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Acta Crystallogr Sect E Struct Rep Online. 2009 June 1; 65(Pt 6): o1396.
Published online 2009 May 23. doi:  10.1107/S1600536809018352
PMCID: PMC2969633

(Z)-3-(9-Anthr­yl)-1-(4-bromo­phen­yl)-2-(4-nitro-1H-imidazol-1-yl)prop-2-en-1-one

Abstract

In the title mol­ecule, C26H16BrN3O3, the anthracene and benzene mean planes make dihedral angles of 63.79 (2) and 14.67 (2)°, respectively, with the plane of the imidazole ring. In the crystal structure, weak inter­molecular C—H(...)O hydrogen bonds link mol­ecules to form centrosymmetric dimers. Weak π–π stacking inter­actions, with centroid–centroid distances of 3.779 (2) and 3.826 (2) Å, supply additional stabilization. The crystal packing also exhibits short inter­molecular contacts between the nitro groups and Br atoms [Br(...)O = 3.114 (2) Å].

Related literature

For the crystal structure of the chloro analog of the title compound, see: Wang et al. (2009 [triangle]). For general background on the pharmacological activities of chalcones, see: Corréa et al. (2001 [triangle]); Jasinski et al. (2009 [triangle]); Nielsen et al. (1998 [triangle]); Vogel et al. (2008 [triangle]). For the synthetic details, see: Erhardt et al. (1985 [triangle]); Kranz et al. (1980 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o1396-scheme1.jpg

Experimental

Crystal data

  • C26H16BrN3O3
  • M r = 498.33
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1396-efi1.jpg
  • a = 8.1438 (11) Å
  • b = 11.0916 (14) Å
  • c = 12.7979 (17) Å
  • α = 78.146 (2)°
  • β = 86.193 (2)°
  • γ = 70.768 (2)°
  • V = 1068.2 (2) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 1.96 mm−1
  • T = 292 K
  • 0.13 × 0.12 × 0.10 mm

Data collection

  • Bruker SMART APEX CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.775, T max = 0.828
  • 6422 measured reflections
  • 4315 independent reflections
  • 3095 reflections with I > 2σ(I)
  • R int = 0.019

Refinement

  • R[F 2 > 2σ(F 2)] = 0.044
  • wR(F 2) = 0.116
  • S = 1.02
  • 4315 reflections
  • 298 parameters
  • H-atom parameters constrained
  • Δρmax = 0.56 e Å−3
  • Δρmin = −0.67 e Å−3

Data collection: SMART (Bruker, 2001 [triangle]); cell refinement: SAINT-Plus (Bruker, 2001 [triangle]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: PLATON.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809018352/lh2825sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809018352/lh2825Isup2.hkl

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

Acknowledgments

We thank the Southwest University (grant Nos. SWUB2006018, XSGX0602 and SWUF2007023) and the Natural Science Foundation of Chongqing (grant No. 2007BB5369) for financial support.

supplementary crystallographic information

Comment

Chalcones and their derivatives have been reported responsible for a variety of pharmacological activities, including antibacterial, antifungal, anti-leishmanial, antimalarial, analgesic, anti-inflammatory and chemopreventive ones (Corréa et al., 2001; Jasinski et al., 2009; Simon et al., 1998; Vogel et al., 2008). Due to these varied applications, we have synthesized the title compound and report its crystal structure.

In the molecular structure of the title compound (I) (Fig. 1), the dihedral angle between the anthracene unit and imidazole ring is 63.79 (2) ° and that between the imidazole ring and benzene ring is 14.67 (2) °. In the crystal structure, weak intermolecular C—H···O hydrogen bonds link molecules to form centrosymmetric dimers (Fig. 2). Weak π–π staking interactions, with centroid to centroid distances of 3.779 (2) and 3.826 (2)Å supply additional stabilization.

Experimental

Compound (I) was synthesized according to the procedure of Erhardt et al. (1985); Kranz et al. (1980). A crystal suitable for X-ray analysis was grown from a chloroform and acetone solution of (I) by slow evaporation at room temperature.

Refinement

H ydrogen atoms were placed in idealized positions with C—H = 0.93Å and Uiso(H) = 1.2Ueq(C).

Figures

Fig. 1.
The molecular structure of (I), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
Fig. 2.
Part of the crystal structure of (I). Hydrogen bonds are shown as dashed lines.

Crystal data

C26H16BrN3O3Z = 2
Mr = 498.33F(000) = 504
Triclinic, P1Dx = 1.549 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.1438 (11) ÅCell parameters from 2344 reflections
b = 11.0916 (14) Åθ = 2.3–26.9°
c = 12.7979 (17) ŵ = 1.96 mm1
α = 78.146 (2)°T = 292 K
β = 86.193 (2)°Block, orange
γ = 70.768 (2)°0.13 × 0.12 × 0.10 mm
V = 1068.2 (2) Å3

Data collection

Bruker SMART APEX CCD area-detector diffractometer4315 independent reflections
Radiation source: fine focus sealed Siemens Mo tube3095 reflections with I > 2σ(I)
graphiteRint = 0.019
0.3° wide ω exposures scansθmax = 26.5°, θmin = 2.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −8→10
Tmin = 0.775, Tmax = 0.828k = −13→13
6422 measured reflectionsl = −16→15

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.044H-atom parameters constrained
wR(F2) = 0.116w = 1/[σ2(Fo2) + (0.0524P)2 + 0.6665P] where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max = 0.008
4315 reflectionsΔρmax = 0.56 e Å3
298 parametersΔρmin = −0.67 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0078 (11)

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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 > σ(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
Br10.93749 (6)0.89457 (4)0.12755 (3)0.06983 (18)
C10.4551 (4)0.4031 (3)0.3854 (2)0.0356 (6)
C20.3193 (4)0.4914 (3)0.4320 (2)0.0406 (7)
C30.2357 (4)0.6217 (3)0.3799 (3)0.0496 (8)
H30.26990.65060.31110.060*
C40.1080 (5)0.7050 (4)0.4276 (4)0.0691 (11)
H40.05650.79020.39170.083*
C50.0521 (5)0.6637 (5)0.5312 (4)0.0740 (13)
H5−0.03420.72240.56390.089*
C60.1223 (5)0.5405 (5)0.5832 (3)0.0647 (11)
H60.08190.51440.65090.078*
C70.2583 (4)0.4483 (4)0.5363 (2)0.0510 (9)
C80.3318 (5)0.3209 (4)0.5877 (3)0.0570 (10)
H80.28930.29300.65430.068*
C90.4663 (5)0.2335 (4)0.5435 (3)0.0545 (9)
C100.5444 (7)0.1041 (4)0.5990 (3)0.0804 (14)
H100.50070.07650.66530.096*
C110.6795 (8)0.0206 (5)0.5582 (4)0.0943 (17)
H110.7273−0.06420.59570.113*
C120.7504 (7)0.0613 (4)0.4575 (4)0.0792 (13)
H120.84610.00340.43050.095*
C130.6790 (5)0.1839 (3)0.4007 (3)0.0538 (9)
H130.72700.20920.33530.065*
C140.5326 (4)0.2738 (3)0.4394 (2)0.0415 (7)
C150.5261 (4)0.4522 (3)0.2830 (2)0.0327 (6)
H150.56260.52350.28200.039*
C160.5458 (4)0.4098 (2)0.1916 (2)0.0308 (6)
C170.3147 (4)0.3086 (3)0.1964 (2)0.0391 (7)
H170.22150.37300.21850.047*
C180.5712 (5)0.1936 (3)0.1475 (3)0.0456 (7)
H180.68860.16980.12960.055*
C190.3157 (5)0.1937 (3)0.1754 (2)0.0448 (8)
C200.6441 (4)0.4580 (3)0.0995 (2)0.0322 (6)
C210.7038 (4)0.5703 (3)0.1060 (2)0.0332 (6)
C220.8822 (4)0.5456 (3)0.1056 (2)0.0422 (7)
H220.95690.46280.10140.051*
C230.9499 (4)0.6436 (3)0.1113 (3)0.0490 (8)
H231.06960.62670.11220.059*
C240.8383 (4)0.7651 (3)0.1157 (2)0.0438 (7)
C250.6602 (4)0.7937 (3)0.1138 (2)0.0426 (7)
H250.58610.87750.11550.051*
C260.5943 (4)0.6947 (3)0.1094 (2)0.0389 (7)
H260.47460.71210.10870.047*
N10.4811 (3)0.3085 (2)0.17774 (18)0.0342 (5)
N20.4740 (4)0.1210 (2)0.1464 (2)0.0515 (7)
N30.1680 (5)0.1482 (3)0.1818 (3)0.0663 (9)
O10.1909 (5)0.0414 (3)0.1602 (3)0.1002 (11)
O20.0289 (5)0.2194 (4)0.2088 (3)0.0920 (10)
O30.6822 (3)0.4034 (2)0.02424 (17)0.0464 (5)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br10.0870 (3)0.0579 (2)0.0872 (3)−0.0537 (2)0.0032 (2)−0.01466 (19)
C10.0423 (17)0.0457 (16)0.0284 (14)−0.0269 (14)0.0004 (12)−0.0071 (12)
C20.0426 (18)0.0551 (19)0.0351 (16)−0.0264 (15)0.0010 (13)−0.0159 (14)
C30.048 (2)0.056 (2)0.0514 (19)−0.0203 (17)0.0012 (15)−0.0194 (16)
C40.058 (2)0.073 (3)0.079 (3)−0.012 (2)−0.004 (2)−0.036 (2)
C50.049 (2)0.108 (4)0.079 (3)−0.021 (2)0.009 (2)−0.057 (3)
C60.047 (2)0.119 (4)0.047 (2)−0.040 (2)0.0134 (17)−0.038 (2)
C70.0468 (19)0.089 (3)0.0349 (17)−0.0403 (19)0.0018 (14)−0.0203 (17)
C80.065 (2)0.090 (3)0.0297 (17)−0.049 (2)0.0024 (16)−0.0047 (18)
C90.074 (3)0.065 (2)0.0363 (17)−0.044 (2)−0.0098 (17)0.0023 (16)
C100.124 (4)0.070 (3)0.050 (2)−0.049 (3)−0.018 (2)0.016 (2)
C110.156 (5)0.054 (3)0.061 (3)−0.030 (3)−0.026 (3)0.016 (2)
C120.101 (3)0.050 (2)0.076 (3)−0.008 (2)−0.019 (2)−0.009 (2)
C130.069 (2)0.0462 (19)0.0451 (19)−0.0187 (18)−0.0118 (17)−0.0038 (15)
C140.0523 (19)0.0446 (17)0.0352 (16)−0.0268 (15)−0.0055 (14)−0.0043 (13)
C150.0364 (16)0.0331 (14)0.0342 (15)−0.0187 (12)0.0007 (12)−0.0065 (11)
C160.0360 (15)0.0274 (13)0.0345 (15)−0.0171 (12)−0.0003 (11)−0.0066 (11)
C170.0398 (17)0.0420 (16)0.0412 (16)−0.0219 (14)−0.0027 (13)−0.0052 (13)
C180.054 (2)0.0340 (16)0.0535 (19)−0.0187 (14)0.0031 (15)−0.0123 (13)
C190.062 (2)0.0461 (17)0.0374 (16)−0.0354 (17)−0.0100 (15)0.0011 (13)
C200.0317 (15)0.0346 (14)0.0327 (15)−0.0129 (12)0.0002 (12)−0.0087 (12)
C210.0422 (17)0.0358 (15)0.0265 (14)−0.0207 (13)0.0045 (11)−0.0049 (11)
C220.0423 (18)0.0411 (16)0.0498 (18)−0.0197 (14)0.0098 (14)−0.0162 (14)
C230.0414 (18)0.058 (2)0.061 (2)−0.0303 (16)0.0103 (15)−0.0203 (16)
C240.061 (2)0.0409 (17)0.0423 (17)−0.0348 (16)0.0083 (14)−0.0084 (13)
C250.054 (2)0.0329 (15)0.0429 (17)−0.0188 (14)0.0001 (14)−0.0040 (13)
C260.0395 (17)0.0380 (16)0.0430 (17)−0.0178 (14)0.0032 (13)−0.0082 (13)
N10.0426 (14)0.0311 (12)0.0362 (12)−0.0203 (11)−0.0023 (10)−0.0079 (10)
N20.075 (2)0.0366 (14)0.0513 (16)−0.0297 (15)−0.0045 (14)−0.0068 (12)
N30.088 (3)0.070 (2)0.063 (2)−0.061 (2)−0.0171 (19)0.0032 (16)
O10.133 (3)0.089 (2)0.121 (3)−0.087 (2)−0.009 (2)−0.0254 (19)
O20.074 (2)0.101 (2)0.121 (3)−0.063 (2)−0.002 (2)−0.007 (2)
O30.0553 (14)0.0526 (13)0.0437 (12)−0.0285 (11)0.0144 (10)−0.0226 (10)

Geometric parameters (Å, °)

Br1—C241.899 (3)C15—C161.329 (4)
C1—C21.405 (4)C15—H150.9300
C1—C141.410 (4)C16—N11.434 (3)
C1—C151.471 (4)C16—C201.487 (4)
C2—C31.419 (5)C17—C191.353 (4)
C2—C71.436 (4)C17—N11.359 (4)
C3—C41.349 (5)C17—H170.9300
C3—H30.9300C18—N21.305 (4)
C4—C51.408 (6)C18—N11.365 (4)
C4—H40.9300C18—H180.9300
C5—C61.341 (6)C19—N21.351 (4)
C5—H50.9300C19—N31.442 (4)
C6—C71.432 (5)C20—O31.211 (3)
C6—H60.9300C20—C211.497 (4)
C7—C81.379 (5)C21—C261.382 (4)
C8—C91.379 (5)C21—C221.387 (4)
C8—H80.9300C22—C231.387 (4)
C9—C101.417 (5)C22—H220.9300
C9—C141.444 (5)C23—C241.365 (5)
C10—C111.338 (7)C23—H230.9300
C10—H100.9300C24—C251.380 (5)
C11—C121.426 (7)C25—C261.384 (4)
C11—H110.9300C25—H250.9300
C12—C131.358 (5)C26—H260.9300
C12—H120.9300N3—O11.222 (4)
C13—C141.415 (5)N3—O21.224 (5)
C13—H130.9300
C2—C1—C14121.2 (3)C16—C15—H15115.2
C2—C1—C15118.2 (3)C1—C15—H15115.2
C14—C1—C15120.3 (3)C15—C16—N1121.6 (2)
C1—C2—C3123.1 (3)C15—C16—C20122.8 (2)
C1—C2—C7119.1 (3)N1—C16—C20115.5 (2)
C3—C2—C7117.7 (3)C19—C17—N1104.3 (3)
C4—C3—C2121.8 (4)C19—C17—H17127.8
C4—C3—H3119.1N1—C17—H17127.8
C2—C3—H3119.1N2—C18—N1112.3 (3)
C3—C4—C5120.4 (4)N2—C18—H18123.9
C3—C4—H4119.8N1—C18—H18123.9
C5—C4—H4119.8N2—C19—C17112.9 (3)
C6—C5—C4120.6 (4)N2—C19—N3121.2 (3)
C6—C5—H5119.7C17—C19—N3125.9 (4)
C4—C5—H5119.7O3—C20—C16120.7 (2)
C5—C6—C7121.2 (4)O3—C20—C21121.2 (2)
C5—C6—H6119.4C16—C20—C21118.0 (2)
C7—C6—H6119.4C26—C21—C22119.1 (3)
C8—C7—C2119.4 (3)C26—C21—C20124.6 (3)
C8—C7—C6122.3 (3)C22—C21—C20116.3 (3)
C2—C7—C6118.3 (3)C23—C22—C21120.5 (3)
C9—C8—C7122.1 (3)C23—C22—H22119.8
C9—C8—H8118.9C21—C22—H22119.8
C7—C8—H8118.9C24—C23—C22119.0 (3)
C8—C9—C10121.4 (4)C24—C23—H23120.5
C8—C9—C14120.0 (3)C22—C23—H23120.5
C10—C9—C14118.6 (4)C23—C24—C25122.0 (3)
C11—C10—C9121.5 (4)C23—C24—Br1117.4 (2)
C11—C10—H10119.2C25—C24—Br1120.6 (2)
C9—C10—H10119.2C26—C25—C24118.4 (3)
C10—C11—C12120.2 (4)C26—C25—H25120.8
C10—C11—H11119.9C24—C25—H25120.8
C12—C11—H11119.9C21—C26—C25121.0 (3)
C13—C12—C11120.4 (4)C21—C26—H26119.5
C13—C12—H12119.8C25—C26—H26119.5
C11—C12—H12119.8C17—N1—C18106.8 (2)
C12—C13—C14121.0 (4)C17—N1—C16125.3 (2)
C12—C13—H13119.5C18—N1—C16128.0 (2)
C14—C13—H13119.5C18—N2—C19103.7 (3)
C1—C14—C13123.7 (3)O1—N3—O2124.9 (4)
C1—C14—C9118.1 (3)O1—N3—C19117.7 (4)
C13—C14—C9118.1 (3)O2—N3—C19117.4 (3)
C16—C15—C1129.6 (2)
C14—C1—C2—C3−179.0 (3)C1—C15—C16—C20−170.6 (3)
C15—C1—C2—C36.7 (4)N1—C17—C19—N21.0 (3)
C14—C1—C2—C7−0.3 (4)N1—C17—C19—N3−178.9 (3)
C15—C1—C2—C7−174.6 (2)C15—C16—C20—O3168.5 (3)
C1—C2—C3—C4−178.6 (3)N1—C16—C20—O3−8.1 (4)
C7—C2—C3—C42.6 (5)C15—C16—C20—C21−7.7 (4)
C2—C3—C4—C5−0.7 (5)N1—C16—C20—C21175.6 (2)
C3—C4—C5—C6−1.4 (6)O3—C20—C21—C26118.6 (3)
C4—C5—C6—C71.5 (6)C16—C20—C21—C26−65.2 (4)
C1—C2—C7—C8−1.2 (4)O3—C20—C21—C22−59.7 (4)
C3—C2—C7—C8177.6 (3)C16—C20—C21—C22116.5 (3)
C1—C2—C7—C6178.7 (3)C26—C21—C22—C231.7 (4)
C3—C2—C7—C6−2.5 (4)C20—C21—C22—C23−180.0 (3)
C5—C6—C7—C8−179.5 (3)C21—C22—C23—C24−1.0 (5)
C5—C6—C7—C20.5 (5)C22—C23—C24—C25−0.4 (5)
C2—C7—C8—C91.9 (5)C22—C23—C24—Br1178.3 (2)
C6—C7—C8—C9−178.0 (3)C23—C24—C25—C261.2 (5)
C7—C8—C9—C10177.8 (3)Br1—C24—C25—C26−177.4 (2)
C7—C8—C9—C14−1.1 (5)C22—C21—C26—C25−0.9 (4)
C8—C9—C10—C11−177.3 (4)C20—C21—C26—C25−179.1 (3)
C14—C9—C10—C111.7 (6)C24—C25—C26—C21−0.5 (4)
C9—C10—C11—C120.9 (7)C19—C17—N1—C18−0.3 (3)
C10—C11—C12—C13−1.6 (7)C19—C17—N1—C16−178.5 (2)
C11—C12—C13—C14−0.4 (6)N2—C18—N1—C17−0.5 (3)
C2—C1—C14—C13−174.5 (3)N2—C18—N1—C16177.6 (3)
C15—C1—C14—C13−0.3 (4)C15—C16—N1—C1753.4 (4)
C2—C1—C14—C91.1 (4)C20—C16—N1—C17−129.9 (3)
C15—C1—C14—C9175.3 (3)C15—C16—N1—C18−124.4 (3)
C12—C13—C14—C1178.5 (3)C20—C16—N1—C1852.4 (4)
C12—C13—C14—C93.0 (5)N1—C18—N2—C191.0 (3)
C8—C9—C14—C1−0.4 (4)C17—C19—N2—C18−1.3 (4)
C10—C9—C14—C1−179.4 (3)N3—C19—N2—C18178.6 (3)
C8—C9—C14—C13175.4 (3)N2—C19—N3—O10.2 (5)
C10—C9—C14—C13−3.6 (5)C17—C19—N3—O1−180.0 (3)
C2—C1—C15—C16−126.2 (3)N2—C19—N3—O2179.8 (3)
C14—C1—C15—C1659.4 (4)C17—C19—N3—O2−0.3 (5)
C1—C15—C16—N15.8 (5)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C23—H23···O3i0.932.563.303 (4)137

Symmetry codes: (i) −x+2, −y+1, −z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: LH2825).

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