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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 5| May 2012| Page o1413
doi:10.1107/S1600536812015589

4-[(1E)-3-(2,6-Di­chloro-3-fluoro­phen­yl)-3-oxoprop-1-en-1-yl]benzo­nitrile

Aletti S. Praveen,a Hemmige S. Yathirajan,a Badiadka Narayana,b Thomas Gerber,c Eric Hostenc and Richard Betzc*

aUniversity of Mysore, Department of Studies in Chemistry, Manasagangotri, Mysore 570 006, India, bMangalore University, Department of Studies in Chemistry, Mangalagangotri 574 199, India, and cNelson Mandela Metropolitan University, Summerstrand Campus, Department of Chemistry, University Way, Summerstrand, PO Box 77000, Port Elizabeth 6031, South Africa
*Correspondence e-mail: richard.betz@webmail.co.za

(Received 4 April 2012; accepted 10 April 2012; online 18 April 2012)

In the title mol­ecule, C16H8Cl2FNO, the benzene rings form a dihedral angle of 78.69 (8)°. The F atom is disordered over two positions in a 0.530 (3):0.470 (3) ratio. The crystal packing exhibits π–π inter­actions between dichloro-substituted rings [centroid–centroid distance = 3.6671 (10) Å] and weak inter­molecular C—H⋯F contacts.

Related literature

For the biological activity of chalcones, see: Rajendra Prasad et al. (2008[Rajendra Prasad, Y., Praveen Kumar, P., Ravi Kumar, P. & Srinivas Rao, A. (2008). E-J. Chem. 5, 144-148.]); Shivakumar et al. (2005[Shivakumar, P. M., Geetha Babu, S. M. & Mukesh, D. (2005). Chem. Pharm. Bull. 55, 44-49.]); Churkin et al. (1982[Churkin, Yu. D., Panfilova, L. V., Boreko, E. I., Timofeeva, M. M. & Votyakov, V. I. (1982). Pharm. Chem. J. 16, 103-105.]); Herencia et al. (1998[Herencia, F., Ferrandiz, M. L., Ubeda, A., Dominguez, J., Charris, J. E., Lobo, G. M. & Alcaraz, M. J. (1998). Bioorg. Med. Chem. Lett. 8, 1169-1174.]). For a related structure, see: Betz et al. (2012[Betz, R., Gerber, T., Hosten, E., Praveen, A. S., Yathirajan, H. S. & Narayana, B. (2012). Acta Cryst. E68, o512.]). For the graph-set analysis of hydrogen bonds, see: Etter et al. (1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]); Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data

  • C16H8Cl2FNO

  • Mr = 320.13

  • Monoclinic, P 21 /c

  • a = 13.2751 (3) Å

  • b = 8.5002 (2) Å

  • c = 13.9854 (3) Å

  • β = 116.773 (1)°

  • V = 1408.95 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.47 mm−1

  • T = 200 K

  • 0.55 × 0.32 × 0.20 mm
Data collection

  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). SADABS. Bruker Inc., Madison, Wisconsin, USA.]) Tmin = 0.783, Tmax = 0.913

  • 12885 measured reflections

  • 3480 independent reflections

  • 2904 reflections with I > 2σ(I)

  • Rint = 0.013
Refinement

  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.098

  • S = 1.05

  • 3480 reflections

  • 200 parameters

  • H-atom parameters constrained

  • Δρmax = 0.41 e Å−3

  • Δρmin = −0.43 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C1—H1⋯F1Ai 0.95 2.50 3.130 (2) 124
Symmetry code: (i) [-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2010[Bruker (2010). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2010[Bruker (2010). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812015589/cv5282sup1.cif

Supporting information file. DOI: 10.1107/S1600536812015589/cv5282Isup2.cdx

Structure factors: contains datablock I. DOI: 10.1107/S1600536812015589/cv5282Isup3.hkl

Supporting information file. DOI: 10.1107/S1600536812015589/cv5282Isup4.cml

checkCIF report


Comment top

Chalcones are the products of condensation reactions of aromatic aldehydes with acetophenones in the presence of alkali. Chalcones constitute an important group of natural products, and some of them possess a wide range of biological activities such as antimicrobial (Rajendra Prasad et al., 2008), antitubercular (Shivakumar et al., 2005), antiviral (Churkin et al., 1982) and anti-inflammatory activity (Herencia et al., 1998). The crystal structures of some chalcones such as have been reported in the literature. As a part of our ongoing studies on chalcones, the title compound (I) has been synthesized and characterized by X-ray diffraction.

In (I) (Fig. 1), all bond lengths and angles are normal and correspond to those observed in (2E)-1-(2,6-dichloro-3-fluorophenyl)-3-(4-fluorophenyl)prop-2-en-1-one (Betz et al., 2012). The fluorine atom is disordered over two positions with site occupancy factors of 0.530 (3) and 0.470 (3), respectively. The mean planes of the two aromatic rings for a dihedral angle of 78.69 (8)°.

In the crystal, C–H···F contacts (Table 1) whose range falls by more than 0.1 Å below the sum of van-der-Waals radii of the respective atoms are present. These are supported by one of the vinylic hydrogen atoms as well as the disordered fluorine atom. In terms of graph-set analysis (Etter et al., 1990; Bernstein et al., 1995), the descriptor for these hydrogen bonds is C11(8) on the unary level. The shortest intercentroid distance between two aromatic systems was found at 3.6674 (10) Å and is apparent between the halogenated phenyl rings. The packing of the title compound in the crystal structure is shown in Figure 2.

Related literature top

For the biological activity of chalcones, see: Rajendra Prasad et al. (2008); Shivakumar et al. (2005); Churkin et al. (1982); Herencia et al. (1998). For a related structure, see: Betz et al. (2012). For the graph-set analysis of hydrogen bonds, see: Etter et al. (1990); Bernstein et al. (1995).

Experimental top

To a stirred solution of 1-(2,6-dichloro-3-fluorophenyl)ethanone (1 g, 4.8 mmol) and 4-formylbenzonitrile (0.62 g, 4.8 mmol) in ethanol (10 ml), powdered KOH (0.40 g, 7.2 mmol) was added at 273 K. The reaction mixture was stirred at room temperature for 2 h. After completion of the reaction, the mixture was poured into ice cold water and subsequently acidified with 1.5 N HCl (pH ~3). The precipitated solid was filtered and dried to afford 1 g of the title compound as pale yellow solid in 91% yield. The single-crystal was grown from a mixture of toluene:acetone (v:v = 1:1) by slow evaporation at room temperature (m.p.: 414–417 K).

Refinement top

C-bound H atoms were placed in calculated positions (C—H 0.95 Å) and were included in the refinement in the riding model approximation, with U(H) set to 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2010); cell refinement: SAINT (Bruker, 2010); data reduction: SAINT (Bruker, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound showing the atomic numbering and 50% probability displacement ellipsoids. Only the major part of the disordered fluorine atom is shown.
[Figure 2] Fig. 2. A portion of the crystal packing viewed along [010].
4-[(1E)-3-(2,6-Dichloro-3-fluorophenyl)-3-oxoprop-1-en-1-yl]benzonitrile top
Crystal data top
C16H8Cl2FNOF(000) = 648
Mr = 320.13Dx = 1.509 Mg m−3
Monoclinic, P21/cMelting point = 414–417 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 13.2751 (3) ÅCell parameters from 7660 reflections
b = 8.5002 (2) Åθ = 2.9–28.3°
c = 13.9854 (3) ŵ = 0.47 mm−1
β = 116.773 (1)°T = 200 K
V = 1408.95 (6) Å3Platelet, green
Z = 40.55 × 0.32 × 0.20 mm
Data collection top
Bruker APEXII CCD
diffractometer		3480 independent reflections
Radiation source: fine-focus sealed tube2904 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.013
ϕ and ω scansθmax = 28.3°, θmin = 2.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)		h = −17→17
Tmin = 0.783, Tmax = 0.913k = −8→11
12885 measured reflectionsl = −18→18
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.098H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0358P)2 + 0.6287P]
where P = (Fo2 + 2Fc2)/3
3480 reflections(Δ/σ)max < 0.001
200 parametersΔρmax = 0.41 e Å−3
0 restraintsΔρmin = −0.43 e Å−3
Crystal data top
C16H8Cl2FNOV = 1408.95 (6) Å3
Mr = 320.13Z = 4
Monoclinic, P21/cMo Kα radiation
a = 13.2751 (3) ŵ = 0.47 mm−1
b = 8.5002 (2) ÅT = 200 K
c = 13.9854 (3) Å0.55 × 0.32 × 0.20 mm
β = 116.773 (1)°
Data collection top
Bruker APEXII CCD
diffractometer		3480 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)		2904 reflections with I > 2σ(I)
Tmin = 0.783, Tmax = 0.913Rint = 0.013
12885 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0370 restraints
wR(F2) = 0.098H-atom parameters constrained
S = 1.05Δρmax = 0.41 e Å−3
3480 reflectionsΔρmin = −0.43 e Å−3
200 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Cl10.32198 (4)0.25664 (5)0.03764 (4)0.05826 (14)
Cl20.43426 (5)0.87196 (6)0.08058 (4)0.06998 (17)
O10.23229 (11)0.62352 (16)−0.09939 (9)0.0582 (3)
N1−0.11644 (13)0.5937 (3)0.40221 (14)0.0785 (6)
C10.21695 (12)0.57997 (17)0.14653 (12)0.0392 (3)
H10.29270.54730.18910.047*
C20.18838 (14)0.6169 (2)0.04481 (13)0.0460 (4)
H20.11400.65440.00170.055*
C30.26474 (14)0.60326 (19)−0.00432 (12)0.0435 (3)
C4−0.06074 (13)0.5902 (2)0.35969 (14)0.0525 (4)
C110.14352 (12)0.58457 (17)0.19935 (11)0.0370 (3)
C120.03215 (13)0.6397 (2)0.14813 (13)0.0487 (4)
H120.00220.67710.07650.058*
C13−0.03410 (13)0.6403 (2)0.20037 (13)0.0489 (4)
H13−0.10970.67710.16470.059*
C140.00933 (12)0.58722 (18)0.30543 (12)0.0408 (3)
C150.11978 (12)0.5340 (2)0.35809 (12)0.0440 (3)
H150.14980.49840.43010.053*
C160.18571 (12)0.53320 (19)0.30467 (12)0.0407 (3)
H160.26140.49680.34070.049*
C210.38739 (13)0.56076 (18)0.06658 (11)0.0394 (3)
C220.42114 (12)0.40474 (19)0.08897 (11)0.0404 (3)
C240.61343 (14)0.4808 (3)0.19589 (13)0.0538 (4)
H240.68990.45390.24090.065*
C260.47029 (15)0.6754 (2)0.10883 (13)0.0467 (4)
C230.53293 (14)0.3657 (2)0.15222 (13)0.0474 (4)
H230.55420.25820.16560.057*0.470 (3)
F1B0.6550 (2)0.7502 (4)0.2076 (2)0.0847 (11)0.470 (3)
C250.58158 (15)0.6354 (2)0.17347 (14)0.0545 (4)
H250.63670.71600.20270.065*0.530 (3)
F1A0.56085 (16)0.2148 (3)0.16948 (16)0.0610 (7)0.530 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0520 (2)0.0417 (2)0.0616 (3)−0.00337 (17)0.00832 (19)0.00136 (18)
Cl20.1033 (4)0.0436 (2)0.0648 (3)−0.0126 (2)0.0394 (3)−0.0003 (2)
O10.0635 (7)0.0718 (9)0.0403 (6)0.0168 (6)0.0242 (6)0.0145 (6)
N10.0455 (8)0.1321 (18)0.0629 (10)0.0129 (10)0.0288 (8)−0.0008 (11)
C10.0376 (7)0.0386 (7)0.0407 (7)0.0002 (6)0.0171 (6)0.0005 (6)
C20.0444 (8)0.0502 (9)0.0432 (8)0.0089 (7)0.0195 (7)0.0076 (7)
C30.0508 (8)0.0405 (8)0.0406 (8)0.0047 (7)0.0217 (7)0.0052 (6)
C40.0361 (7)0.0725 (12)0.0473 (9)0.0051 (8)0.0172 (7)−0.0027 (8)
C110.0355 (7)0.0349 (7)0.0389 (7)−0.0007 (6)0.0153 (6)−0.0010 (6)
C120.0397 (8)0.0596 (10)0.0418 (8)0.0076 (7)0.0139 (6)0.0099 (7)
C130.0336 (7)0.0586 (10)0.0497 (9)0.0088 (7)0.0146 (6)0.0058 (7)
C140.0346 (7)0.0428 (8)0.0451 (8)−0.0006 (6)0.0182 (6)−0.0052 (6)
C150.0392 (7)0.0525 (9)0.0404 (7)0.0054 (6)0.0179 (6)0.0025 (7)
C160.0332 (7)0.0465 (8)0.0401 (7)0.0059 (6)0.0147 (6)0.0024 (6)
C210.0461 (8)0.0440 (8)0.0327 (7)0.0000 (6)0.0219 (6)0.0015 (6)
C220.0405 (7)0.0443 (8)0.0348 (7)−0.0011 (6)0.0155 (6)−0.0012 (6)
C240.0390 (8)0.0831 (13)0.0393 (8)−0.0030 (8)0.0176 (7)−0.0014 (8)
C260.0603 (9)0.0472 (9)0.0411 (8)−0.0065 (7)0.0303 (7)−0.0005 (7)
C230.0464 (8)0.0571 (10)0.0389 (7)0.0080 (7)0.0193 (7)0.0015 (7)
F1B0.0738 (17)0.107 (2)0.0622 (16)−0.0519 (16)0.0211 (13)−0.0060 (14)
C250.0535 (9)0.0717 (12)0.0433 (8)−0.0211 (9)0.0260 (8)−0.0071 (8)
F1A0.0529 (11)0.0588 (13)0.0594 (12)0.0184 (9)0.0147 (9)0.0096 (9)
Geometric parameters (Å, º) top
Cl1—C221.7267 (16)C13—H130.9500
Cl2—C261.7338 (18)C14—C151.387 (2)
O1—C31.2112 (18)C15—C161.383 (2)
N1—C41.139 (2)C15—H150.9500
C1—C21.334 (2)C16—H160.9500
C1—C111.465 (2)C21—C261.387 (2)
C1—H10.9500C21—C221.390 (2)
C2—C31.463 (2)C22—C231.383 (2)
C2—H20.9500C24—C231.373 (3)
C3—C211.520 (2)C24—C251.373 (3)
C4—C141.441 (2)C24—H240.9500
C11—C161.390 (2)C26—C251.383 (3)
C11—C121.402 (2)C23—F1A1.327 (3)
C12—C131.373 (2)C23—H230.9500
C12—H120.9500F1B—C251.308 (3)
C13—C141.390 (2)C25—H250.9500
C2—C1—C11126.67 (14)C15—C16—H16119.3
C2—C1—H1116.7C11—C16—H16119.3
C11—C1—H1116.7C26—C21—C22117.46 (14)
C1—C2—C3123.90 (14)C26—C21—C3121.47 (15)
C1—C2—H2118.1C22—C21—C3121.05 (14)
C3—C2—H2118.1C23—C22—C21121.15 (15)
O1—C3—C2121.68 (15)C23—C22—Cl1119.24 (13)
O1—C3—C21119.79 (14)C21—C22—Cl1119.61 (11)
C2—C3—C21118.53 (13)C23—C24—C25118.87 (16)
N1—C4—C14179.4 (2)C23—C24—H24120.6
C16—C11—C12118.39 (14)C25—C24—H24120.6
C16—C11—C1118.96 (13)C25—C26—C21120.98 (17)
C12—C11—C1122.65 (13)C25—C26—Cl2119.32 (14)
C13—C12—C11120.68 (15)C21—C26—Cl2119.70 (13)
C13—C12—H12119.7F1A—C23—C24120.69 (17)
C11—C12—H12119.7F1A—C23—C22118.67 (17)
C12—C13—C14120.06 (14)C24—C23—C22120.64 (17)
C12—C13—H13120.0F1A—C23—H231.0
C14—C13—H13120.0C24—C23—H23119.7
C15—C14—C13120.21 (14)C22—C23—H23119.7
C15—C14—C4120.30 (14)F1B—C25—C24121.9 (2)
C13—C14—C4119.48 (14)F1B—C25—C26117.1 (2)
C16—C15—C14119.30 (14)C24—C25—C26120.87 (16)
C16—C15—H15120.4F1B—C25—H253.7
C14—C15—H15120.4C24—C25—H25119.6
C15—C16—C11121.34 (13)C26—C25—H25119.6
C11—C1—C2—C3−177.25 (15)C26—C21—C22—C230.9 (2)
C1—C2—C3—O1172.76 (17)C3—C21—C22—C23179.07 (13)
C1—C2—C3—C21−6.6 (2)C26—C21—C22—Cl1−179.43 (11)
C2—C1—C11—C16176.31 (16)C3—C21—C22—Cl1−1.24 (19)
C2—C1—C11—C12−4.1 (3)C22—C21—C26—C25−2.0 (2)
C16—C11—C12—C13−1.1 (2)C3—C21—C26—C25179.84 (14)
C1—C11—C12—C13179.29 (16)C22—C21—C26—Cl2178.12 (11)
C11—C12—C13—C140.6 (3)C3—C21—C26—Cl2−0.07 (19)
C12—C13—C14—C150.2 (3)C25—C24—C23—F1A178.08 (18)
C12—C13—C14—C4179.32 (17)C25—C24—C23—C22−1.7 (2)
N1—C4—C14—C15136 (21)C21—C22—C23—F1A−178.81 (16)
N1—C4—C14—C13−43 (21)Cl1—C22—C23—F1A1.5 (2)
C13—C14—C15—C16−0.5 (2)C21—C22—C23—C240.9 (2)
C4—C14—C15—C16−179.57 (16)Cl1—C22—C23—C24−178.75 (12)
C14—C15—C16—C110.0 (2)C23—C24—C25—F1B−176.2 (2)
C12—C11—C16—C150.8 (2)C23—C24—C25—C260.6 (2)
C1—C11—C16—C15−179.54 (14)C21—C26—C25—F1B178.18 (19)
O1—C3—C21—C2684.6 (2)Cl2—C26—C25—F1B−1.9 (2)
C2—C3—C21—C26−96.08 (18)C21—C26—C25—C241.3 (2)
O1—C3—C21—C22−93.55 (19)Cl2—C26—C25—C24−178.81 (13)
C2—C3—C21—C2285.81 (19)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···F1Ai0.952.503.130 (2)124
Symmetry code: (i) −x+1, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formulaC16H8Cl2FNO
Mr320.13
Crystal system, space groupMonoclinic, P21/c
Temperature (K)200
a, b, c (Å)13.2751 (3), 8.5002 (2), 13.9854 (3)
β (°) 116.773 (1)
V (Å3)1408.95 (6)
Z4
Radiation typeMo Kα
µ (mm−1)0.47
Crystal size (mm)0.55 × 0.32 × 0.20
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.783, 0.913
No. of measured, independent and
observed [I > 2σ(I)] reflections		12885, 3480, 2904
Rint0.013
(sin θ/λ)max (Å−1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.098, 1.05
No. of reflections3480
No. of parameters200
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.41, −0.43

Computer programs: APEX2 (Bruker, 2010), SAINT (Bruker, 2010), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2008), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···F1Ai0.952.503.130 (2)123.7
Symmetry code: (i) −x+1, y+1/2, −z+1/2.
 

Acknowledgements

ASP thanks the University of Mysore for the research facilities.

References

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ISSN: 2056-9890
Volume 68| Part 5| May 2012| Page o1413
doi:10.1107/S1600536812015589
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