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Acta Crystallogr Sect E Struct Rep Online. 2009 December 1; 65(Pt 12): o3134–o3135.
Published online 2009 November 21. doi:  10.1107/S1600536809048600
PMCID: PMC2972095

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

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 [triangle]); Kalluraya & Chimbalkar (2001 [triangle]); Kalluraya et al. (2001 [triangle]); Rai et al. (2008 [triangle]); Rathish et al. (2009 [triangle]); Tawab et al. (1960 [triangle]). For closely related structures, see: Goh et al. (2009a [triangle],b [triangle]). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986 [triangle]).

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Object name is e-65-o3134-scheme1.jpg

Experimental

Crystal data

  • C19H14BrN5O2
  • M r = 424.26
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o3134-efi1.jpg
  • 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 [triangle]) 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
  • Δρmax = 0.49 e Å−3
  • Δρmin = −0.30 e Å−3

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

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

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

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

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

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···Cg1iv = 3.5160 (11) Å, Cg2···Cg3ii = 3.6912 (11) Å and Cg2···Cg3iv = 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.

Refinement

All the H atoms were located from difference Fourier map [range of C—H = 0.91 (2) – 0.995 (19) Å] and allowed to refine freely. The reflections (001) and (011) were omitted as the intensities were affected by the beam-stop.

Figures

Fig. 1.
The molecular structure of (I), showing 50% probability displacement ellipsoids for non-H atoms and the atom-numbering scheme.
Fig. 2.
Part of the crystal structure of (I), viewed along the a axis, showing the dimers being linked into a 1-D chain along the b axis. Intermolecular contacts are shown as dashed lines.

Crystal data

C19H14BrN5O2Z = 2
Mr = 424.26F(000) = 428
Triclinic, P1Dx = 1.597 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 6.9709 (1) ÅCell parameters from 9873 reflections
b = 11.6500 (2) Åθ = 3.0–33.9°
c = 12.4365 (2) ŵ = 2.36 mm1
α = 114.969 (1)°T = 100 K
β = 103.303 (1)°Block, green
γ = 91.560 (1)°0.33 × 0.22 × 0.12 mm
V = 882.12 (2) Å3

Data collection

Bruker SMART APEXII CCD area-detector diffractometer3804 independent reflections
Radiation source: fine-focus sealed tube3431 reflections with I > 2σ(I)
graphiteRint = 0.026
[var phi] and ω scansθmax = 27.0°, θmin = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 2005)h = −8→8
Tmin = 0.510, Tmax = 0.760k = −14→14
28197 measured reflectionsl = −15→15

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.024Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.060All H-atom parameters refined
S = 1.05w = 1/[σ2(Fo2) + (0.0288P)2 + 0.5594P] where P = (Fo2 + 2Fc2)/3
3804 reflections(Δ/σ)max = 0.001
300 parametersΔρmax = 0.49 e Å3
0 restraintsΔρmin = −0.30 e Å3

Special details

Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1)K.
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 F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 2sigma(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 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 (Å2)

xyzUiso*/Ueq
Br10.32778 (3)0.891599 (17)1.068122 (15)0.02770 (7)
O1−0.3115 (2)0.02211 (12)0.64236 (12)0.0274 (3)
O2−0.0404 (2)−0.01117 (12)0.74511 (11)0.0258 (3)
N10.2287 (2)0.49488 (13)0.46957 (12)0.0175 (3)
N20.2681 (2)0.47661 (13)0.57546 (12)0.0177 (3)
N30.3203 (2)0.54232 (13)0.78176 (13)0.0191 (3)
N40.2364 (2)0.68890 (13)0.69321 (13)0.0182 (3)
N5−0.1294 (2)0.03714 (13)0.68034 (13)0.0205 (3)
C10.1859 (3)0.48220 (17)0.22862 (16)0.0224 (4)
C20.1604 (3)0.4683 (2)0.10980 (17)0.0282 (4)
C30.1682 (3)0.3501 (2)0.01564 (17)0.0300 (4)
C40.2012 (3)0.24641 (19)0.04084 (17)0.0275 (4)
C50.2323 (3)0.26060 (18)0.16071 (16)0.0236 (4)
C60.2252 (2)0.37903 (16)0.25600 (15)0.0201 (3)
C70.2607 (2)0.39338 (15)0.38231 (15)0.0176 (3)
C80.3349 (3)0.29328 (16)0.42148 (17)0.0228 (4)
C90.3406 (3)0.35347 (16)0.55889 (15)0.0191 (3)
C100.2129 (3)0.27153 (15)0.59130 (14)0.0175 (3)
C110.0070 (3)0.24832 (16)0.54497 (15)0.0188 (3)
C12−0.1072 (3)0.17094 (16)0.57339 (15)0.0191 (3)
C13−0.0101 (3)0.11782 (15)0.64817 (15)0.0178 (3)
C140.1942 (3)0.13677 (16)0.69325 (16)0.0211 (3)
C150.3060 (3)0.21486 (16)0.66433 (16)0.0213 (3)
C160.2747 (2)0.57397 (15)0.68747 (15)0.0165 (3)
C170.3326 (3)0.63670 (17)0.89244 (16)0.0207 (3)
C180.2999 (3)0.75881 (16)0.90934 (15)0.0204 (3)
C190.2496 (3)0.78065 (16)0.80562 (16)0.0201 (3)
H1A0.177 (3)0.563 (2)0.2909 (19)0.025 (5)*
H2A0.138 (4)0.540 (2)0.092 (2)0.038 (6)*
H3A0.154 (3)0.340 (2)−0.066 (2)0.037 (6)*
H4A0.206 (3)0.169 (2)−0.020 (2)0.024 (5)*
H5A0.257 (3)0.190 (2)0.178 (2)0.028 (5)*
H8A0.467 (3)0.2771 (19)0.4110 (19)0.024 (5)*
H8B0.250 (3)0.214 (2)0.378 (2)0.031 (6)*
H9A0.478 (3)0.3691 (17)0.6123 (17)0.013 (4)*
H11A−0.055 (3)0.2853 (18)0.4970 (18)0.019 (5)*
H12A−0.245 (3)0.1549 (19)0.5429 (19)0.024 (5)*
H14A0.258 (3)0.0991 (19)0.7416 (19)0.025 (5)*
H15A0.446 (3)0.2291 (19)0.6952 (19)0.025 (5)*
H17A0.372 (3)0.6149 (19)0.9598 (19)0.022 (5)*
H19A0.224 (3)0.8658 (19)0.8141 (18)0.019 (5)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br10.02884 (11)0.02882 (11)0.01659 (9)0.00509 (7)0.00679 (7)0.00134 (7)
O10.0263 (7)0.0275 (7)0.0323 (7)0.0020 (5)0.0112 (6)0.0154 (6)
O20.0386 (8)0.0213 (6)0.0223 (6)0.0044 (5)0.0086 (6)0.0139 (5)
N10.0171 (7)0.0197 (7)0.0145 (6)0.0012 (5)0.0029 (5)0.0070 (5)
N20.0231 (8)0.0155 (6)0.0160 (7)0.0037 (5)0.0070 (6)0.0073 (5)
N30.0199 (7)0.0202 (7)0.0180 (7)0.0023 (6)0.0060 (6)0.0087 (6)
N40.0185 (7)0.0179 (7)0.0174 (7)0.0043 (5)0.0047 (6)0.0068 (6)
N50.0302 (9)0.0147 (6)0.0173 (7)0.0036 (6)0.0107 (6)0.0055 (6)
C10.0190 (9)0.0260 (9)0.0173 (8)0.0058 (7)0.0023 (7)0.0061 (7)
C20.0244 (10)0.0390 (11)0.0209 (9)0.0122 (8)0.0031 (7)0.0140 (8)
C30.0235 (10)0.0459 (12)0.0152 (8)0.0112 (8)0.0028 (7)0.0091 (8)
C40.0202 (9)0.0321 (10)0.0173 (8)0.0036 (8)0.0049 (7)−0.0012 (8)
C50.0185 (9)0.0247 (9)0.0219 (9)0.0023 (7)0.0063 (7)0.0045 (7)
C60.0137 (8)0.0250 (9)0.0169 (8)0.0010 (6)0.0040 (6)0.0049 (7)
C70.0149 (8)0.0172 (7)0.0179 (8)−0.0004 (6)0.0050 (6)0.0051 (6)
C80.0315 (10)0.0164 (8)0.0246 (9)0.0043 (7)0.0156 (8)0.0086 (7)
C90.0212 (9)0.0161 (7)0.0209 (8)0.0036 (6)0.0081 (7)0.0078 (6)
C100.0236 (9)0.0140 (7)0.0149 (7)0.0033 (6)0.0077 (6)0.0050 (6)
C110.0225 (9)0.0184 (8)0.0179 (8)0.0055 (7)0.0056 (7)0.0099 (7)
C120.0204 (9)0.0187 (8)0.0183 (8)0.0046 (7)0.0060 (7)0.0075 (7)
C130.0252 (9)0.0137 (7)0.0153 (7)0.0028 (6)0.0085 (7)0.0057 (6)
C140.0278 (10)0.0197 (8)0.0179 (8)0.0066 (7)0.0054 (7)0.0103 (7)
C150.0194 (9)0.0216 (8)0.0212 (8)0.0032 (7)0.0030 (7)0.0092 (7)
C160.0136 (8)0.0174 (8)0.0173 (8)0.0013 (6)0.0048 (6)0.0064 (6)
C170.0191 (9)0.0255 (9)0.0180 (8)0.0028 (7)0.0059 (7)0.0095 (7)
C180.0176 (8)0.0222 (8)0.0152 (8)0.0020 (7)0.0049 (6)0.0023 (7)
C190.0187 (9)0.0192 (8)0.0204 (8)0.0046 (7)0.0051 (7)0.0067 (7)

Geometric parameters (Å, °)

Br1—C181.8863 (16)C5—H5A0.94 (2)
O1—N51.228 (2)C6—C71.468 (2)
O2—N51.2337 (19)C7—C81.504 (2)
N1—C71.292 (2)C8—C91.539 (2)
N1—N21.3886 (19)C8—H8A0.97 (2)
N2—C161.365 (2)C8—H8B0.95 (2)
N2—C91.481 (2)C9—C101.519 (2)
N3—C171.332 (2)C9—H9A0.995 (19)
N3—C161.346 (2)C10—C111.391 (2)
N4—C191.334 (2)C10—C151.393 (2)
N4—C161.348 (2)C11—C121.389 (2)
N5—C131.471 (2)C11—H11A0.91 (2)
C1—C21.384 (3)C12—C131.387 (2)
C1—C61.399 (3)C12—H12A0.93 (2)
C1—H1A0.95 (2)C13—C141.379 (3)
C2—C31.394 (3)C14—C151.390 (2)
C2—H2A0.96 (2)C14—H14A0.93 (2)
C3—C41.383 (3)C15—H15A0.94 (2)
C3—H3A0.95 (2)C17—C181.381 (3)
C4—C51.392 (3)C17—H17A0.96 (2)
C4—H4A0.91 (2)C18—C191.388 (2)
C5—C61.400 (2)C19—H19A0.98 (2)
C7—N1—N2107.71 (14)N2—C9—C10113.23 (14)
C16—N2—N1121.50 (13)N2—C9—C8101.32 (13)
C16—N2—C9123.73 (14)C10—C9—C8113.11 (14)
N1—N2—C9113.65 (13)N2—C9—H9A110.2 (10)
C17—N3—C16115.56 (15)C10—C9—H9A107.2 (10)
C19—N4—C16115.45 (14)C8—C9—H9A111.9 (10)
O1—N5—O2123.49 (14)C11—C10—C15119.99 (15)
O1—N5—C13118.57 (14)C11—C10—C9121.01 (15)
O2—N5—C13117.94 (15)C15—C10—C9118.95 (15)
C2—C1—C6120.44 (17)C12—C11—C10120.27 (16)
C2—C1—H1A118.6 (12)C12—C11—H11A119.2 (12)
C6—C1—H1A121.0 (12)C10—C11—H11A120.5 (12)
C1—C2—C3120.15 (19)C13—C12—C11118.28 (16)
C1—C2—H2A120.0 (14)C13—C12—H12A120.8 (12)
C3—C2—H2A119.8 (14)C11—C12—H12A121.0 (12)
C4—C3—C2119.95 (17)C14—C13—C12122.77 (15)
C4—C3—H3A119.4 (14)C14—C13—N5118.41 (15)
C2—C3—H3A120.6 (14)C12—C13—N5118.82 (15)
C3—C4—C5120.16 (17)C13—C14—C15118.17 (16)
C3—C4—H4A120.9 (13)C13—C14—H14A122.0 (13)
C5—C4—H4A118.9 (13)C15—C14—H14A119.8 (13)
C4—C5—C6120.28 (18)C14—C15—C10120.49 (17)
C4—C5—H5A120.2 (13)C14—C15—H15A119.0 (12)
C6—C5—H5A119.5 (13)C10—C15—H15A120.5 (12)
C1—C6—C5118.96 (16)N3—C16—N4127.09 (15)
C1—C6—C7121.19 (15)N3—C16—N2114.49 (14)
C5—C6—C7119.85 (16)N4—C16—N2118.43 (14)
N1—C7—C6121.79 (16)N3—C17—C18122.24 (16)
N1—C7—C8114.40 (15)N3—C17—H17A115.3 (12)
C6—C7—C8123.81 (15)C18—C17—H17A122.4 (12)
C7—C8—C9102.87 (13)C17—C18—C19117.58 (15)
C7—C8—H8A112.2 (12)C17—C18—Br1121.08 (13)
C9—C8—H8A110.4 (12)C19—C18—Br1121.33 (13)
C7—C8—H8B112.8 (13)N4—C19—C18122.05 (16)
C9—C8—H8B111.1 (13)N4—C19—H19A118.1 (11)
H8A—C8—H8B107.5 (18)C18—C19—H19A119.8 (11)
C7—N1—N2—C16170.72 (14)C15—C10—C11—C121.4 (2)
C7—N1—N2—C92.42 (18)C9—C10—C11—C12178.62 (15)
C6—C1—C2—C31.8 (3)C10—C11—C12—C13−0.2 (2)
C1—C2—C3—C40.1 (3)C11—C12—C13—C14−1.2 (2)
C2—C3—C4—C5−1.8 (3)C11—C12—C13—N5179.18 (14)
C3—C4—C5—C61.6 (3)O1—N5—C13—C14178.59 (15)
C2—C1—C6—C5−1.9 (3)O2—N5—C13—C14−0.9 (2)
C2—C1—C6—C7177.49 (16)O1—N5—C13—C12−1.8 (2)
C4—C5—C6—C10.2 (3)O2—N5—C13—C12178.73 (14)
C4—C5—C6—C7−179.20 (16)C12—C13—C14—C151.5 (3)
N2—N1—C7—C6177.49 (14)N5—C13—C14—C15−178.92 (15)
N2—N1—C7—C8−2.15 (19)C13—C14—C15—C10−0.3 (3)
C1—C6—C7—N110.4 (2)C11—C10—C15—C14−1.1 (2)
C5—C6—C7—N1−170.23 (16)C9—C10—C15—C14−178.41 (15)
C1—C6—C7—C8−170.01 (16)C17—N3—C16—N4−1.6 (2)
C5—C6—C7—C89.4 (2)C17—N3—C16—N2178.34 (14)
N1—C7—C8—C91.11 (19)C19—N4—C16—N31.4 (2)
C6—C7—C8—C9−178.52 (15)C19—N4—C16—N2−178.54 (14)
C16—N2—C9—C1068.9 (2)N1—N2—C16—N3−178.10 (14)
N1—N2—C9—C10−123.07 (15)C9—N2—C16—N3−11.0 (2)
C16—N2—C9—C8−169.64 (15)N1—N2—C16—N41.8 (2)
N1—N2—C9—C8−1.64 (17)C9—N2—C16—N4168.92 (14)
C7—C8—C9—N20.35 (16)C16—N3—C17—C180.3 (2)
C7—C8—C9—C10121.86 (15)N3—C17—C18—C191.0 (3)
N2—C9—C10—C1149.0 (2)N3—C17—C18—Br1−177.75 (12)
C8—C9—C10—C11−65.5 (2)C16—N4—C19—C180.1 (2)
N2—C9—C10—C15−133.70 (16)C17—C18—C19—N4−1.2 (3)
C8—C9—C10—C15111.76 (18)Br1—C18—C19—N4177.53 (13)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C8—H8B···O2i0.95 (2)2.41 (2)3.352 (2)176.0 (17)
C11—H11A···N4ii0.92 (2)2.56 (2)3.431 (2)160.5 (18)
C19—H19A···O2iii0.98 (2)2.58 (2)3.412 (3)143.3 (17)

Symmetry codes: (i) −x, −y, −z+1; (ii) −x, −y+1, −z+1; (iii) x, y+1, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: TK2577).

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