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Acta Crystallogr Sect E Struct Rep Online. 2008 February 1; 64(Pt 2): o490.
Published online 2008 January 23. doi:  10.1107/S1600536808001517
PMCID: PMC2960402

9-n-Butyl-9,9′-bi[9H-fluorene]

Abstract

In the title compound, C30H26, the dihedral angle between the two fluorene ring systems is 61.75 (4)°.

Related literature

For general background, see: Muller et al. (2003 [triangle]); Murahashi & Moritani (1967 [triangle]).

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Object name is e-64-0o490-scheme1.jpg

Experimental

Crystal data

  • C30H26
  • M r = 386.51
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-0o490-efi1.jpg
  • a = 27.164 (5) Å
  • b = 8.6369 (17) Å
  • c = 19.232 (4) Å
  • β = 104.28 (3)°
  • V = 4372.7 (15) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 0.07 mm−1
  • T = 298 (2) K
  • 0.46 × 0.38 × 0.35 mm

Data collection

  • Bruker SMART 1000 CCD area-detector diffractometer
  • Absorption correction: none
  • 20365 measured reflections
  • 4970 independent reflections
  • 2859 reflections with I > 2σ(I)
  • R int = 0.031

Refinement

  • R[F 2 > 2σ(F 2)] = 0.039
  • wR(F 2) = 0.122
  • S = 1.06
  • 4970 reflections
  • 273 parameters
  • H-atom parameters constrained
  • Δρmax = 0.18 e Å−3
  • Δρmin = −0.14 e Å−3

Data collection: SMART (Bruker, 2001 [triangle]); cell refinement: SAINT (Bruker, 2001 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and publCIF (Westrip, 2008 [triangle]).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808001517/xu2394sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808001517/xu2394Isup2.hkl

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

Acknowledgments

The authors thank the National Natural Science Foundation of China (20674070) and the Natural Science Foundation of Zhejiang Province (R404109).

supplementary crystallographic information

Comment

Fluorene derivatives, including polyfluorenes and oligofluorenes, remain a subject of intense investigation in recent years because they are very promising candidates for blue light-emitting materials in organic light-emitting devices (Muller et al., 2003). The title compound, 9-n-butyl-9,9'-bi(9H-fluorene)(hereinafter abbreviated to bbf), is one of bifluorene derivatives (Murahashi & Moritani, 1967).

The asymmetric unit of the title compound contains only one bbf molecule (Fig. 1). Two fluorene rings are linked together through their 9-position carbon atoms (C1 and C14). The dihedral angle between the two fluorene rings is 61.75 (4)°. The centroid to centroid distance between stacked fluorene rings is ca 5.92 Å, which is very long and prevents π-π stacking (Fig. 2). All bond lengths and angles are normal.

Experimental

All chemicals were of reagent grade quality obtained from commercial sources and used as received, unless stated otherwise. n-Butylithium (8 ml, 2.5 M, 20 mmol) was added to fluorene (1.66 g, 10 mmol) in 40 ml dry tetrahydrofuran under nitrogen at -78 °C. Subsequently, BF3Et2O (0.21 g, 2 mmol) was added. Kept it for 1 h, and warmed it to room temperature and stirred it overnight. After reaction completion, solvent was evaporated under reduced pressure. The crude products were purified by column chromatography (silica gel) using n-hexane/dichloromethane as eluent. The title compound was obtained as white solid in 30% yield. Colorless single crystals were grown from slow evaporation of a saturated CH2Cl2 solution of the compound.

Refinement

H atoms were positioned geometrically and treated as riding, with C—H = 0.93 (aromatic), 0.97 (methylene) or 0.96 Å (methyl), Uiso(H) = 1.5Ueq(C) for methyl or Uiso(H) = 1.2Ueq(C) for others.

Figures

Fig. 1.
The molecular structure showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are shown as small spheres of arbitrary radii.
Fig. 2.
Partial packing view, H atoms are omitted for clarity.

Crystal data

C30H26F000 = 1648
Mr = 386.51Dx = 1.174 Mg m3
Monoclinic, C2/cMo Kα radiation λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 12421 reflections
a = 27.164 (5) Åθ = 3.0–27.4º
b = 8.6369 (17) ŵ = 0.07 mm1
c = 19.232 (4) ÅT = 298 (2) K
β = 104.28 (3)ºChunk, colorless
V = 4372.7 (15) Å30.46 × 0.38 × 0.35 mm
Z = 8

Data collection

Bruker SMART 1000 CCD area-detector diffractometer2859 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.031
Monochromator: graphiteθmax = 27.4º
T = 298(2) Kθmin = 3.1º
[var phi] and ω scansh = −35→35
Absorption correction: nonek = −11→10
20365 measured reflectionsl = −24→24
4970 independent reflections

Refinement

Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.039  w = 1/[σ2(Fo2) + (0.0595P)2 + 0.3188P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.122(Δ/σ)max < 0.001
S = 1.06Δρmax = 0.18 e Å3
4970 reflectionsΔρmin = −0.14 e Å3
273 parametersExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0038 (4)
Secondary atom site location: difference Fourier map

Special details

Experimental. 1H NMR (500 MHz, δ in p.p.m., CDCl3): 0.68-0.74 (m, 5H), 0.17-1.22 (m, 2H), 2.55-2.58 (m, 2H), 4.58 (s, 1H), 6.76 (d, 2H, J = 7.00 Hz), 6.86 (d, 2H, J = 7.00 Hz), 6.97 (t, 2H, J = 7.50 Hz), 7.08 (t, 2H, J = 7.50 Hz), 7.17-7.23 (m, 4H), 7.49 (d, 2H, J = 7.50 Hz); 13C NMR (125 MHz, δ in p.p.m., CDCl3): 14.15, 23.35, 26.45, 38.86, 55.48, 57.75, 119.39,119.62, 123.40, 125.84, 126.00, 126.90, 127.35, 141.59, 142.19, 144.37, 148.57; MS (EI): calcd for C30H26, 386.2; found, 386 (M+), 326, 313, 300, 221 (100), 179, 165, 152.
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
C10.11948 (5)0.49033 (14)−0.00529 (6)0.0446 (3)
C20.09626 (5)0.61937 (15)−0.05656 (7)0.0482 (3)
C30.05151 (6)0.61827 (19)−0.11011 (7)0.0622 (4)
H30.03220.5285−0.12030.075*
C40.03611 (7)0.7533 (2)−0.14825 (8)0.0765 (5)
H40.00580.7547−0.18360.092*
C50.06533 (8)0.8858 (2)−0.13425 (9)0.0788 (5)
H50.05460.9751−0.16070.095*
C60.11021 (7)0.88774 (17)−0.08167 (9)0.0669 (4)
H60.12990.9770−0.07280.080*
C70.12544 (5)0.75404 (15)−0.04213 (7)0.0501 (3)
C80.16888 (5)0.72391 (15)0.01911 (7)0.0492 (3)
C90.20847 (6)0.81905 (18)0.05433 (9)0.0648 (4)
H90.21090.92040.03920.078*
C100.24415 (6)0.7601 (2)0.11223 (9)0.0730 (5)
H100.27070.82270.13650.088*
C110.24097 (6)0.6098 (2)0.13449 (8)0.0679 (4)
H110.26530.57250.17370.082*
C120.20198 (5)0.51323 (17)0.09921 (7)0.0562 (4)
H120.20030.41130.11410.067*
C130.16563 (5)0.57100 (14)0.04155 (6)0.0453 (3)
C140.08081 (5)0.43871 (14)0.03910 (7)0.0481 (3)
H140.04980.40140.00550.058*
C150.06633 (5)0.56906 (16)0.08363 (7)0.0518 (3)
C160.04276 (5)0.71006 (18)0.06246 (9)0.0617 (4)
H160.03420.73840.01430.074*
C170.03222 (6)0.8079 (2)0.11398 (10)0.0757 (5)
H170.01670.90280.10020.091*
C180.04449 (7)0.7664 (2)0.18550 (10)0.0828 (5)
H180.03710.83370.21930.099*
C190.06752 (7)0.6270 (2)0.20742 (9)0.0744 (5)
H190.07550.59930.25560.089*
C200.07864 (5)0.52777 (18)0.15625 (7)0.0566 (4)
C210.09993 (5)0.37098 (17)0.16385 (7)0.0553 (4)
C220.11628 (6)0.2786 (2)0.22436 (8)0.0694 (4)
H220.11700.31760.26970.083*
C230.13134 (7)0.1289 (2)0.21644 (10)0.0774 (5)
H230.14290.06700.25670.093*
C240.12937 (7)0.07014 (19)0.14925 (10)0.0768 (5)
H240.1392−0.03170.14460.092*
C250.11283 (6)0.16108 (17)0.08828 (8)0.0661 (4)
H250.11090.11960.04300.079*
C260.09925 (5)0.31399 (16)0.09538 (7)0.0519 (3)
C270.13491 (5)0.35210 (15)−0.04660 (7)0.0525 (3)
H27A0.15310.2773−0.01210.063*
H27B0.10430.3022−0.07420.063*
C280.16785 (6)0.39514 (15)−0.09723 (7)0.0558 (4)
H28A0.15010.4721−0.13100.067*
H28B0.19900.4421−0.06950.067*
C290.18128 (7)0.26016 (17)−0.13865 (8)0.0685 (4)
H29A0.15030.2082−0.16350.082*
H29B0.20140.1869−0.10520.082*
C300.21068 (8)0.3067 (2)−0.19310 (9)0.0881 (6)
H30A0.19080.3783−0.22690.132*
H30B0.21770.2164−0.21810.132*
H30C0.24200.3550−0.16880.132*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0415 (7)0.0482 (7)0.0460 (7)−0.0060 (6)0.0142 (5)−0.0020 (6)
C20.0433 (7)0.0593 (8)0.0459 (7)−0.0001 (6)0.0186 (6)0.0001 (6)
C30.0508 (9)0.0868 (11)0.0499 (8)0.0004 (8)0.0139 (7)0.0039 (8)
C40.0623 (11)0.1144 (15)0.0535 (9)0.0212 (10)0.0157 (8)0.0162 (10)
C50.0905 (14)0.0866 (12)0.0679 (10)0.0336 (11)0.0358 (10)0.0248 (10)
C60.0836 (12)0.0559 (8)0.0704 (10)0.0098 (8)0.0365 (9)0.0072 (8)
C70.0529 (8)0.0493 (8)0.0549 (8)0.0031 (6)0.0260 (6)0.0012 (6)
C80.0473 (8)0.0491 (7)0.0567 (8)−0.0060 (6)0.0232 (6)−0.0071 (6)
C90.0626 (10)0.0559 (8)0.0801 (10)−0.0169 (7)0.0258 (8)−0.0134 (8)
C100.0554 (10)0.0829 (12)0.0798 (11)−0.0220 (8)0.0146 (9)−0.0215 (9)
C110.0441 (9)0.0922 (12)0.0640 (9)−0.0055 (8)0.0068 (7)−0.0079 (9)
C120.0448 (8)0.0635 (8)0.0600 (8)−0.0021 (7)0.0123 (6)0.0001 (7)
C130.0383 (7)0.0513 (7)0.0494 (7)−0.0032 (6)0.0169 (6)−0.0062 (6)
C140.0437 (7)0.0556 (7)0.0470 (7)−0.0109 (6)0.0148 (6)−0.0044 (6)
C150.0368 (7)0.0645 (8)0.0575 (8)−0.0096 (6)0.0182 (6)−0.0080 (7)
C160.0473 (8)0.0704 (9)0.0729 (9)−0.0019 (7)0.0254 (7)−0.0040 (8)
C170.0625 (11)0.0751 (11)0.0997 (13)0.0026 (8)0.0394 (9)−0.0123 (10)
C180.0761 (12)0.0938 (13)0.0885 (13)−0.0032 (10)0.0390 (10)−0.0320 (11)
C190.0682 (11)0.0985 (13)0.0610 (9)−0.0059 (10)0.0248 (8)−0.0185 (9)
C200.0422 (8)0.0766 (10)0.0537 (8)−0.0100 (7)0.0172 (6)−0.0111 (7)
C210.0441 (8)0.0723 (9)0.0510 (8)−0.0129 (7)0.0146 (6)−0.0014 (7)
C220.0606 (10)0.0949 (12)0.0529 (8)−0.0117 (9)0.0147 (7)0.0030 (9)
C230.0701 (11)0.0909 (12)0.0723 (11)−0.0040 (9)0.0199 (9)0.0229 (10)
C240.0811 (12)0.0638 (10)0.0934 (13)−0.0049 (9)0.0365 (10)0.0171 (10)
C250.0790 (11)0.0602 (9)0.0667 (9)−0.0149 (8)0.0325 (8)0.0007 (8)
C260.0475 (8)0.0594 (8)0.0524 (8)−0.0146 (6)0.0191 (6)−0.0021 (7)
C270.0569 (9)0.0514 (7)0.0531 (7)−0.0082 (6)0.0208 (6)−0.0051 (6)
C280.0611 (9)0.0551 (8)0.0562 (8)−0.0035 (7)0.0242 (7)−0.0029 (7)
C290.0848 (12)0.0617 (9)0.0693 (10)0.0068 (8)0.0389 (9)−0.0003 (8)
C300.1143 (16)0.0845 (12)0.0849 (12)0.0179 (11)0.0617 (11)0.0060 (10)

Geometric parameters (Å, °)

C1—C21.5183 (18)C16—H160.9300
C1—C131.5203 (17)C17—C181.380 (2)
C1—C271.5481 (18)C17—H170.9300
C1—C141.5728 (18)C18—C191.374 (2)
C2—C31.386 (2)C18—H180.9300
C2—C71.3963 (18)C19—C201.393 (2)
C3—C41.386 (2)C19—H190.9300
C3—H30.9300C20—C211.466 (2)
C4—C51.381 (2)C21—C221.390 (2)
C4—H40.9300C21—C261.4018 (18)
C5—C61.379 (3)C22—C231.376 (2)
C5—H50.9300C22—H220.9300
C6—C71.3884 (19)C23—C241.377 (2)
C6—H60.9300C23—H230.9300
C7—C81.470 (2)C24—C251.391 (2)
C8—C91.3897 (19)C24—H240.9300
C8—C131.3989 (18)C25—C261.387 (2)
C9—C101.381 (2)C25—H250.9300
C9—H90.9300C27—C281.5222 (19)
C10—C111.376 (2)C27—H27A0.9700
C10—H100.9300C27—H27B0.9700
C11—C121.387 (2)C28—C291.5067 (19)
C11—H110.9300C28—H28A0.9700
C12—C131.3833 (19)C28—H28B0.9700
C12—H120.9300C29—C301.520 (2)
C14—C261.5217 (19)C29—H29A0.9700
C14—C151.5237 (18)C29—H29B0.9700
C14—H140.9800C30—H30A0.9600
C15—C161.389 (2)C30—H30B0.9600
C15—C201.3997 (19)C30—H30C0.9600
C16—C171.385 (2)
C2—C1—C13101.43 (10)C18—C17—C16120.85 (17)
C2—C1—C27110.77 (10)C18—C17—H17119.6
C13—C1—C27111.68 (11)C16—C17—H17119.6
C2—C1—C14109.53 (10)C19—C18—C17120.85 (16)
C13—C1—C14111.83 (10)C19—C18—H18119.6
C27—C1—C14111.19 (10)C17—C18—H18119.6
C3—C2—C7120.28 (13)C18—C19—C20118.94 (16)
C3—C2—C1128.70 (13)C18—C19—H19120.5
C7—C2—C1110.96 (11)C20—C19—H19120.5
C2—C3—C4118.83 (15)C19—C20—C15120.53 (15)
C2—C3—H3120.6C19—C20—C21130.31 (14)
C4—C3—H3120.6C15—C20—C21109.04 (12)
C5—C4—C3120.68 (16)C22—C21—C26120.82 (15)
C5—C4—H4119.7C22—C21—C20130.58 (14)
C3—C4—H4119.7C26—C21—C20108.50 (12)
C6—C5—C4120.98 (15)C23—C22—C21119.27 (15)
C6—C5—H5119.5C23—C22—H22120.4
C4—C5—H5119.5C21—C22—H22120.4
C5—C6—C7118.81 (16)C22—C23—C24120.43 (16)
C5—C6—H6120.6C22—C23—H23119.8
C7—C6—H6120.6C24—C23—H23119.8
C6—C7—C2120.40 (14)C23—C24—C25120.85 (17)
C6—C7—C8131.13 (13)C23—C24—H24119.6
C2—C7—C8108.42 (11)C25—C24—H24119.6
C9—C8—C13120.53 (13)C26—C25—C24119.55 (15)
C9—C8—C7131.11 (13)C26—C25—H25120.2
C13—C8—C7108.36 (11)C24—C25—H25120.2
C10—C9—C8118.67 (14)C25—C26—C21118.99 (13)
C10—C9—H9120.7C25—C26—C14130.76 (12)
C8—C9—H9120.7C21—C26—C14110.21 (12)
C11—C10—C9120.90 (14)C28—C27—C1114.59 (11)
C11—C10—H10119.5C28—C27—H27A108.6
C9—C10—H10119.5C1—C27—H27A108.6
C10—C11—C12120.93 (15)C28—C27—H27B108.6
C10—C11—H11119.5C1—C27—H27B108.6
C12—C11—H11119.5H27A—C27—H27B107.6
C13—C12—C11118.90 (14)C29—C28—C27113.98 (11)
C13—C12—H12120.6C29—C28—H28A108.8
C11—C12—H12120.6C27—C28—H28A108.8
C12—C13—C8120.06 (12)C29—C28—H28B108.8
C12—C13—C1129.12 (12)C27—C28—H28B108.8
C8—C13—C1110.82 (11)H28A—C28—H28B107.7
C26—C14—C15102.04 (10)C28—C29—C30113.36 (13)
C26—C14—C1116.10 (11)C28—C29—H29A108.9
C15—C14—C1113.28 (10)C30—C29—H29A108.9
C26—C14—H14108.3C28—C29—H29B108.9
C15—C14—H14108.3C30—C29—H29B108.9
C1—C14—H14108.3H29A—C29—H29B107.7
C16—C15—C20119.68 (13)C29—C30—H30A109.5
C16—C15—C14130.33 (13)C29—C30—H30B109.5
C20—C15—C14109.96 (12)H30A—C30—H30B109.5
C17—C16—C15119.15 (15)C29—C30—H30C109.5
C17—C16—H16120.4H30A—C30—H30C109.5
C15—C16—H16120.4H30B—C30—H30C109.5
C13—C1—C2—C3−176.43 (13)C13—C1—C14—C1551.64 (14)
C27—C1—C2—C364.89 (18)C27—C1—C14—C15177.25 (11)
C14—C1—C2—C3−58.12 (17)C26—C14—C15—C16−173.67 (13)
C13—C1—C2—C71.02 (13)C1—C14—C15—C1660.77 (18)
C27—C1—C2—C7−117.65 (12)C26—C14—C15—C204.01 (14)
C14—C1—C2—C7119.34 (11)C1—C14—C15—C20−121.55 (12)
C7—C2—C3—C4−0.8 (2)C20—C15—C16—C170.5 (2)
C1—C2—C3—C4176.49 (13)C14—C15—C16—C17177.98 (14)
C2—C3—C4—C51.4 (2)C15—C16—C17—C18−0.5 (2)
C3—C4—C5—C6−0.6 (3)C16—C17—C18—C190.0 (3)
C4—C5—C6—C7−0.7 (2)C17—C18—C19—C200.4 (3)
C5—C6—C7—C21.3 (2)C18—C19—C20—C15−0.3 (2)
C5—C6—C7—C8−175.78 (14)C18—C19—C20—C21−175.94 (15)
C3—C2—C7—C6−0.6 (2)C16—C15—C20—C19−0.1 (2)
C1—C2—C7—C6−178.28 (12)C14—C15—C20—C19−178.06 (13)
C3—C2—C7—C8177.11 (12)C16—C15—C20—C21176.36 (12)
C1—C2—C7—C8−0.59 (15)C14—C15—C20—C21−1.60 (15)
C6—C7—C8—C9−2.2 (3)C19—C20—C21—C22−1.9 (3)
C2—C7—C8—C9−179.55 (14)C15—C20—C21—C22−177.95 (15)
C6—C7—C8—C13177.20 (14)C19—C20—C21—C26174.22 (15)
C2—C7—C8—C13−0.16 (15)C15—C20—C21—C26−1.79 (15)
C13—C8—C9—C10−0.6 (2)C26—C21—C22—C23−0.8 (2)
C7—C8—C9—C10178.69 (14)C20—C21—C22—C23174.97 (15)
C8—C9—C10—C110.5 (2)C21—C22—C23—C24−1.2 (3)
C9—C10—C11—C120.3 (3)C22—C23—C24—C250.9 (3)
C10—C11—C12—C13−0.9 (2)C23—C24—C25—C261.5 (3)
C11—C12—C13—C80.8 (2)C24—C25—C26—C21−3.4 (2)
C11—C12—C13—C1−179.59 (13)C24—C25—C26—C14179.11 (14)
C9—C8—C13—C120.0 (2)C22—C21—C26—C253.1 (2)
C7—C8—C13—C12−179.46 (12)C20—C21—C26—C25−173.51 (13)
C9—C8—C13—C1−179.69 (12)C22—C21—C26—C14−178.93 (13)
C7—C8—C13—C10.84 (14)C20—C21—C26—C144.46 (15)
C2—C1—C13—C12179.22 (13)C15—C14—C26—C25172.52 (14)
C27—C1—C13—C12−62.77 (17)C1—C14—C26—C25−63.80 (19)
C14—C1—C13—C1262.57 (17)C15—C14—C26—C21−5.13 (14)
C2—C1—C13—C8−1.12 (13)C1—C14—C26—C21118.54 (12)
C27—C1—C13—C8116.89 (12)C2—C1—C27—C2851.73 (15)
C14—C1—C13—C8−117.77 (12)C13—C1—C27—C28−60.53 (15)
C2—C1—C14—C26−177.61 (10)C14—C1—C27—C28173.78 (11)
C13—C1—C14—C26−65.98 (14)C1—C27—C28—C29−178.29 (13)
C27—C1—C14—C2659.63 (14)C27—C28—C29—C30175.53 (14)
C2—C1—C14—C15−59.99 (13)

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: XU2394).

References

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