5-Bromo-2-[5-(4-nitro­phen­yl)-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl]pyrimidine

Jia Hao Goh; Hoong-Kun Fun; Adithya Adhikari; B Kalluraya

doi:10.1107/S1600536809048600

. 2009 Nov 21;65(Pt 12):o3134–o3135. doi: 10.1107/S1600536809048600

5-Bromo-2-[5-(4-nitrophenyl)-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl]pyrimidine

Jia Hao Goh ^a,^‡, Hoong-Kun Fun ^a,^*,^§, Adithya Adhikari ^b, B Kalluraya ^b

PMCID: PMC2972095 PMID: 21578856

Abstract

In the title pyrazoline compound, C₁₉H₁₄BrN₅O₂, the essentially planar pyrazoline and pyrimidine rings [maximum deviations = 0.013 (1) and 0.009 (1) Å, respectively] are inclined slightly to one another, making a dihedral angle of 10.81 (10)°. The nitrobenzene unit is almost perpendicular to the attached pyrazoline ring, as indicated by the dihedral angle of 84.61 (8)°. In the crystal structure, intermolecular C—H⋯N contacts link the molecules into dimers in an antiparallel manner. These dimers are further linked into one-dimensional chains along the b axis via C—H⋯O contacts. The crystal structure is consolidated by three different intermolecular π–π interactions [range of centroid–centroid distances = 3.5160 (11)–3.6912 (11) Å].

Related literature

For general background to and applications of the title compound, see: Hegde et al. (2006 ▶); Kalluraya & Chimbalkar (2001 ▶); Kalluraya et al. (2001 ▶); Rai et al. (2008 ▶); Rathish et al. (2009 ▶); Tawab et al. (1960 ▶). For closely related structures, see: Goh et al. (2009a ▶,b ▶). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986 ▶). graphic file with name e-65-o3134-scheme1.jpg

Experimental

Crystal data

C₁₉H₁₄BrN₅O₂
M _r = 424.26
Triclinic,
a = 6.9709 (1) Å
b = 11.6500 (2) Å
c = 12.4365 (2) Å
α = 114.969 (1)°
β = 103.303 (1)°
γ = 91.560 (1)°
V = 882.12 (2) Å³
Z = 2
Mo Kα radiation
μ = 2.36 mm⁻¹
T = 100 K
0.33 × 0.22 × 0.12 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T _min = 0.510, T _max = 0.760
28197 measured reflections
3804 independent reflections
3431 reflections with I > 2σ(I)
R _int = 0.026

Refinement

R[F ² > 2σ(F ²)] = 0.024
wR(F ²) = 0.060
S = 1.05
3804 reflections
300 parameters
All H-atom parameters refined
Δρ_max = 0.49 e Å⁻³
Δρ_min = −0.30 e Å⁻³

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: SAINT (Bruker, 2005 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809048600/tk2577sup1.cif

e-65-o3134-sup1.cif^{(21KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809048600/tk2577Isup2.hkl

e-65-o3134-Isup2.hkl^{(186.5KB, hkl)}

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
C8—H8B⋯O2ⁱ	0.95 (2)	2.41 (2)	3.352 (2)	176.0 (17)
C11—H11A⋯N4ⁱⁱ	0.92 (2)	2.56 (2)	3.431 (2)	160.5 (18)
C19—H19A⋯O2ⁱⁱⁱ	0.98 (2)	2.58 (2)	3.412 (3)	143.3 (17)

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

Acknowledgments

HKF and JHG thank Universiti Sains Malaysia (USM) for the Research University Golden Goose grant (No. 1001/PFIZIK/811012). JHG also thanks USM for the award of a USM fellowship.

supplementary crystallographic information

Comment

Pyrazoles and pyrazoline derivatives are an important class of heterocyclic compounds (Rai et al., 2008; Hegde et al., 2006). The addition of aliphatic diazo compounds to olefins leads to pyrazolines. Also, the addition of hydrazine or its derivatives to α, β-unsaturated aldehydes or ketones yields pyrazoline (Kalluraya & Chimbalkar, 2001). Pyrazoline derivatives have been found to possess potential anti-pyretic, analgesic (Tawab et al., 1960), anti-inflammatory (Rathish et al., 2009), and anti-microbial (Kalluraya et al., 2001) properties. In the present work, an X-ray crystal structure analysis has been undertaken in order to determine the 3D chemical structure and also the crystal packing of the molecules. We herein report the synthesis and crystal structure of the title compound, (I).

In (I), Fig. 1, the pyrazoline (C7-C9/N1/N2) and pyrimidine (C16-C19/N3/N4) rings are essentially planar, with maximum deviations of 0.013 (1) and 0.009 (1) Å, respectively, for atoms N1 and C16. These two rings are slightly inclined to one another, making a dihedral angle of 10.81 (10)°. The nitrobenzene moiety is almost perpendicular to the attached pyrazoline ring, as indicated by the dihedral angle formed between the mean plane through C10-C15/N5/O1/O2 and the pyrazoline ring of 84.61 (8)°. The bond lengths and angles are consistent with those closely related structures (Goh et al., 2009a,b).

In the crystal structure (Fig. 2), intermolecular C11—H11A···N4 contacts (Table 1) link the molecules into dimers in an anti-parallel manner. These dimers are further linked into a 1-D chain along the b axis by intermolecular C8—H8B···O2 and C19—H19A···O2 contacts (Table 1). The crystal structure is consolidated by three different weak π–π interactions involving the pyrazoline (Cg1), pyrimidine (Cg2) and C1-C6 benzene (Cg3) rings [Cg1···Cg1^iv = 3.5160 (11) Å, Cg2···Cg3ⁱⁱ = 3.6912 (11) Å and Cg2···Cg3^iv = 3.5779 (11) Å, respectively; (ii) -x, 1-y, 1-z and (iv) 1-x, 1-y, 1-z].

Experimental

A mixture of 5-bromo-2-hydrazinopyrimidine (0.01 mol) and 3-(4-nitrophenyl)-1-phenyl-prop-2-en-1-one (0.01 mol) was taken in acetic acid (20 ml), and two drops of concentrated H₂SO₄ added. The mixture was refluxed for 4 h. The precipitated solids were filtered, dried and recrystallized from ethanol. The single crystals were obtained from a mixture of ethanol and DMF by slow evaporation.