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

K N Venugopala; Susanta K Nayak; Bharti Odhav

doi:10.1107/S1600536813006296

. 2013 Mar 9;69(Pt 4):o518–o519. doi: 10.1107/S1600536813006296

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

K N Venugopala ^a,^*, Susanta K Nayak ^b,^*, Bharti Odhav ^a

PMCID: PMC3629576 PMID: 23634063

Abstract

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.

Related literature

For a study of chloride salts of dihydropyrimidine derivatives and their anti-tubercular activity, see: Venugopala, Nayak, Pillay et al. (2012 ▶). For the crystal structures of dihydropyrimidine derivatives, see: Venugopala, Nayak & Odhav (2012 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶).

Experimental

Crystal data

C₁₉H₁₈BrClN₃O₂ ⁺·Cl⁻
M _r = 471.17
Monoclinic,
a = 13.2691 (15) Å
b = 11.0965 (12) Å
c = 14.9545 (17) Å
β = 114.181 (3)°
V = 2008.7 (4) Å³
Z = 4
Mo Kα radiation
μ = 2.33 mm⁻¹
T = 100 K
0.08 × 0.05 × 0.03 mm

Data collection

Bruker Kappa DUO APEXII diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2008 ▶) T _min = 0.835, T _max = 0.933
10242 measured reflections
3919 independent reflections
2511 reflections with I > 2σ(I)
R _int = 0.067

Refinement

R[F ² > 2σ(F ²)] = 0.044
wR(F ²) = 0.096
S = 0.95
3919 reflections
246 parameters
H-atom parameters constrained
Δρ_max = 0.42 e Å⁻³
Δρ_min = −0.40 e Å⁻³

Data collection: APEX2 (Bruker, 2008 ▶); cell refinement: SAINT (Bruker, 2008 ▶); data reduction: SAINT; 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 ▶).

Supplementary Material

Click here for additional data file.^{(25.6KB, cif)}

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536813006296/pv2621sup1.cif

e-69-0o518-sup1.cif^{(25.6KB, cif)}

Click here for additional data file.^{(188.2KB, hkl)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536813006296/pv2621Isup2.hkl

e-69-0o518-Isup2.hkl^{(188.2KB, hkl)}

Click here for additional data file.^{(7KB, cml)}

Supplementary material file. DOI: 10.1107/S1600536813006296/pv2621Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯Cl2	0.88	2.34	3.136 (3)	151
N2—H2⋯Cl2ⁱ	0.88	2.41	3.179 (3)	146
N3—H3⋯Cl2ⁱ	0.88	2.39	3.191 (3)	151
C5—H5A⋯O2	0.98	2.22	2.897 (5)	125
C15—H15⋯O2ⁱⁱ	0.95	2.42	3.197 (5)	139
C18—H18⋯Cl2ⁱⁱⁱ	0.95	2.81	3.702 (4)	156

Open in a new tab

Symmetry codes: (i) Inline graphic ; (ii) ; (iii) .

Acknowledgments

The authors thank Durban University of Technology for facilities. KNV thanks the NRF South Africa for a DST/NRF Innovation Postdoctoral Fellowship.

supplementary crystallographic information

Comment

We have recently reported that the chloride salts of dihydropyrimidine derivatives exhibit anti-tubercular activity (Venugopala, Nayak, Pillay et al. 2012). In continuation of our work in this field and on the crystal structures of dihydropyrimidine derivatives (Venugopala, Nayak & Odhav, 2012), we now report in this article, the crystal structure of the title compound.

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 (Venugopala, Nayak &Odhav, 2012).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).

In the crystal structure, Cl2 is hydrogen bonded to N2 and N3 forming six membered rings in R₂¹(6) motif (Bernstein et al.,1995). This Cl2 is also involved in a hydrogen bond (C18—H18···Cl2) with a molecule lying about an inversion center thus resulting in dimers. In addition, N1—H1···Cl2 interactions link the dimers into chains in the (1 0 1) direction. C15—H15···O2 interactions also result in macrocyclic rings about inversion centers resulting in dimers. Finally, a Br1···Cl1^* short contact (3.482 (2) Å, symmetry code ^*: x - 1/2, -y + 1/2, z + 1/2) interlinks the hydrogen bonded chains along the b axis.

Experimental

A mixture of methyl-2-chloro-4-(4-chlorophenyl)-6-methyl-1,4- dihydropyrimidine-5-carboxylate (1 mmol) and 4-bromoaniline (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.