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-phenyl­prop-2-en-1-one

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 27 February 2012; accepted 9 March 2012; online 17 March 2012)

In the title compound, C15H9Cl2FO, the F atom shows positional disorder over two positions, with site-occupancy factors of 0.747 (4) and 0.253 (4). The dihedral angle between the rings is 86.37 (10)°. In the crystal, C—H⋯O contacts connect the mol­ecules into chains along the c axis. The shortest inter-centroid distance between two aromatic systems is 3.6686 (12) Å and is apparent between the halogenated rings.

Related literature

For pharmaceutical background to chalcones, see: Lin et al. (2002[Lin, Y. M., Zhou, Y., Flavin, M. T., Zhou, L. M., Nie, W. & Chen, F. C. (2002). Bioorg. Med. Chem. 10, 2795-2802.]); 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.]); Svetaz et al. (2004[Svetaz, L., Tapia, A., Lopez, S., Furlan, R. L. E., Petenatti, E., Pioli, R., Schmeda-Hirschmann, G. & Zacchino, S. A. (2004). J. Agric. Food Chem. 52, 3297-3300.]). For related structures, 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 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
  • C15H9Cl2FO

  • Mr = 295.12

  • Monoclinic, P 21 /c

  • a = 11.3390 (3) Å

  • b = 10.3896 (3) Å

  • c = 11.3930 (3) Å

  • β = 97.078 (1)°

  • V = 1331.95 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.49 mm−1

  • T = 200 K

  • 0.49 × 0.34 × 0.17 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). SADABS. Bruker Inc., Madison, Wisconsin, USA.]) Tmin = 0.798, Tmax = 0.920

  • 23002 measured reflections

  • 3329 independent reflections

  • 2742 reflections with I > 2σ(I)

  • Rint = 0.025

Refinement
  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.111

  • S = 1.04

  • 3329 reflections

  • 182 parameters

  • H-atom parameters constrained

  • Δρmax = 0.58 e Å−3

  • Δρmin = −0.60 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 2.50 3.399 (2) 158
C16—H16⋯O1i 0.95 2.57 3.440 (2) 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

Substituted chalcones and their derivatives have been reported to possess interesting biological properties such as being antitubercular (Lin et al., 2002), anticancer (Modzelewska et al., 2006) and antifungal agents (Svetaz et al., 2004). The crystal structures of some chalcones such as (2E)-1-(2,6-Dichloro-3-fluorophenyl)-3-(4-fluorophenyl)prop-2-en-1-one (Betz et al., 2012) have been reported in the literature. As part of our ongoing studies on chalcones, the title compound was synthesized and characterized by X-ray diffraction.

The fluorine atom on the halogenated phenyl ring shows rotational disorder over two positions with site occupancy factors of 0.75 and 0.25. The least-squares planes defined by the carbon atoms of the two aromatic moieties intersect at an angle of 86.37 (10)° (Fig. 1).

In the crystal, C–H···O contacts 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 and one of the hydrogen atoms of the unsubstituted phenyl ring. In terms of graph-set analysis (Etter et al., 1990; Bernstein et al., 1995), the descriptor for the hydrogen bonds is C11(5)C11(7) on the unary level. Metrical information about these contacts as well as their symmetry is summarized in Table 1. In total, the molecules are connected to chains along the crystallographic c axis. The shortest intercentroid distance between two aromtic systems was measured at 3.6686 (12) Å and is apparent between the halogenated phenyl rings (Fig. 2).

The packing of the title compound in the crystal structure is shown in Figure 3.

Related literature top

For pharmaceutical background to chalcones, see: Lin et al. (2002); Modzelewska et al. (2006); Svetaz et al. (2004). For related structures, see: Betz et al. (2012). 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 benzaldehyde (0.51 g, 4.8 mmol) in ethanol (10 ml), powdered KOH (0.40 g 7.2 mmol) was added at 0 °C. The reaction mixture was stirred at room temperature for 2 h. After completion of the reaction, the mixture was pourred into ice cold water and subsequently acidified with 1.5 N HCl (pH ~3). The precipitated solid was filtered and dried to afford 1.2 g of the title compound as off-white solid in 86% yield. The single-crystal was grown from a mixture of toluene:acetone (v:v = 1:1) by slow evaporation at room temperature (m.p.: 385–388 K).

Refinement top

Carbon-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).

Structure description top

Substituted chalcones and their derivatives have been reported to possess interesting biological properties such as being antitubercular (Lin et al., 2002), anticancer (Modzelewska et al., 2006) and antifungal agents (Svetaz et al., 2004). The crystal structures of some chalcones such as (2E)-1-(2,6-Dichloro-3-fluorophenyl)-3-(4-fluorophenyl)prop-2-en-1-one (Betz et al., 2012) have been reported in the literature. As part of our ongoing studies on chalcones, the title compound was synthesized and characterized by X-ray diffraction.

The fluorine atom on the halogenated phenyl ring shows rotational disorder over two positions with site occupancy factors of 0.75 and 0.25. The least-squares planes defined by the carbon atoms of the two aromatic moieties intersect at an angle of 86.37 (10)° (Fig. 1).

In the crystal, C–H···O contacts 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 and one of the hydrogen atoms of the unsubstituted phenyl ring. In terms of graph-set analysis (Etter et al., 1990; Bernstein et al., 1995), the descriptor for the hydrogen bonds is C11(5)C11(7) on the unary level. Metrical information about these contacts as well as their symmetry is summarized in Table 1. In total, the molecules are connected to chains along the crystallographic c axis. The shortest intercentroid distance between two aromtic systems was measured at 3.6686 (12) Å and is apparent between the halogenated phenyl rings (Fig. 2).

The packing of the title compound in the crystal structure is shown in Figure 3.

For pharmaceutical background to chalcones, see: Lin et al. (2002); Modzelewska et al. (2006); Svetaz et al. (2004). For related structures, see: Betz et al. (2012). For graph-set analysis of hydrogen bonds, see: Etter et al. (1990); Bernstein et al. (1995).

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 atom labels and anisotropic displacement ellipsoids (drawn at 50% probability level).
[Figure 2] Fig. 2. Intermolecular contacts, viewed along [1 0 0]. Symmetry operators: i x, -y + 1/2, z + 1/2; ii x, -y + 1/2, z - 1/2.
[Figure 3] Fig. 3. Molecular packing of the title compound, viewed along [0 1 0] (anisotropic displacement ellipsoids drawn at 50% probability level).
(2E)-1-(2,6-Dichloro-3-fluorophenyl)-3-phenylprop-2-en-1-one top
Crystal data top
C15H9Cl2FOF(000) = 600
Mr = 295.12Dx = 1.472 Mg m3
Monoclinic, P21/cMelting point = 385–388 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 11.3390 (3) ÅCell parameters from 9971 reflections
b = 10.3896 (3) Åθ = 2.7–28.3°
c = 11.3930 (3) ŵ = 0.49 mm1
β = 97.078 (1)°T = 200 K
V = 1331.95 (6) Å3Block, colourless
Z = 40.49 × 0.34 × 0.17 mm
Data collection top
Bruker APEXII CCD
diffractometer
3329 independent reflections
Radiation source: fine-focus sealed tube2742 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.025
φ and ω scansθmax = 28.4°, θmin = 2.7°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 1515
Tmin = 0.798, Tmax = 0.920k = 1313
23002 measured reflectionsl = 1515
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)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.111H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.040P)2 + 0.7737P]
where P = (Fo2 + 2Fc2)/3
3329 reflections(Δ/σ)max = 0.001
182 parametersΔρmax = 0.58 e Å3
0 restraintsΔρmin = 0.60 e Å3
Crystal data top
C15H9Cl2FOV = 1331.95 (6) Å3
Mr = 295.12Z = 4
Monoclinic, P21/cMo Kα radiation
a = 11.3390 (3) ŵ = 0.49 mm1
b = 10.3896 (3) ÅT = 200 K
c = 11.3930 (3) Å0.49 × 0.34 × 0.17 mm
β = 97.078 (1)°
Data collection top
Bruker APEXII CCD
diffractometer
3329 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
2742 reflections with I > 2σ(I)
Tmin = 0.798, Tmax = 0.920Rint = 0.025
23002 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.111H-atom parameters constrained
S = 1.04Δρmax = 0.58 e Å3
3329 reflectionsΔρmin = 0.60 e Å3
182 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Cl10.83699 (6)0.03537 (6)0.06241 (5)0.06914 (19)
Cl20.43775 (5)0.32132 (6)0.01452 (5)0.07146 (19)
O10.67486 (13)0.20446 (13)0.16536 (10)0.0526 (3)
C10.76748 (14)0.40662 (15)0.08071 (14)0.0373 (3)
H10.73250.35700.13740.045*
C20.75116 (16)0.36328 (16)0.03056 (14)0.0410 (4)
H20.78320.41140.09010.049*
C30.68640 (16)0.24564 (16)0.06433 (13)0.0399 (3)
C110.83272 (14)0.52106 (15)0.12542 (14)0.0373 (3)
C120.89663 (17)0.59959 (17)0.05617 (17)0.0486 (4)
H120.89860.57980.02500.058*
C130.95691 (18)0.70569 (19)0.1055 (2)0.0569 (5)
H131.00180.75740.05840.068*
C140.9526 (2)0.7373 (2)0.2222 (2)0.0622 (6)
H140.99370.81120.25520.075*
C150.8889 (2)0.6619 (2)0.29125 (19)0.0602 (5)
H150.88500.68430.37150.072*
C160.83055 (16)0.55359 (17)0.24359 (15)0.0448 (4)
H160.78840.50070.29220.054*
C210.63217 (16)0.17125 (15)0.03024 (13)0.0407 (4)
C220.69437 (18)0.07128 (16)0.09046 (15)0.0467 (4)
C240.5310 (2)0.0283 (2)0.20019 (19)0.0693 (7)
H240.49660.02100.25740.083*
C260.51877 (18)0.19772 (19)0.05775 (16)0.0492 (4)
C23A0.6426 (2)0.00145 (19)0.17485 (17)0.0618 (6)0.747 (4)
C25A0.4689 (2)0.1274 (3)0.14214 (19)0.0665 (7)0.747 (4)
H25A0.39130.14780.15990.080*0.747 (4)
F1A0.7017 (2)0.09064 (16)0.23597 (15)0.0758 (7)0.747 (4)
C23B0.6426 (2)0.00145 (19)0.17485 (17)0.0618 (6)0.25
H23B0.68620.06650.21570.074*0.253 (4)
C25B0.4689 (2)0.1274 (3)0.14214 (19)0.0665 (7)0.25
F2B0.3774 (5)0.1417 (8)0.1629 (6)0.099 (3)0.253 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0789 (4)0.0587 (3)0.0676 (3)0.0216 (3)0.0001 (3)0.0108 (2)
Cl20.0627 (3)0.0829 (4)0.0700 (4)0.0201 (3)0.0129 (3)0.0075 (3)
O10.0774 (9)0.0498 (7)0.0311 (6)0.0050 (6)0.0081 (6)0.0060 (5)
C10.0450 (8)0.0320 (7)0.0358 (7)0.0024 (6)0.0077 (6)0.0041 (6)
C20.0523 (9)0.0386 (8)0.0327 (7)0.0025 (7)0.0077 (6)0.0057 (6)
C30.0512 (9)0.0373 (8)0.0311 (7)0.0084 (7)0.0051 (6)0.0000 (6)
C110.0393 (8)0.0319 (7)0.0403 (8)0.0043 (6)0.0031 (6)0.0045 (6)
C120.0544 (10)0.0406 (9)0.0516 (10)0.0008 (8)0.0098 (8)0.0096 (7)
C130.0501 (10)0.0430 (9)0.0763 (14)0.0047 (8)0.0025 (9)0.0187 (9)
C140.0637 (12)0.0423 (10)0.0743 (14)0.0108 (9)0.0161 (10)0.0041 (9)
C150.0760 (14)0.0490 (11)0.0522 (11)0.0091 (10)0.0054 (10)0.0057 (9)
C160.0537 (10)0.0392 (8)0.0409 (8)0.0021 (7)0.0027 (7)0.0004 (7)
C210.0568 (10)0.0352 (8)0.0291 (7)0.0053 (7)0.0009 (6)0.0041 (6)
C220.0665 (11)0.0360 (8)0.0354 (8)0.0068 (8)0.0030 (7)0.0018 (6)
C240.0934 (17)0.0662 (14)0.0480 (11)0.0410 (13)0.0068 (11)0.0041 (10)
C260.0567 (10)0.0520 (10)0.0385 (8)0.0074 (8)0.0036 (7)0.0054 (7)
C23A0.0988 (18)0.0423 (10)0.0404 (10)0.0211 (10)0.0078 (10)0.0058 (8)
C25A0.0706 (15)0.0780 (15)0.0518 (11)0.0294 (12)0.0114 (10)0.0063 (11)
F1A0.1208 (17)0.0477 (9)0.0571 (10)0.0024 (9)0.0037 (10)0.0182 (7)
C23B0.0988 (18)0.0423 (10)0.0404 (10)0.0211 (10)0.0078 (10)0.0058 (8)
C25B0.0706 (15)0.0780 (15)0.0518 (11)0.0294 (12)0.0114 (10)0.0063 (11)
F2B0.066 (4)0.136 (6)0.103 (5)0.033 (4)0.045 (3)0.012 (4)
Geometric parameters (Å, º) top
Cl1—C221.727 (2)C14—C151.376 (3)
Cl2—C261.728 (2)C14—H140.9500
O1—C31.2198 (19)C15—C161.382 (3)
C1—C21.337 (2)C15—H150.9500
C1—C111.459 (2)C16—H160.9500
C1—H10.9500C21—C261.388 (3)
C2—C31.453 (2)C21—C221.388 (2)
C2—H20.9500C22—C23A1.391 (3)
C3—C211.516 (2)C24—C23A1.362 (4)
C11—C161.391 (2)C24—C25A1.370 (4)
C11—C121.398 (2)C24—H240.9500
C12—C131.380 (3)C26—C25A1.383 (3)
C12—H120.9500C23A—F1A1.317 (3)
C13—C141.377 (3)C25A—H25A0.9500
C13—H130.9500
C2—C1—C11127.65 (15)C16—C15—H15120.0
C2—C1—H1116.2C15—C16—C11120.87 (18)
C11—C1—H1116.2C15—C16—H16119.6
C1—C2—C3122.74 (15)C11—C16—H16119.6
C1—C2—H2118.6C26—C21—C22117.70 (16)
C3—C2—H2118.6C26—C21—C3121.83 (15)
O1—C3—C2122.47 (16)C22—C21—C3120.45 (16)
O1—C3—C21119.07 (15)C21—C22—C23A120.0 (2)
C2—C3—C21118.46 (13)C21—C22—Cl1120.01 (14)
C16—C11—C12118.46 (16)C23A—C22—Cl1119.97 (16)
C16—C11—C1117.86 (15)C23A—C24—C25A119.2 (2)
C12—C11—C1123.68 (15)C23A—C24—H24120.4
C13—C12—C11120.13 (18)C25A—C24—H24120.4
C13—C12—H12119.9C25A—C26—C21121.5 (2)
C11—C12—H12119.9C25A—C26—Cl2119.02 (18)
C14—C13—C12120.62 (19)C21—C26—Cl2119.52 (14)
C14—C13—H13119.7F1A—C23A—C24117.6 (2)
C12—C13—H13119.7F1A—C23A—C22120.9 (2)
C15—C14—C13119.97 (19)C24—C23A—C22121.5 (2)
C15—C14—H14120.0C24—C25A—C26120.2 (2)
C13—C14—H14120.0C24—C25A—H25A119.9
C14—C15—C16119.9 (2)C26—C25A—H25A119.9
C14—C15—H15120.0
C11—C1—C2—C3178.53 (15)C26—C21—C22—C23A0.1 (2)
C1—C2—C3—O1177.72 (17)C3—C21—C22—C23A178.32 (15)
C1—C2—C3—C211.8 (2)C26—C21—C22—Cl1178.77 (13)
C2—C1—C11—C16175.07 (17)C3—C21—C22—Cl12.8 (2)
C2—C1—C11—C124.7 (3)C22—C21—C26—C25A0.0 (3)
C16—C11—C12—C130.8 (3)C3—C21—C26—C25A178.42 (17)
C1—C11—C12—C13179.44 (16)C22—C21—C26—Cl2179.90 (12)
C11—C12—C13—C141.6 (3)C3—C21—C26—Cl21.7 (2)
C12—C13—C14—C150.8 (3)C25A—C24—C23A—F1A177.08 (19)
C13—C14—C15—C160.8 (3)C25A—C24—C23A—C220.8 (3)
C14—C15—C16—C111.6 (3)C21—C22—C23A—F1A177.52 (17)
C12—C11—C16—C150.8 (3)Cl1—C22—C23A—F1A1.4 (3)
C1—C11—C16—C15178.99 (17)C21—C22—C23A—C240.3 (3)
O1—C3—C21—C2692.4 (2)Cl1—C22—C23A—C24179.16 (16)
C2—C3—C21—C2688.0 (2)C23A—C24—C25A—C260.9 (3)
O1—C3—C21—C2285.9 (2)C21—C26—C25A—C240.5 (3)
C2—C3—C21—C2293.60 (19)Cl2—C26—C25A—C24179.59 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···O1i0.952.503.399 (2)158
C16—H16···O1i0.952.573.440 (2)153
Symmetry code: (i) x, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC15H9Cl2FO
Mr295.12
Crystal system, space groupMonoclinic, P21/c
Temperature (K)200
a, b, c (Å)11.3390 (3), 10.3896 (3), 11.3930 (3)
β (°) 97.078 (1)
V3)1331.95 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.49
Crystal size (mm)0.49 × 0.34 × 0.17
Data collection
DiffractometerBruker APEXII CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.798, 0.920
No. of measured, independent and
observed [I > 2σ(I)] reflections
23002, 3329, 2742
Rint0.025
(sin θ/λ)max1)0.669
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.111, 1.04
No. of reflections3329
No. of parameters182
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.58, 0.60

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···O1i0.952.503.399 (2)157.9
C16—H16···O1i0.952.573.440 (2)153.0
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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