riding model with U iso (H) = 1.2 U eq (C/N)except for the methyl group where U iso (H) = 1.5 U eq (C).

Computing details
Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: PLATON (Spek, 2009) and PARST (Nardelli, 1995).    where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.42 e Å −3 Δρ min = −0.40 e Å −3 Special details Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s 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 > 2σ(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.

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