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

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ISSN: 2056-9890

2-Acetyl-3,5,5,9-tetra­methyl-6,7,8,9-tetra­hydro-5H-benzo­cyclo­hepten-7-one

aLaboratoire de Chimie Biomoleculaire, Substances Naturelles et Réactivite', URAC16, Université Cadi Ayyad, Faculté des Sciences Semlalia, BP 2390, Bd My Abdellah, 40000 Marrakech, Morocco, and bLaboratoire de Chimie de Coordination, 205 route de Narbonne, 31077 Toulouse Cedex 04, France
*Correspondence e-mail: elassaba@gmail.com

(Received 22 November 2010; accepted 2 December 2010; online 8 December 2010)

The title compound, C17H22O2, was semi-synthesized from a mixture of α-atlantone (Z) and α-atlantone (E), which were isolated from the essential oil of the Atlas cedar (cedrus atlantica). The mol­ecule consists of fused six- and seven-membered rings. The seven-membered ring is in a screw-boat conformation.

Related literature

For the isolation of α-atlantone (Z) and its isomer α-atlantone (E), see: Plattier & Teisseire (1974[Plattier, M. & Teisseire, P. (1974). Recherches, 19, 131-144.]). For the reactivity of these ketones, see: Loughzail et al. (2009[Loughzail, M., Mazoir, N., Maya, C. M., Berraho, M., Benharref, A. & Bouhmaida, N. (2009). Acta Cryst. E65, o4.]); Mazoir et al. (2009[Mazoir, N., El Ammari, L., Bouhmaida, N., Dahaoui, S., Benharref, A. & Berraho, M. (2009). Acta Cryst. E65, o1269-o1270.]). For the isolation and reactivity of aryl-himachalene, see: Son Bredenberg & Erdtman (1961[Son Bredenberg, J. B. & Erdtman, H. (1961). Acta Chem. Scand. 15, 685-688]); Daunis et al. (1981[Daunis, J., Jaquier, R., Lopez, H. & Viallefont, Ph. (1981). J. Chem. Res. pp. 0639-0649]) For puckerint parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C17H22O2

  • Mr = 258.35

  • Monoclinic, P 21 /n

  • a = 7.7996 (6) Å

  • b = 18.3702 (10) Å

  • c = 9.9357 (6) Å

  • β = 99.616 (7)°

  • V = 1403.59 (16) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 180 K

  • 0.6 × 0.25 × 0.10 mm

Data collection
  • Oxford Diffraction Xcalibur Eos Gemini ultra diffractometer

  • 14554 measured reflections

  • 2855 independent reflections

  • 2196 reflections with I > 2σ(I)

  • Rint = 0.054

Refinement
  • R[F2 > 2σ(F2)] = 0.052

  • wR(F2) = 0.145

  • S = 1.08

  • 2855 reflections

  • 177 parameters

  • H-atom parameters constrained

  • Δρmax = 0.61 e Å−3

  • Δρmin = −0.29 e Å−3

Data collection: CrysAlis PRO (Oxford Diffraction, 2010[Oxford Diffraction (2010). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

α-Atlantone (Z) and α-atlantone (E) are the two isomeric sesquiterpene ketones which are constituents of the essential oil of Cedrus atlantica (3%) (Plattier & Teisseire 1974). The reactivity of these ketones has been studied by our team (Loughzail et al., 2009; Mazoir et al., 2009) in order to prepare products with high added value used in the cosmetics industry or in pharmacology. In the same context, we have synthesized the title compound (4-acethyl-arylhimachal-9-one) from a mixture of two isomers α- atlatones. The action of one equivalent of chloride cethyl in the presence of the Lewis acid AlCl3 on 2-methyl-6-(4-methylphenyl)hept-2-en-4-one, which was obtained from the mixture of two α- atlantones isomers (Mazoir et al., 2009) led to a yield of 35% at 4-acethyl-aryl-himachal-9-one, a derivative of the aryl-himachalene (Son Bredenberg & Erdtman, 1961; Daunis et al., 1981). The structure of this new derivative of aryl-himachalene was determined by 1H, 13C NMR spectral analysis and mass spectroscopy and confirmed by its single-crystal X-ray structure. The molecular structure of the title compound is shown in Fig.1. The benzene ring is essentially planar, whereas the seven-membered ring displays a screw boat conformation as indicated by Cremer & Pople (1975) puckering parameters QT = 0.9688 (2) Å and θ = 71.57 (10)°, φ2 = 168.10 (11)° and φ3 = -6.36 (4)°.

Related literature top

For the isolation of α-atlantone (Z) and its isomer α-atlantone (E), see: Plattier & Teisseire (1974). For the reactivity of these ketones, see: Loughzail et al. (2009); Mazoir et al. (2009). For the isolation and reactivity of aryl-himachalene, see: Son Bredenberg & Erdtman (1961); Daunis et al. (1981) For puckerint parameters, see: Cremer & Pople (1975).

Experimental top

In a reactor equipped with a stirring stick, containing 2 g (9,30 mmol) of 2-methyl-6-(4-methylphenyl) hept-2-en-4-one; 1,2 g of Lewis acid (AlCl3) and 30 ml of dichloromethane, we added drop wise with vigorous stirring 1 ml of acetyl chloride. The reaction mixture is heated to 323K in a water bath for one hour. After cooling, the reaction mixture was poured into 20 ml of iced water supplemented with 4 ml of concentrated hydrochloric acid. The reaction mixture was extracted three times with 20 ml of dichloromethane. The organic phases are combined, dried and evaporated under vacuum. Chromatography on silica gel of the residue obtained with hexane-ethyl acetate (98/2) as eluent, allowed us to isolate the pure 4-acethyl-aryl-himachal-9-one. The title compound was recrystallized in hexane.

Refinement top

All H atoms were fixed geometrically and treated as riding with C—H = 0.96 Å (methyl), 0.97 Å (methylene), 0.93Å (aromatic), 0.98Å (methine) with Uiso(H) = 1.2Ueq(C) or Uiso(H) = 1.5Ueq(methyl).

Structure description top

α-Atlantone (Z) and α-atlantone (E) are the two isomeric sesquiterpene ketones which are constituents of the essential oil of Cedrus atlantica (3%) (Plattier & Teisseire 1974). The reactivity of these ketones has been studied by our team (Loughzail et al., 2009; Mazoir et al., 2009) in order to prepare products with high added value used in the cosmetics industry or in pharmacology. In the same context, we have synthesized the title compound (4-acethyl-arylhimachal-9-one) from a mixture of two isomers α- atlatones. The action of one equivalent of chloride cethyl in the presence of the Lewis acid AlCl3 on 2-methyl-6-(4-methylphenyl)hept-2-en-4-one, which was obtained from the mixture of two α- atlantones isomers (Mazoir et al., 2009) led to a yield of 35% at 4-acethyl-aryl-himachal-9-one, a derivative of the aryl-himachalene (Son Bredenberg & Erdtman, 1961; Daunis et al., 1981). The structure of this new derivative of aryl-himachalene was determined by 1H, 13C NMR spectral analysis and mass spectroscopy and confirmed by its single-crystal X-ray structure. The molecular structure of the title compound is shown in Fig.1. The benzene ring is essentially planar, whereas the seven-membered ring displays a screw boat conformation as indicated by Cremer & Pople (1975) puckering parameters QT = 0.9688 (2) Å and θ = 71.57 (10)°, φ2 = 168.10 (11)° and φ3 = -6.36 (4)°.

For the isolation of α-atlantone (Z) and its isomer α-atlantone (E), see: Plattier & Teisseire (1974). For the reactivity of these ketones, see: Loughzail et al. (2009); Mazoir et al. (2009). For the isolation and reactivity of aryl-himachalene, see: Son Bredenberg & Erdtman (1961); Daunis et al. (1981) For puckerint parameters, see: Cremer & Pople (1975).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2010); cell refinement: CrysAlis PRO (Oxford Diffraction, 2010); data reduction: CrysAlis PRO (Oxford Diffraction, 2010); 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); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are represented as small spheres of arbitrary radii.
2-acetyl-3,5,5,9-tetramethyl-6,7,8,9-tetrahydro-5H-benzocyclohepten-7-one top
Crystal data top
C17H22O2F(000) = 560
Mr = 258.35Dx = 1.223 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2855 reflections
a = 7.7996 (6) Åθ = 3.5–29.3°
b = 18.3702 (10) ŵ = 0.08 mm1
c = 9.9357 (6) ÅT = 180 K
β = 99.616 (7)°Needle, colourless
V = 1403.59 (16) Å30.6 × 0.25 × 0.10 mm
Z = 4
Data collection top
Oxford Diffraction Xcalibur Eos Gemini ultra
diffractometer
2196 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.054
Graphite monochromatorθmax = 26.4°, θmin = 3.5°
Detector resolution: 16.1978 pixels mm-1h = 99
φ and ω scansk = 2222
14554 measured reflectionsl = 1213
2855 independent reflections
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)] = 0.052Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.145H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0729P)2 + 0.4506P]
where P = (Fo2 + 2Fc2)/3
2855 reflections(Δ/σ)max < 0.001
177 parametersΔρmax = 0.61 e Å3
0 restraintsΔρmin = 0.29 e Å3
Crystal data top
C17H22O2V = 1403.59 (16) Å3
Mr = 258.35Z = 4
Monoclinic, P21/nMo Kα radiation
a = 7.7996 (6) ŵ = 0.08 mm1
b = 18.3702 (10) ÅT = 180 K
c = 9.9357 (6) Å0.6 × 0.25 × 0.10 mm
β = 99.616 (7)°
Data collection top
Oxford Diffraction Xcalibur Eos Gemini ultra
diffractometer
2196 reflections with I > 2σ(I)
14554 measured reflectionsRint = 0.054
2855 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0520 restraints
wR(F2) = 0.145H-atom parameters constrained
S = 1.08Δρmax = 0.61 e Å3
2855 reflectionsΔρmin = 0.29 e Å3
177 parameters
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
C10.3403 (2)0.13187 (7)0.19877 (15)0.0192 (3)
C30.3247 (2)0.09640 (8)0.04316 (15)0.0205 (3)
C40.2676 (2)0.02663 (8)0.01250 (15)0.0204 (3)
C50.2523 (2)0.01136 (8)0.12259 (16)0.0230 (3)
H50.21540.03500.14240.028*
C60.2887 (2)0.06101 (8)0.23016 (15)0.0217 (3)
C20.3584 (2)0.14604 (8)0.06319 (15)0.0207 (3)
H20.39580.19220.04300.025*
C130.2253 (2)0.03137 (9)0.11877 (16)0.0261 (4)
C140.1717 (2)0.10595 (9)0.07708 (18)0.0298 (4)
H14C0.14490.13630.15650.045*
H14B0.07100.10170.03380.045*
H14A0.26530.12730.01450.045*
C100.3481 (2)0.18511 (9)0.44504 (16)0.0279 (4)
H10A0.43070.15030.49200.034*
H10B0.36530.23090.49400.034*
C110.3860 (2)0.19632 (8)0.29825 (16)0.0244 (4)
C70.2791 (2)0.03531 (9)0.37574 (16)0.0279 (4)
H70.39160.04620.43220.033*
C80.1391 (2)0.07785 (9)0.43676 (17)0.0294 (4)
H13A0.02690.06900.38050.035*
H13B0.13420.05860.52700.035*
C120.3533 (3)0.12064 (9)0.18269 (17)0.0296 (4)
H12C0.40060.16900.17700.044*
H12B0.24450.12030.24430.044*
H12A0.43320.08800.21560.044*
C90.1675 (2)0.15840 (9)0.44834 (17)0.0304 (4)
C150.2465 (3)0.04610 (9)0.38933 (18)0.0344 (4)
H15B0.13450.05830.33840.052*
H15A0.24950.05810.48380.052*
H15C0.33490.07310.35440.052*
C160.2815 (3)0.26390 (9)0.23925 (19)0.0398 (5)
H16A0.31210.27610.15230.060*
H16B0.30810.30420.30080.060*
H16C0.15930.25340.22800.060*
C170.5811 (3)0.21235 (11)0.3114 (2)0.0401 (5)
H17A0.64620.16940.34200.060*
H17B0.61210.25090.37620.060*
H17C0.60720.22680.22420.060*
O10.0495 (2)0.19936 (8)0.45978 (19)0.0569 (5)
O20.2338 (2)0.01978 (7)0.23812 (13)0.0451 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0204 (8)0.0162 (6)0.0213 (7)0.0013 (6)0.0047 (6)0.0012 (5)
C30.0206 (8)0.0216 (7)0.0201 (7)0.0008 (6)0.0053 (6)0.0008 (6)
C40.0216 (8)0.0197 (7)0.0206 (7)0.0009 (6)0.0056 (6)0.0023 (6)
C50.0305 (9)0.0162 (7)0.0246 (8)0.0016 (6)0.0110 (6)0.0008 (6)
C60.0284 (8)0.0181 (7)0.0207 (7)0.0003 (6)0.0100 (6)0.0007 (6)
C20.0233 (8)0.0158 (7)0.0240 (8)0.0002 (6)0.0065 (6)0.0019 (5)
C130.0299 (9)0.0236 (7)0.0255 (8)0.0000 (6)0.0065 (7)0.0034 (6)
C140.0380 (10)0.0216 (8)0.0309 (9)0.0030 (7)0.0088 (8)0.0075 (6)
C100.0407 (10)0.0212 (7)0.0209 (8)0.0002 (7)0.0023 (7)0.0041 (6)
C110.0336 (9)0.0166 (7)0.0231 (8)0.0007 (6)0.0056 (7)0.0023 (6)
C70.0406 (10)0.0226 (7)0.0227 (8)0.0006 (7)0.0118 (7)0.0004 (6)
C80.0383 (10)0.0308 (9)0.0215 (8)0.0040 (7)0.0118 (7)0.0031 (6)
C120.0415 (10)0.0265 (8)0.0225 (8)0.0031 (7)0.0104 (7)0.0019 (6)
C90.0420 (11)0.0297 (8)0.0218 (8)0.0067 (7)0.0115 (7)0.0022 (6)
C150.0477 (11)0.0278 (8)0.0305 (9)0.0021 (8)0.0150 (8)0.0045 (7)
C160.0705 (14)0.0206 (8)0.0293 (9)0.0125 (8)0.0109 (9)0.0009 (7)
C170.0399 (11)0.0412 (10)0.0392 (10)0.0167 (9)0.0065 (8)0.0103 (8)
O10.0600 (10)0.0397 (8)0.0797 (12)0.0175 (7)0.0368 (9)0.0021 (7)
O20.0778 (11)0.0364 (7)0.0217 (6)0.0148 (7)0.0099 (6)0.0065 (5)
Geometric parameters (Å, º) top
C1—C21.402 (2)C11—C171.534 (3)
C1—C61.412 (2)C11—C161.546 (2)
C1—C111.545 (2)C7—C151.527 (2)
C3—C21.387 (2)C7—C81.547 (2)
C3—C41.407 (2)C7—H70.9800
C3—C121.508 (2)C8—C91.498 (2)
C4—C51.396 (2)C8—H13A0.9700
C4—C131.498 (2)C8—H13B0.9700
C5—C61.398 (2)C12—H12C0.9600
C5—H50.9300C12—H12B0.9600
C6—C71.535 (2)C12—H12A0.9600
C2—H20.9300C9—O11.209 (2)
C13—O21.217 (2)C15—H15B0.9600
C13—C141.510 (2)C15—H15A0.9600
C14—H14C0.9600C15—H15C0.9600
C14—H14B0.9600C16—H16A0.9600
C14—H14A0.9600C16—H16B0.9600
C10—C91.497 (3)C16—H16C0.9600
C10—C111.549 (2)C17—H17A0.9600
C10—H10A0.9700C17—H17B0.9600
C10—H10B0.9700C17—H17C0.9600
C2—C1—C6117.47 (13)C15—C7—C6114.81 (13)
C2—C1—C11115.01 (12)C15—C7—C8108.73 (14)
C6—C1—C11127.49 (13)C6—C7—C8111.27 (13)
C2—C3—C4117.42 (13)C15—C7—H7107.2
C2—C3—C12117.90 (14)C6—C7—H7107.2
C4—C3—C12124.68 (14)C8—C7—H7107.2
C5—C4—C3118.18 (13)C9—C8—C7115.09 (14)
C5—C4—C13119.40 (13)C9—C8—H13A108.5
C3—C4—C13122.41 (13)C7—C8—H13A108.5
C4—C5—C6124.41 (14)C9—C8—H13B108.5
C4—C5—H5117.8C7—C8—H13B108.5
C6—C5—H5117.8H13A—C8—H13B107.5
C5—C6—C1117.48 (13)C3—C12—H12C109.5
C5—C6—C7118.96 (13)C3—C12—H12B109.5
C1—C6—C7123.50 (13)H12C—C12—H12B109.5
C3—C2—C1124.97 (14)C3—C12—H12A109.5
C3—C2—H2117.5H12C—C12—H12A109.5
C1—C2—H2117.5H12B—C12—H12A109.5
O2—C13—C4121.39 (15)O1—C9—C10122.13 (16)
O2—C13—C14119.23 (14)O1—C9—C8121.14 (18)
C4—C13—C14119.37 (14)C10—C9—C8116.73 (15)
C13—C14—H14C109.5C7—C15—H15B109.5
C13—C14—H14B109.5C7—C15—H15A109.5
H14C—C14—H14B109.5H15B—C15—H15A109.5
C13—C14—H14A109.5C7—C15—H15C109.5
H14C—C14—H14A109.5H15B—C15—H15C109.5
H14B—C14—H14A109.5H15A—C15—H15C109.5
C9—C10—C11113.10 (14)C11—C16—H16A109.5
C9—C10—H10A109.0C11—C16—H16B109.5
C11—C10—H10A109.0H16A—C16—H16B109.5
C9—C10—H10B109.0C11—C16—H16C109.5
C11—C10—H10B109.0H16A—C16—H16C109.5
H10A—C10—H10B107.8H16B—C16—H16C109.5
C17—C11—C1108.73 (13)C11—C17—H17A109.5
C17—C11—C16109.32 (15)C11—C17—H17B109.5
C1—C11—C16108.79 (14)H17A—C17—H17B109.5
C17—C11—C10106.74 (14)C11—C17—H17C109.5
C1—C11—C10116.12 (12)H17A—C17—H17C109.5
C16—C11—C10106.99 (13)H17B—C17—H17C109.5

Experimental details

Crystal data
Chemical formulaC17H22O2
Mr258.35
Crystal system, space groupMonoclinic, P21/n
Temperature (K)180
a, b, c (Å)7.7996 (6), 18.3702 (10), 9.9357 (6)
β (°) 99.616 (7)
V3)1403.59 (16)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.6 × 0.25 × 0.10
Data collection
DiffractometerOxford Diffraction Xcalibur Eos Gemini ultra
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
14554, 2855, 2196
Rint0.054
(sin θ/λ)max1)0.625
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.052, 0.145, 1.08
No. of reflections2855
No. of parameters177
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.61, 0.29

Computer programs: CrysAlis PRO (Oxford Diffraction, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

 

Acknowledgements

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.

References

First citationCremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354–1358.  CrossRef CAS Web of Science Google Scholar
First citationDaunis, J., Jaquier, R., Lopez, H. & Viallefont, Ph. (1981). J. Chem. Res. pp. 0639-0649  Google Scholar
First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
First citationFarrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838.  CrossRef CAS IUCr Journals Google Scholar
First citationLoughzail, M., Mazoir, N., Maya, C. M., Berraho, M., Benharref, A. & Bouhmaida, N. (2009). Acta Cryst. E65, o4.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationMazoir, N., El Ammari, L., Bouhmaida, N., Dahaoui, S., Benharref, A. & Berraho, M. (2009). Acta Cryst. E65, o1269–o1270.  Web of Science CSD CrossRef IUCr Journals Google Scholar
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First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSon Bredenberg, J. B. & Erdtman, H. (1961). Acta Chem. Scand. 15, 685–688  Google Scholar

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
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