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ISSN: 2056-9890

(1E,4E)-1,5-Bis(4-methyl­phen­yl)penta-1,4-dien-3-one

aGovernment College University, Department of Chemistry, Lahore, Pakistan, and bUniversity of Sargodha, Department of Physics, Sargodha, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 18 June 2008; accepted 1 July 2008; online 5 July 2008)

The title compound, C19H18O, crystallizes in a non-centrosymmetric space group although the mol­ecule has no chiral centre. The dihedral angle between the aromatic rings is 20.43 (13)°. The structure is stabilized by two intra­molecular hydrogen bonds, and by four ππ and three C—H⋯π inter­actions between the aromatic rings. The perpendicular distances between the centroids of the rings involved in the ππ inter­actions have values of 1.996, 2.061, 2.181 and 2.189 Å.

Related literature

For related literature, see: Butcher et al. (2006[Butcher, R. J., Yathirajan, H. S., Sarojini, B. K., Narayana, B. & Vijaya Raj, K. K. (2006). Acta Cryst. E62, o1973-o1975.]); Conard & Dolliver (1943[Conard, C. R. & Dolliver, M. A. (1943). Org. Synth Coll. Vol. II, pp. 167-168.]); Harrison et al. (2006[Harrison, W. T. A., Sarojini, B. K., Vijaya Raj, K. K., Yathirajan, H. S. & Narayana, B. (2006). Acta Cryst. E62, o1522-o1523.]).

[Scheme 1]

Experimental

Crystal data
  • C19H18O

  • Mr = 262.33

  • Monoclinic, C 2

  • a = 19.937 (2) Å

  • b = 5.8637 (5) Å

  • c = 14.9207 (14) Å

  • β = 121.001 (3)°

  • V = 1495.1 (2) Å3

  • Z = 4

  • Mo Kα radiation radiation

  • μ = 0.07 mm−1

  • T = 296 (2) K

  • 0.25 × 0.20 × 0.15 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.980, Tmax = 0.988

  • 9611 measured reflections

  • 2288 independent reflections

  • 1800 reflections with I > 2σ(I)

  • Rint = 0.024

Refinement
  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.137

  • S = 1.04

  • 2288 reflections

  • 183 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.22 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

CgA and CgB are the centroids of the C4–C9 and C13–C18 rings, respectively.

D—H⋯A D—H H⋯A DA D—H⋯A
C3—H3⋯O1 0.93 2.49 2.817 (4) 101
C12—H12⋯O1 0.93 2.48 2.819 (3) 102
C5—H5⋯CgAi 0.93 2.82 3.523 (3) 133
C9—H9⋯CgBii 0.93 2.89 3.604 (3) 134
C18—H18⋯CgBiii 0.93 2.95 3.621 (3) 131
Symmetry codes: (i) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z]; (ii) -x+1, y, -z+1; (iii) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+1].

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information


Comment top

The chalcones are being synthesized since long for various applications. The title compound (I) differs from 1,5-Bis(4-methoxyphenyl)penta-1,4- dien-3-one (II) (Harrison et al., 2006) and 1,5-Bis(4-chlorophenyl)penta-1,4- dien-3-one (III) (Butcher et al., 2006) due the attachement of methyl group at para position instead of methoxy or chloro moieties. The authors have reported their nonlinear optical (NLO) activity as the compounds crystallize in non-centrosymmetric space groups. The title compound have a monoclinic crystal system and a non-centrosymmetric space group C2. Therefore, it is assumed that this compound will also have nonlinear optical activity.

We compare the bond distances and bond angles realised in (I) with the corresponding values observed in (II) and (III). The central portion of (I) shows double and single bonds originating from O1-atom and five-C-atom behave like a backbone. In (I), the bond distance O1==C1 is 1.211 (4) Å, greater than 1.170 (12) Å (III) but shorter than 1.230 (6) Å as in (II). The bond distances C1—C2 = 1.480 (3) Å, C2==C3 = 1.329 (3) Å, C3—C4 = 1.465 (3) Å are observed in (I), in (II) and (III) the corresponding values are [1.476 (4), 1.318 (5), 1.475 (4) Å] and [1.579 (10), 1.239 (7), 1.502 (7) Å], respectively. The range of bond angles for backbone C-atoms in (I) is 116.0 (2)°-127.8 (2)°, whereas in (II) and (III), the range is 123.8 (5)°- 126.4 (4)° and 103.1 (9)°-128.5 (4)°, respectively. The dihedral angle between the aromatic rings A (C4—C9) and B (C13—C18) is 20.27 (13)°, which is less than 56.92 (9)° and 53.4 (5) as reported in (II) and (III), respectively. The title compound is stabilized due to two intramolecular H-bonding (Fig 1) and three C—H···π interactions as given in Table 1. There exist also ππ-interactions between the aromatic rings. The perpendicular distance between the centroids CgA and CgB [(CgA···CgAiv), symmetry code: iv = -x + 1/2, y - 1/2, -z], [(CgA···CgBv), symmetry code: v = -x + 1, y + 1, -z + 1], [(CgB···CgAii), symmetry code: ii = -x + 1, y, -z + 1] and [(CgB···CgBvi), symmetry code: vi = -x + 3/2, y - 1/2, -z + 1] have values of 1.996, 2.181, 2.061 and 2.189 Å, respectively.

Related literature top

For related literature, see: Butcher et al. (2006); Conard & Dolliver (1943); Harrison et al. (2006). [CgA and CgB are the centroids of the C4–C9 and C13–C18 rings, respectively.]

Experimental top

The title compound (I) was synthesized using the method of Conard & Dolliver, 1943. Sodium hydroxide (0.8 g, 0.0208 mmol) was dissolved in distilled water (10 ml) and ethanol (8 ml) in a round bottom flask. The solution was cooled to room temperature. Half of the mixture of p-tolualdehide (1 g, 0.00833 mmol) and acetone (0.24 g, 0.00417 mmol) added to the above solution and stirred at room temperature for 15 minute then the remaining mixture was added and stirred for 2 h under the same conditions. Yellow precipitate obtained was filtered and washed with cold water. The washed precipitate was crystallized in aceton under slow evaporation.

Refinement top

H-atoms were positioned geometrically, with C—H = 0.93 and 0.96 Å for aromatic and methyl H, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C), where x = 1.5 for methyl H, and x = 1.2 for other H atoms. Friedel pairs were averaged before the final refinement as the absolute configuration could not be determined unambiguously.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: APEX2 (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. ORTEP drawing of the title compound, with the atom numbering scheme. The thermal ellipsoids are drawn at the 50% probability level. H-atoms are shown by small circles of arbitrary radii. The intramolecular H-bonding is shown by dotted lines.
[Figure 2] Fig. 2. The packing figure (PLATON: Spek, 2003) which shows the stacking of molecules in a unit cell.
(1E,4E)-1,5-Bis(4-methylphenyl)penta-1,4-dien-3-one top
Crystal data top
C19H18OF(000) = 560
Mr = 262.33Dx = 1.165 Mg m3
Monoclinic, C2Mo Kα radiation radiation, λ = 0.71073 Å
Hall symbol: C 2yCell parameters from 3173 reflections
a = 19.937 (2) Åθ = 2.1–29.6°
b = 5.8637 (5) ŵ = 0.07 mm1
c = 14.9207 (14) ÅT = 296 K
β = 121.001 (3)°Prism, yellow
V = 1495.1 (2) Å30.25 × 0.20 × 0.15 mm
Z = 4
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2288 independent reflections
Radiation source: fine-focus sealed tube1800 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
Detector resolution: 7.40 pixels mm-1θmax = 29.6°, θmin = 2.1°
ω scansh = 2627
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
k = 84
Tmin = 0.980, Tmax = 0.988l = 2018
9611 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.048H-atom parameters constrained
wR(F2) = 0.137 w = 1/[σ2(Fo2) + (0.0717P)2 + 0.4143P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
2288 reflectionsΔρmax = 0.22 e Å3
183 parametersΔρmin = 0.21 e Å3
1 restraintAbsolute structure: Flack (1983), 726 Friedel pairs
Primary atom site location: structure-invariant direct methods
Crystal data top
C19H18OV = 1495.1 (2) Å3
Mr = 262.33Z = 4
Monoclinic, C2Mo Kα radiation
a = 19.937 (2) ŵ = 0.07 mm1
b = 5.8637 (5) ÅT = 296 K
c = 14.9207 (14) Å0.25 × 0.20 × 0.15 mm
β = 121.001 (3)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2288 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
1800 reflections with I > 2σ(I)
Tmin = 0.980, Tmax = 0.988Rint = 0.024
9611 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0481 restraint
wR(F2) = 0.137H-atom parameters constrained
S = 1.04Δρmax = 0.22 e Å3
2288 reflectionsΔρmin = 0.21 e Å3
183 parametersAbsolute structure: Flack (1983), 726 Friedel pairs
Special details top

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) top
xyzUiso*/Ueq
O10.49937 (12)1.0189 (4)0.63720 (18)0.0745 (7)
C10.51762 (14)0.8202 (5)0.6423 (2)0.0495 (6)
C20.59839 (13)0.7416 (5)0.71598 (18)0.0470 (6)
H20.61150.59060.71320.056*
C30.65267 (13)0.8809 (4)0.78604 (17)0.0429 (5)
H30.63741.03080.78610.051*
C40.73402 (12)0.8232 (4)0.86323 (17)0.0383 (5)
C50.77901 (14)0.9756 (4)0.94391 (19)0.0469 (5)
H50.75761.11500.94600.056*
C60.85484 (15)0.9234 (5)1.0209 (2)0.0520 (6)
H60.88351.02781.07410.062*
C70.88884 (13)0.7179 (5)1.02006 (18)0.0482 (6)
C80.84507 (14)0.5688 (5)0.9386 (2)0.0523 (6)
H80.86720.43160.93550.063*
C90.76890 (13)0.6194 (4)0.86135 (18)0.0459 (6)
H90.74070.51570.80760.055*
C100.97104 (15)0.6567 (8)1.1064 (2)0.0751 (10)
H10A0.98020.71631.17170.113*
H10B1.00820.72111.09100.113*
H10C0.97670.49381.11120.113*
C110.46029 (14)0.6396 (4)0.57787 (19)0.0474 (6)
H110.47750.49070.58100.057*
C120.38539 (13)0.6886 (5)0.51634 (17)0.0439 (5)
H120.37130.83980.51640.053*
C130.32183 (13)0.5337 (4)0.44805 (17)0.0405 (5)
C140.33464 (13)0.3184 (4)0.41838 (19)0.0447 (5)
H140.38560.26730.44440.054*
C150.27265 (14)0.1824 (4)0.35119 (18)0.0444 (5)
H150.28220.04100.33180.053*
C160.19537 (14)0.2537 (4)0.31160 (18)0.0432 (5)
C170.18269 (14)0.4658 (4)0.34177 (19)0.0455 (5)
H170.13180.51590.31670.055*
C180.24460 (13)0.6022 (4)0.40822 (18)0.0438 (5)
H180.23480.74380.42710.053*
C190.12788 (15)0.1027 (5)0.2395 (2)0.0596 (7)
H19A0.14470.00470.20650.089*
H19B0.08620.19440.18710.089*
H19C0.10970.02200.27900.089*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0515 (11)0.0599 (12)0.0763 (14)0.0052 (10)0.0073 (10)0.0046 (11)
C10.0385 (12)0.0582 (15)0.0410 (13)0.0011 (11)0.0128 (10)0.0008 (12)
C20.0365 (11)0.0545 (14)0.0420 (12)0.0027 (11)0.0146 (10)0.0004 (11)
C30.0392 (11)0.0471 (12)0.0406 (12)0.0013 (11)0.0194 (10)0.0008 (10)
C40.0339 (10)0.0444 (11)0.0356 (11)0.0026 (9)0.0171 (9)0.0000 (10)
C50.0474 (13)0.0427 (11)0.0500 (13)0.0041 (10)0.0247 (11)0.0086 (11)
C60.0436 (13)0.0587 (15)0.0446 (13)0.0127 (12)0.0162 (11)0.0164 (12)
C70.0342 (11)0.0621 (15)0.0434 (13)0.0031 (11)0.0164 (10)0.0021 (13)
C80.0422 (12)0.0522 (14)0.0591 (15)0.0055 (11)0.0236 (11)0.0037 (13)
C90.0398 (12)0.0466 (12)0.0456 (13)0.0060 (10)0.0179 (10)0.0144 (11)
C100.0380 (13)0.098 (3)0.0664 (18)0.0033 (17)0.0103 (13)0.0052 (19)
C110.0432 (12)0.0502 (13)0.0443 (13)0.0016 (11)0.0193 (10)0.0002 (11)
C120.0431 (12)0.0469 (11)0.0406 (12)0.0004 (11)0.0208 (10)0.0016 (10)
C130.0415 (11)0.0430 (11)0.0341 (11)0.0038 (10)0.0173 (9)0.0034 (10)
C140.0403 (11)0.0485 (12)0.0451 (12)0.0046 (10)0.0219 (10)0.0066 (11)
C150.0518 (13)0.0388 (10)0.0449 (12)0.0001 (10)0.0265 (11)0.0004 (10)
C160.0461 (12)0.0426 (11)0.0384 (11)0.0039 (10)0.0201 (10)0.0035 (9)
C170.0368 (11)0.0469 (12)0.0483 (13)0.0041 (10)0.0187 (10)0.0076 (11)
C180.0445 (12)0.0418 (11)0.0459 (13)0.0042 (10)0.0238 (10)0.0041 (10)
C190.0507 (14)0.0595 (16)0.0560 (15)0.0103 (13)0.0185 (12)0.0065 (14)
Geometric parameters (Å, º) top
O1—C11.211 (4)C10—H10C0.9600
C1—C21.480 (3)C11—C121.320 (3)
C1—C111.490 (4)C11—H110.9300
C2—C31.329 (3)C12—C131.463 (3)
C2—H20.9300C12—H120.9300
C3—C41.465 (3)C13—C181.394 (3)
C3—H30.9300C13—C141.404 (3)
C4—C91.390 (3)C14—C151.375 (3)
C4—C51.393 (3)C14—H140.9300
C5—C61.382 (4)C15—C161.400 (3)
C5—H50.9300C15—H150.9300
C6—C71.386 (4)C16—C171.390 (3)
C6—H60.9300C16—C191.503 (3)
C7—C81.383 (4)C17—C181.373 (3)
C7—C101.516 (3)C17—H170.9300
C8—C91.385 (3)C18—H180.9300
C8—H80.9300C19—H19A0.9600
C9—H90.9300C19—H19B0.9600
C10—H10A0.9600C19—H19C0.9600
C10—H10B0.9600
O1—C1—C2121.5 (3)H10B—C10—H10C109.5
O1—C1—C11122.5 (2)C12—C11—C1120.7 (2)
C2—C1—C11116.0 (2)C12—C11—H11119.6
C3—C2—C1121.8 (2)C1—C11—H11119.6
C3—C2—H2119.1C11—C12—C13127.8 (2)
C1—C2—H2119.1C11—C12—H12116.1
C2—C3—C4126.8 (2)C13—C12—H12116.1
C2—C3—H3116.6C18—C13—C14117.7 (2)
C4—C3—H3116.6C18—C13—C12119.2 (2)
C9—C4—C5117.6 (2)C14—C13—C12123.0 (2)
C9—C4—C3123.1 (2)C15—C14—C13120.7 (2)
C5—C4—C3119.4 (2)C15—C14—H14119.7
C6—C5—C4121.2 (2)C13—C14—H14119.7
C6—C5—H5119.4C14—C15—C16121.0 (2)
C4—C5—H5119.4C14—C15—H15119.5
C5—C6—C7121.1 (2)C16—C15—H15119.5
C5—C6—H6119.5C17—C16—C15118.3 (2)
C7—C6—H6119.5C17—C16—C19120.9 (2)
C8—C7—C6117.9 (2)C15—C16—C19120.7 (2)
C8—C7—C10120.9 (3)C18—C17—C16120.6 (2)
C6—C7—C10121.2 (3)C18—C17—H17119.7
C7—C8—C9121.4 (3)C16—C17—H17119.7
C7—C8—H8119.3C17—C18—C13121.7 (2)
C9—C8—H8119.3C17—C18—H18119.2
C8—C9—C4120.9 (2)C13—C18—H18119.2
C8—C9—H9119.6C16—C19—H19A109.5
C4—C9—H9119.6C16—C19—H19B109.5
C7—C10—H10A109.5H19A—C19—H19B109.5
C7—C10—H10B109.5C16—C19—H19C109.5
H10A—C10—H10B109.5H19A—C19—H19C109.5
C7—C10—H10C109.5H19B—C19—H19C109.5
H10A—C10—H10C109.5
O1—C1—C2—C36.0 (4)O1—C1—C11—C124.0 (4)
C11—C1—C2—C3172.2 (2)C2—C1—C11—C12174.1 (2)
C1—C2—C3—C4179.6 (2)C1—C11—C12—C13179.6 (2)
C2—C3—C4—C911.2 (4)C11—C12—C13—C18164.8 (2)
C2—C3—C4—C5167.6 (2)C11—C12—C13—C1416.6 (4)
C9—C4—C5—C61.7 (4)C18—C13—C14—C150.8 (3)
C3—C4—C5—C6177.1 (2)C12—C13—C14—C15177.9 (2)
C4—C5—C6—C70.4 (4)C13—C14—C15—C160.7 (3)
C5—C6—C7—C81.3 (4)C14—C15—C16—C170.1 (3)
C5—C6—C7—C10177.9 (3)C14—C15—C16—C19179.0 (2)
C6—C7—C8—C91.6 (4)C15—C16—C17—C180.4 (3)
C10—C7—C8—C9177.6 (3)C19—C16—C17—C18179.5 (2)
C7—C8—C9—C40.2 (4)C16—C17—C18—C130.3 (3)
C5—C4—C9—C81.5 (4)C14—C13—C18—C170.3 (3)
C3—C4—C9—C8177.4 (2)C12—C13—C18—C17178.4 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···O10.932.492.817 (4)101
C12—H12···O10.932.482.819 (3)102
C5—H5···CgAi0.932.823.523 (3)133
C9—H9···CgBii0.932.893.604 (3)134
C18—H18···CgBiii0.932.953.621 (3)131
Symmetry codes: (i) x+1/2, y+1/2, z; (ii) x+1, y, z+1; (iii) x+3/2, y+1/2, z+1.

Experimental details

Crystal data
Chemical formulaC19H18O
Mr262.33
Crystal system, space groupMonoclinic, C2
Temperature (K)296
a, b, c (Å)19.937 (2), 5.8637 (5), 14.9207 (14)
β (°) 121.001 (3)
V3)1495.1 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.07
Crystal size (mm)0.25 × 0.20 × 0.15
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.980, 0.988
No. of measured, independent and
observed [I > 2σ(I)] reflections
9611, 2288, 1800
Rint0.024
(sin θ/λ)max1)0.695
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.137, 1.04
No. of reflections2288
No. of parameters183
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.22, 0.21
Absolute structureFlack (1983), 726 Friedel pairs

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003), WinGX (Farrugia, 1999) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3···O10.932.492.817 (4)101
C12—H12···O10.932.482.819 (3)102
C5—H5···CgAi0.932.823.523 (3)133
C9—H9···CgBii0.932.893.604 (3)134
C18—H18···CgBiii0.932.953.621 (3)131
Symmetry codes: (i) x+1/2, y+1/2, z; (ii) x+1, y, z+1; (iii) x+3/2, y+1/2, z+1.
 

Acknowledgements

MNA gratefully acknowledges the Higher Education Commision, Islamabad, Pakistan, for providing a scholarship under the Indigenous PhD Programme (PIN 042-120607-PS2-183).

References

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