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

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ISSN: 2056-9890

(2E)-1-(2,6-Di­chloro-3-fluoro­phen­yl)-3-(4-fluoro­phen­yl)prop-2-en-1-one

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

(Received 13 January 2012; accepted 20 January 2012; online 25 January 2012)

In the title compound, C15H8Cl2F2O, the C=C double bond is in the E configuration. In the cyrstal, C—H⋯O hydrogen bonds connect the mol­ecules into chains along the c axis. A ππ inter­action of 3.628 (1) Å is also observed between two polyhalogenated benzene rings. The dichloro­substituted ring exhibits partial disorder over two sets of sites, with site-occupancy factors of 0.573 (3) and 0.427 (3).

Related literature

For pharmaceutical background to chalcones, see: Nielsen et al. (2004[Nielsen, S. F., Boesen, T., Larsen, M., Schonning, K. & Kromann, H. (2004). Bioorg. Med. Chem. 12, 3047-3054.]); Modzelewska et al. (2006[Modzelewska, A., Pettit, C., Achanta, G., Davidson, N. E., Huang, P. & Khan, S. R. (2006). Bioorg. Med. Chem. 14, 3491-3495.]); Nowakowska (2007[Nowakowska, Z. (2007). Eur. J. Med. Chem. 42, 125-137.]); Ni et al. (2004[Ni, L., Meng, C. Q. & Sikorski, J. A. (2004). Expert Opin. Ther. Pat. 14, 1669-1691.]). For related structures, see: Yathirajan et al. (2006[Yathirajan, H. S., Sarojini, B. K., Narayana, B., Bindya, S. & Bolte, M. (2006). Acta Cryst. E62, o3631-o3632.], 2007[Yathirajan, H. S., Mayekar, A. N., Sarojini, B. K., Narayana, B. & Bolte, M. (2007). Acta Cryst. E63, o426-o427.]); Betz et al. (2011[Betz, R., Gerber, T., Hosten, E., Samshuddin, S., Narayana, B. & Yathirajan, H. S. (2011). Acta Cryst. E67, o3181-o3182.]). For 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
  • C15H8Cl2F2O

  • Mr = 313.11

  • Monoclinic, P 21 /c

  • a = 12.2311 (3) Å

  • b = 10.3115 (2) Å

  • c = 11.2468 (3) Å

  • β = 108.935 (1)°

  • V = 1341.70 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.50 mm−1

  • T = 200 K

  • 0.48 × 0.34 × 0.27 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.825, Tmax = 1.000

  • 12634 measured reflections

  • 3328 independent reflections

  • 2724 reflections with I > 2σ(I)

  • Rint = 0.015

Refinement
  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 0.092

  • S = 1.06

  • 3328 reflections

  • 191 parameters

  • H-atom parameters constrained

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.25 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C1—H1⋯O1i 0.95 2.51 3.3982 (16) 156
C12—H12⋯O1i 0.95 2.55 3.4266 (19) 153
Symmetry code: (i) [x, -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


Comment top

Chalcones constitute an important group of natural products and some of them possess a wide range of biological activities, such as antibacterial (Nielsen et al., 2004) and anticancer (Modzelewska et al., 2006). A review of anti-infective and anti-inflammatory chalcones (Nowakowska, 2007) and recent advances in therapeutic chalcones have been reported (Ni et al., 2004). Related crystal structures of some chalcones, e.g. 1-(2,4-dichloro-5- fluorophenyl)-3-(3,4-dimethoxyphenyl)prop-2-en-1-one (Yathirajan et al., 2006) and (2E)-1-(2,4-dichlorophenyl)-3-(2-hydroxyphenyl)prop-2-en-1-one (Yathirajan et al., 2007) have been reported. As part of our ongoing studies on chalcones (Betz et al., 2011), the title compound was synthesized and its crystal structure is reported here.

The CC double bond of the Michael system is in the E configuration. The fluorine atom on the polyhalogenated phenyl ring, together with its attached carbon atom is disordered over two sites, as are the ring CH meta to it. The site occupancy factors refined to 0.573 (3) and 0.427 (3). The least-squares planes defined by the carbon atoms of the two rings make a dihedral angle of 82.37 (8)° (Fig. 1).

In the crystal structure, intermolecular C—H···O hydrogen bonds are observed (Table 1 and Fig. 2), forming a 6-membered chelate ring. In terms of graph-set analysis (Etter et al., 1990; Bernstein et al., 1995), the descriptor for this pattern is C11(5)C11(7) on the unitary level. Molecules are connected into chains along the crystallographic c axis. A ππ interaction of 3.628 (1) Å is also observed between two polyhalogenated phenyl rings. The packing of the title compound in the crystal structure is shown in Fig. 3.

Related literature top

For pharmaceutical background to chalcones, see: Nielsen et al. (2004); Modzelewska et al. (2006); Nowakowska (2007); Ni et al. (2004). For related structures, see: Yathirajan et al. (2006, 2007); Betz et al. (2011). For 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-fluorobenzaldehyde (0.59 g, 4.8 mmol) in ethanol (10 ml), powdered KOH (0.4 g 7.2 mmol) was added at 273 K. The reaction mixture was stirred at room temperature for 1 h. After completion of the reaction, the reaction mixture was poured into ice cold water and acidified with 1.5 N HCl (pH ~3). The resulting precipitate was filtered and dried to afford 1.3 g of the title compound as a pale yellow solid in 86% yield. Single crystals suitable for the diffraction study were grown from a mixture of toluene:acetone (v:v = 1:1) by slow evaporation at room temperature (m.p.: 421–424 K).

Refinement top

H atoms were placed in calculated positions (C—H = 0.95 Å) and were included in the refinement in the riding model approximation, with Uiso(H) = 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, with anisotropic displacement ellipsoids drawn at the 50% probability level. For clarity, only the major component of the disorder model is depicted.
[Figure 2] Fig. 2. Intermolecular contacts, viewed along [-1 0 0]. For clarity, only the major component of the disorder model is depicted. Symmetry operators: i x, -y + 1/2, z - 1/2; ii x, -y + 1/2, z + 1/2. Dashed lines indicate hydrogen bonds.
[Figure 3] Fig. 3. Molecular packing of the title compound, viewed along [0 1 0]. Anisotropic displacement ellipsoids are drawn at the 50% probability level. For clarity, only the major component of the disorder model is depicted.
(2E)-1-(2,6-Dichloro-3-fluorophenyl)-3-(4-fluorophenyl)prop-2-en-1-one top
Crystal data top
C15H8Cl2F2OF(000) = 632
Mr = 313.11Dx = 1.550 Mg m3
Monoclinic, P21/cMelting point = 421–424 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 12.2311 (3) ÅCell parameters from 7019 reflections
b = 10.3115 (2) Åθ = 2.7–28.2°
c = 11.2468 (3) ŵ = 0.50 mm1
β = 108.935 (1)°T = 200 K
V = 1341.70 (6) Å3Block, colourless
Z = 40.48 × 0.34 × 0.27 mm
Data collection top
Bruker APEXII CCD
diffractometer
3328 independent reflections
Radiation source: fine-focus sealed tube2724 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.015
ϕ and ω scansθmax = 28.3°, θmin = 2.7°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 1616
Tmin = 0.825, Tmax = 1.000k = 1213
12634 measured reflectionsl = 1314
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)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.092H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.0346P)2 + 0.5003P]
where P = (Fo2 + 2Fc2)/3
3328 reflections(Δ/σ)max < 0.001
191 parametersΔρmax = 0.24 e Å3
0 restraintsΔρmin = 0.25 e Å3
Crystal data top
C15H8Cl2F2OV = 1341.70 (6) Å3
Mr = 313.11Z = 4
Monoclinic, P21/cMo Kα radiation
a = 12.2311 (3) ŵ = 0.50 mm1
b = 10.3115 (2) ÅT = 200 K
c = 11.2468 (3) Å0.48 × 0.34 × 0.27 mm
β = 108.935 (1)°
Data collection top
Bruker APEXII CCD
diffractometer
3328 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
2724 reflections with I > 2σ(I)
Tmin = 0.825, Tmax = 1.000Rint = 0.015
12634 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.092H-atom parameters constrained
S = 1.06Δρmax = 0.24 e Å3
3328 reflectionsΔρmin = 0.25 e Å3
191 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Cl10.55532 (4)0.18042 (5)0.01581 (4)0.05973 (14)
Cl20.18584 (5)0.50107 (5)0.10590 (5)0.06391 (15)
F10.02753 (11)0.32385 (11)0.03660 (13)0.0767 (4)
O10.33883 (11)0.32276 (11)0.25385 (9)0.0498 (3)
C10.23362 (12)0.10980 (13)0.06621 (12)0.0366 (3)
H10.26850.15270.01170.044*
C20.25296 (12)0.16144 (14)0.16699 (12)0.0378 (3)
H20.21980.12040.24620.045*
C30.32232 (13)0.27733 (14)0.16076 (12)0.0380 (3)
C110.16497 (12)0.00496 (13)0.06298 (13)0.0362 (3)
C120.16714 (14)0.05235 (15)0.05394 (14)0.0435 (3)
H120.21290.00950.12820.052*
C130.10377 (16)0.16073 (16)0.06360 (16)0.0522 (4)
H130.10680.19390.14340.063*
C140.03673 (15)0.21884 (16)0.04488 (18)0.0522 (4)
C150.03053 (15)0.17524 (16)0.16235 (17)0.0515 (4)
H150.01730.21770.23580.062*
C160.09524 (14)0.06845 (15)0.17128 (14)0.0449 (3)
H160.09250.03750.25180.054*
C210.37356 (13)0.34472 (13)0.03476 (12)0.0388 (3)
C220.31594 (15)0.44789 (15)0.00230 (14)0.0448 (3)
C240.46503 (18)0.47039 (18)0.19724 (16)0.0586 (5)
H240.49560.51260.27620.070*
C260.47854 (14)0.30709 (15)0.05110 (13)0.0434 (3)
C2310.36195 (18)0.50942 (16)0.11341 (16)0.0545 (5)0.573 (3)
F2310.3031 (2)0.60294 (18)0.14524 (19)0.0723 (7)0.573 (3)
C2510.52385 (16)0.36950 (18)0.16607 (15)0.0541 (5)0.573 (3)
H2510.59590.34230.22350.065*0.573 (3)
C2320.36195 (18)0.50942 (16)0.11341 (16)0.0545 (5)0.427 (3)
H2520.32120.57950.13440.065*0.427 (3)
C2520.52385 (16)0.36950 (18)0.16607 (15)0.0541 (5)0.427 (3)
F2320.6202 (2)0.3318 (3)0.2413 (2)0.0763 (10)0.427 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0634 (3)0.0683 (3)0.0456 (2)0.0139 (2)0.01502 (18)0.00247 (19)
Cl20.0770 (3)0.0586 (3)0.0613 (3)0.0189 (2)0.0295 (2)0.0032 (2)
F10.0894 (8)0.0584 (7)0.0933 (9)0.0277 (6)0.0450 (7)0.0037 (6)
O10.0714 (7)0.0513 (6)0.0305 (5)0.0051 (5)0.0216 (5)0.0038 (4)
C10.0447 (7)0.0352 (7)0.0304 (6)0.0025 (6)0.0129 (5)0.0027 (5)
C20.0467 (7)0.0392 (7)0.0282 (6)0.0018 (6)0.0131 (5)0.0042 (5)
C30.0492 (8)0.0386 (7)0.0281 (6)0.0042 (6)0.0148 (5)0.0012 (5)
C110.0419 (7)0.0353 (7)0.0345 (6)0.0049 (5)0.0165 (6)0.0011 (5)
C120.0533 (8)0.0427 (8)0.0367 (7)0.0006 (7)0.0178 (6)0.0004 (6)
C130.0643 (10)0.0490 (9)0.0503 (9)0.0021 (8)0.0282 (8)0.0066 (7)
C140.0563 (9)0.0412 (8)0.0672 (10)0.0065 (7)0.0313 (8)0.0042 (7)
C150.0550 (9)0.0502 (9)0.0529 (9)0.0085 (7)0.0226 (7)0.0146 (7)
C160.0520 (8)0.0474 (8)0.0379 (7)0.0026 (7)0.0182 (6)0.0062 (6)
C210.0541 (8)0.0370 (7)0.0301 (6)0.0070 (6)0.0202 (6)0.0002 (5)
C220.0640 (9)0.0382 (7)0.0395 (7)0.0061 (7)0.0267 (7)0.0007 (6)
C240.0836 (13)0.0601 (10)0.0386 (8)0.0307 (10)0.0289 (9)0.0147 (7)
C260.0552 (9)0.0471 (8)0.0319 (7)0.0070 (7)0.0198 (6)0.0007 (6)
C2310.0868 (13)0.0428 (8)0.0477 (9)0.0151 (8)0.0407 (9)0.0105 (7)
F2310.1165 (18)0.0509 (11)0.0629 (12)0.0040 (10)0.0478 (12)0.0140 (8)
C2510.0628 (10)0.0656 (11)0.0349 (8)0.0214 (8)0.0175 (7)0.0026 (7)
C2320.0868 (13)0.0428 (8)0.0477 (9)0.0151 (8)0.0407 (9)0.0105 (7)
C2520.0628 (10)0.0656 (11)0.0349 (8)0.0214 (8)0.0175 (7)0.0026 (7)
F2320.0659 (17)0.113 (2)0.0383 (13)0.0239 (16)0.0011 (11)0.0047 (13)
Geometric parameters (Å, º) top
Cl1—C261.7284 (16)C13—H130.9500
Cl2—C221.7284 (18)C14—C151.374 (2)
F1—C141.3588 (18)C15—C161.379 (2)
O1—C31.2220 (16)C15—H150.9500
C1—C21.3410 (19)C16—H160.9500
C1—C111.4582 (19)C21—C261.388 (2)
C1—H10.9500C21—C221.389 (2)
C2—C31.454 (2)C22—C2311.392 (2)
C2—H20.9500C24—C2311.367 (3)
C3—C211.5190 (19)C24—C2511.373 (3)
C11—C121.3950 (19)C24—H240.9500
C11—C161.402 (2)C26—C2511.389 (2)
C12—C131.384 (2)C231—F2311.321 (2)
C12—H120.9500C251—H2510.9500
C13—C141.368 (3)
C2—C1—C11127.18 (13)C16—C15—H15120.7
C2—C1—H1116.4C15—C16—C11120.76 (14)
C11—C1—H1116.4C15—C16—H16119.6
C1—C2—C3123.09 (13)C11—C16—H16119.6
C1—C2—H2118.5C26—C21—C22117.71 (13)
C3—C2—H2118.5C26—C21—C3121.98 (13)
O1—C3—C2121.99 (13)C22—C21—C3120.31 (14)
O1—C3—C21119.41 (13)C21—C22—C231120.61 (16)
C2—C3—C21118.59 (11)C21—C22—Cl2120.04 (12)
C12—C11—C16118.39 (13)C231—C22—Cl2119.35 (13)
C12—C11—C1118.21 (13)C231—C24—C251119.29 (15)
C16—C11—C1123.38 (13)C231—C24—H24120.4
C13—C12—C11121.12 (14)C251—C24—H24120.4
C13—C12—H12119.4C21—C26—C251121.18 (15)
C11—C12—H12119.4C21—C26—Cl1120.02 (11)
C14—C13—C12118.20 (15)C251—C26—Cl1118.79 (14)
C14—C13—H13120.9F231—C231—C24119.34 (17)
C12—C13—H13120.9F231—C231—C22119.7 (2)
F1—C14—C13118.73 (16)C24—C231—C22120.88 (16)
F1—C14—C15118.28 (16)C24—C251—C26120.32 (17)
C13—C14—C15122.98 (15)C24—C251—H251119.8
C14—C15—C16118.52 (15)C26—C251—H251119.8
C14—C15—H15120.7
C11—C1—C2—C3179.51 (13)C2—C3—C21—C2294.75 (16)
C1—C2—C3—O1180.00 (14)C26—C21—C22—C2310.9 (2)
C1—C2—C3—C211.2 (2)C3—C21—C22—C231179.49 (13)
C2—C1—C11—C12172.16 (14)C26—C21—C22—Cl2179.08 (11)
C2—C1—C11—C169.1 (2)C3—C21—C22—Cl20.51 (18)
C16—C11—C12—C131.1 (2)C22—C21—C26—C2510.7 (2)
C1—C11—C12—C13179.87 (14)C3—C21—C26—C251179.74 (13)
C11—C12—C13—C141.4 (2)C22—C21—C26—Cl1179.36 (11)
C12—C13—C14—F1178.78 (15)C3—C21—C26—Cl10.22 (19)
C12—C13—C14—C150.7 (3)C251—C24—C231—F231177.32 (16)
F1—C14—C15—C16179.77 (15)C251—C24—C231—C220.3 (2)
C13—C14—C15—C160.3 (3)C21—C22—C231—F231176.54 (16)
C14—C15—C16—C110.6 (2)Cl2—C22—C231—F2313.5 (2)
C12—C11—C16—C150.1 (2)C21—C22—C231—C240.4 (2)
C1—C11—C16—C15178.78 (14)Cl2—C22—C231—C24179.57 (13)
O1—C3—C21—C2695.46 (17)C231—C24—C251—C260.6 (2)
C2—C3—C21—C2685.68 (17)C21—C26—C251—C240.1 (2)
O1—C3—C21—C2284.11 (18)Cl1—C26—C251—C24179.89 (12)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···O1i0.952.513.3982 (16)156
C12—H12···O1i0.952.553.4266 (19)153
Symmetry code: (i) x, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC15H8Cl2F2O
Mr313.11
Crystal system, space groupMonoclinic, P21/c
Temperature (K)200
a, b, c (Å)12.2311 (3), 10.3115 (2), 11.2468 (3)
β (°) 108.935 (1)
V3)1341.70 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.50
Crystal size (mm)0.48 × 0.34 × 0.27
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.825, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
12634, 3328, 2724
Rint0.015
(sin θ/λ)max1)0.668
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.092, 1.06
No. of reflections3328
No. of parameters191
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.24, 0.25

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···O1i0.952.513.3982 (16)156.2
C12—H12···O1i0.952.553.4266 (19)153.1
Symmetry code: (i) x, y+1/2, z+1/2.
 

Acknowledgements

ASP thanks the University of Mysore for research facilities.

References

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