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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 5| May 2011| Page o1044

Ethyl (2E)-2-(2H-1,3-benzodioxol-5-yl­methyl­­idene)-4-chloro-3-oxo­butano­ate

aDepartment of Chemistry, Universidade Federal de São Carlos, 13565-905 São Carlos, SP, Brazil, bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, and cInstituto de Química, Universidade Estadual de Campinas, CP 6154, 13083-970 Campinas, SP, Brazil
*Correspondence e-mail: julio@power.ufscar.br

(Received 26 March 2011; accepted 30 March 2011; online 7 April 2011)

In the title compound, C14H13ClO5, the five-membered ring is in an envelope conformation with the methyl­ene C-atom being the flap. The conformation about the C=C double bond [1.341 (2) Å] is E. The chloro­propan-2-one residue is approximately orthogonal to the remaining mol­ecule [dihedral angle = 88.03 (6)°]. In the crystal, the mol­ecules associate via C—H⋯O inter­actions, involving both carbonyl-O atoms, giving rise to an undulating two-dimensional array in the ac plane.

Related literature

For background to the study, see: Rodrigues et al. (2004[Rodrigues, J. A. R., Moran, P. J. S., Conceicão, G. J. A. & Fardelone, L. C. (2004). Food Technol. Biotechnol. 42, 295-303.]). For ring conformational analysis, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C14H13ClO5

  • Mr = 296.69

  • Orthorhombic, P 21 21 21

  • a = 4.8042 (1) Å

  • b = 14.9134 (4) Å

  • c = 18.4793 (5) Å

  • V = 1323.99 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.31 mm−1

  • T = 100 K

  • 0.28 × 0.07 × 0.06 mm

Data collection
  • Bruker SMART APEX diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.636, Tmax = 0.746

  • 13030 measured reflections

  • 3200 independent reflections

  • 2915 reflections with I > 2σ(I)

  • Rint = 0.041

Refinement
  • R[F2 > 2σ(F2)] = 0.031

  • wR(F2) = 0.073

  • S = 1.05

  • 3200 reflections

  • 182 parameters

  • H-atom parameters constrained

  • Δρmax = 0.28 e Å−3

  • Δρmin = −0.18 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1312 Friedel pairs

  • Flack parameter: −0.03 (5)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C1—H1a⋯O4i 0.97 2.50 3.348 (2) 146
C11—H11b⋯O3ii 0.97 2.36 3.1585 (18) 139
Symmetry codes: (i) [-x+{\script{3\over 2}}, -y, z+{\script{1\over 2}}]; (ii) x+1, y, z.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SIR97 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); 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 DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: Marvin­Sketch (Chemaxon, 2010[Chemaxon (2010). Marvinsketch. http://www.chemaxon.com]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

As part of the continuing interest in the bio-reduction of α-haloketones and enones (Rodrigues et al., 2004) the title compound, ethyl (2E)-2-(2H-1,3-benzodioxol-5-ylmethylidene)-4- chloro-3-oxobutanoate, (I), was synthesized by means of a Knoevenagel condensation reaction between ethyl 4-chloroacetoacetate and piperonal, affording a mixture of E and Z isomers that were separated by column chromatography (hexane/ethyl acetate, gradient from pure hexane to 95% hexane/5% ethyl acetate).

The conformation of the five-membered ring in (I) is an envelope with the methylene-C1 atom being the flap. This is quantified by the ring puckering parameters Q(2) = 0.1016 (14) Å and ϕ2 = 38.4 (8) ° (Cremer & Pople, 1975). The conformation about the C8C9 double bond [1.341 (2) Å] is E. With the exception of the chloropropan-2-one residue which projects to one side of the molecule, (I) is approximately flat. The major twist in the molecule occurs around the C5—C8 bond as seen in the value of the C4—C5—C8—C9 torsion angle of 165.21 (16) °. The carbonyl and chlorido atoms of the chloropropan-2-one residue lie in a plane with the C3 backbone. This plane is orthogonal to the main residue with the dihedral angle between the least-squares plane through the O3,C9—C11,Cl1 atoms and that through the C8,C9,C12 atoms being 88.03 (6) °. Both heteroatoms project away from the main residue.

The two most prominent interactions operating in the crystal structure are of the type C—H···O, Table 1. The shortest interaction occurs between symmetry related carbonyl-O and methylene-H atoms of the chloropropan-2-one residues leading to a chain along the a direction. The other C—H···O interaction occurs between the ester-carbonyl-O and the methylene-H of the benzodioxole residue. Overall, the resulting supramolecular architecture is a 2-D array in the ac plane, Fig. 2. The topology is undulating as seen from Fig. 3.

Related literature top

For background to the study, see: Rodrigues et al. (2004). For ring conformational analysis, see: Cremer & Pople (1975).

Experimental top

The title compound, (I), was prepared by means of a Knoevenagel condensation reaction between ethyl 4-chloroacetoacetate and piperonal. Morpholine (17.4 mg, 0.2 mmol), glacial acetic acid (12.0 mg, 0.2 mmol) and piperonal (300 mg, 2 mmol) were added to [Bmim][NTf2] (1 ml) in a 10 ml round-bottom flask. The mixture was stirred for 10 min., and then ethyl 4-chloroacetoacetate (395 mg, 2.4 mmol) and 4 Å molecular sieves (360 mg) were added to reaction mixture. After 1.5 h, the ionic liquid layer was extracted with diethyl ether (3 x 5 ml), the ether was evaporated to afford a mixture of E and Z isomers that were separated by column chromatography (hexane/ethyl acetate, gradient from pure hexane to 95% hexane/5% ethyl acetate). The crystallized isomer, obtained by slow evaporation from a dichloromethane/hexane mixture, was shown by crystallography to be the E isomer; M.pt. 367.1–367.4 K.

Refinement top

Carbon-bound H-atoms were placed in calculated positions (C—H 0.93 to 0.97 Å) and were included in the refinement in the riding model approximation, with Uiso(H) = 1.2Ueq(C) and 1.5Ueq(methyl-C).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: MarvinSketch (Chemaxon, 2010) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of compound (I) showing the atom-labelling scheme and displacement ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. view of the supramolecular layer in (I) mediated by C—H···O interactions (blue dashed lines).
[Figure 3] Fig. 3. A view in projection down the a axis of the unit-cell contents for (I). The view highlights the undulating topology for the layer shown in Fig. 2, with one layer emphasized in space flling mode. The C—H···O interactions are shown as blue dashed lines.
Ethyl (2E)-2-(2H-1,3-benzodioxol-5-ylmethylidene)-4-chloro-3- oxobutanoate top
Crystal data top
C14H13ClO5F(000) = 616
Mr = 296.69Dx = 1.488 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 4024 reflections
a = 4.8042 (1) Åθ = 2.6–28.6°
b = 14.9134 (4) ŵ = 0.31 mm1
c = 18.4793 (5) ÅT = 100 K
V = 1323.99 (6) Å3Needle, colourless
Z = 40.28 × 0.07 × 0.06 mm
Data collection top
Bruker SMART APEX
diffractometer
3200 independent reflections
Radiation source: fine-focus sealed tube2915 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.041
ω scanθmax = 28.0°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 66
Tmin = 0.636, Tmax = 0.746k = 1919
13030 measured reflectionsl = 2424
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)] = 0.031H-atom parameters constrained
wR(F2) = 0.073 w = 1/[σ2(Fo2) + (0.0415P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max < 0.001
3200 reflectionsΔρmax = 0.28 e Å3
182 parametersΔρmin = 0.18 e Å3
0 restraintsAbsolute structure: Flack (1983), 1312 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.03 (5)
Crystal data top
C14H13ClO5V = 1323.99 (6) Å3
Mr = 296.69Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 4.8042 (1) ŵ = 0.31 mm1
b = 14.9134 (4) ÅT = 100 K
c = 18.4793 (5) Å0.28 × 0.07 × 0.06 mm
Data collection top
Bruker SMART APEX
diffractometer
3200 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2915 reflections with I > 2σ(I)
Tmin = 0.636, Tmax = 0.746Rint = 0.041
13030 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.031H-atom parameters constrained
wR(F2) = 0.073Δρmax = 0.28 e Å3
S = 1.05Δρmin = 0.18 e Å3
3200 reflectionsAbsolute structure: Flack (1983), 1312 Friedel pairs
182 parametersAbsolute structure parameter: 0.03 (5)
0 restraints
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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
Cl0.61259 (8)0.13689 (2)0.67747 (2)0.02387 (11)
O10.3303 (2)0.08014 (8)1.03191 (6)0.0210 (3)
O20.1425 (2)0.01153 (7)0.93013 (5)0.0176 (2)
O30.3855 (2)0.04539 (7)0.66362 (5)0.0184 (2)
O40.8831 (2)0.13250 (7)0.57678 (5)0.0175 (2)
O51.0712 (2)0.23928 (7)0.64786 (5)0.0166 (2)
C10.1462 (4)0.00951 (11)1.00813 (8)0.0184 (3)
H1A0.21280.04821.02510.022*
H1B0.03970.01911.02710.022*
C20.4641 (3)0.10950 (10)0.97104 (8)0.0146 (3)
C30.6715 (3)0.17232 (10)0.96631 (8)0.0167 (3)
H30.74410.20011.00720.020*
C40.7684 (3)0.19244 (10)0.89674 (8)0.0154 (3)
H40.90670.23560.89140.018*
C50.6645 (3)0.14994 (9)0.83495 (8)0.0132 (3)
C60.4459 (3)0.08662 (10)0.84196 (8)0.0148 (3)
H60.36880.05870.80170.018*
C70.3532 (3)0.06826 (9)0.91020 (8)0.0140 (3)
C80.7904 (3)0.17377 (10)0.76594 (8)0.0144 (3)
H80.89860.22550.76660.017*
C90.7744 (3)0.13267 (10)0.70152 (8)0.0136 (3)
C100.6222 (3)0.04657 (10)0.68599 (7)0.0135 (3)
C110.7940 (3)0.03659 (10)0.69812 (9)0.0177 (3)
H11A0.85270.03840.74830.021*
H11B0.96000.03330.66840.021*
C120.9143 (3)0.16725 (10)0.63571 (8)0.0136 (3)
C131.2296 (4)0.27097 (11)0.58593 (9)0.0214 (4)
H13A1.10490.28860.54720.026*
H13B1.35090.22390.56810.026*
C141.3985 (4)0.34985 (11)0.61063 (9)0.0251 (4)
H14A1.27610.39690.62630.038*
H14B1.51120.37110.57130.038*
H14C1.51620.33210.65010.038*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl0.0263 (2)0.01483 (17)0.0305 (2)0.00619 (17)0.00241 (18)0.00049 (16)
O10.0265 (6)0.0228 (6)0.0136 (5)0.0044 (5)0.0053 (5)0.0004 (5)
O20.0181 (6)0.0201 (5)0.0146 (5)0.0027 (5)0.0027 (5)0.0025 (4)
O30.0143 (5)0.0232 (5)0.0177 (5)0.0013 (5)0.0021 (5)0.0022 (4)
O40.0194 (5)0.0206 (5)0.0126 (5)0.0016 (5)0.0009 (5)0.0006 (4)
O50.0197 (6)0.0172 (5)0.0128 (5)0.0048 (5)0.0045 (4)0.0007 (4)
C10.0193 (8)0.0211 (8)0.0147 (7)0.0004 (7)0.0024 (6)0.0040 (6)
C20.0179 (7)0.0152 (7)0.0108 (7)0.0060 (6)0.0035 (6)0.0005 (6)
C30.0208 (8)0.0169 (7)0.0125 (7)0.0019 (6)0.0018 (6)0.0029 (6)
C40.0171 (7)0.0112 (7)0.0179 (8)0.0002 (6)0.0016 (6)0.0013 (6)
C50.0149 (7)0.0121 (7)0.0125 (7)0.0025 (6)0.0010 (6)0.0008 (5)
C60.0158 (7)0.0150 (7)0.0137 (7)0.0007 (6)0.0012 (6)0.0013 (6)
C70.0108 (7)0.0120 (6)0.0192 (7)0.0013 (6)0.0009 (6)0.0006 (6)
C80.0134 (7)0.0126 (7)0.0172 (8)0.0001 (6)0.0009 (6)0.0012 (6)
C90.0115 (6)0.0148 (7)0.0144 (7)0.0007 (6)0.0010 (5)0.0021 (6)
C100.0156 (7)0.0178 (7)0.0071 (6)0.0018 (6)0.0027 (6)0.0010 (5)
C110.0166 (7)0.0141 (7)0.0223 (8)0.0041 (6)0.0032 (6)0.0000 (6)
C120.0113 (7)0.0141 (7)0.0154 (7)0.0025 (6)0.0004 (6)0.0003 (6)
C130.0252 (9)0.0238 (8)0.0153 (8)0.0066 (7)0.0058 (7)0.0015 (7)
C140.0304 (9)0.0235 (8)0.0214 (8)0.0107 (8)0.0035 (8)0.0023 (7)
Geometric parameters (Å, º) top
Cl—C111.7728 (15)C5—C61.418 (2)
O1—C21.3674 (18)C5—C81.456 (2)
O1—C11.4440 (19)C6—C71.365 (2)
O2—C71.3698 (18)C6—H60.9300
O2—C11.4417 (18)C8—C91.341 (2)
O3—C101.2100 (19)C8—H80.9300
O4—C121.2153 (18)C9—C121.482 (2)
O5—C121.3316 (18)C9—C101.505 (2)
O5—C131.4533 (18)C10—C111.507 (2)
C1—H1A0.9700C11—H11A0.9700
C1—H1B0.9700C11—H11B0.9700
C2—C31.370 (2)C13—C141.500 (2)
C2—C71.388 (2)C13—H13A0.9700
C3—C41.400 (2)C13—H13B0.9700
C3—H30.9300C14—H14A0.9600
C4—C51.398 (2)C14—H14B0.9600
C4—H40.9300C14—H14C0.9600
C2—O1—C1105.73 (11)C5—C8—H8115.0
C7—O2—C1105.82 (12)C8—C9—C12122.92 (14)
C12—O5—C13115.22 (11)C8—C9—C10125.93 (14)
O2—C1—O1107.25 (12)C12—C9—C10111.14 (12)
O2—C1—H1A110.3O3—C10—C9122.29 (14)
O1—C1—H1A110.3O3—C10—C11123.62 (14)
O2—C1—H1B110.3C9—C10—C11114.05 (12)
O1—C1—H1B110.3C10—C11—Cl113.15 (11)
H1A—C1—H1B108.5C10—C11—H11A108.9
O1—C2—C3127.81 (14)Cl—C11—H11A108.9
O1—C2—C7110.13 (13)C10—C11—H11B108.9
C3—C2—C7122.03 (14)Cl—C11—H11B108.9
C2—C3—C4116.55 (14)H11A—C11—H11B107.8
C2—C3—H3121.7O4—C12—O5124.39 (14)
C4—C3—H3121.7O4—C12—C9122.08 (14)
C5—C4—C3122.29 (14)O5—C12—C9113.52 (12)
C5—C4—H4118.9O5—C13—C14107.37 (13)
C3—C4—H4118.9O5—C13—H13A110.2
C4—C5—C6119.44 (13)C14—C13—H13A110.2
C4—C5—C8117.17 (14)O5—C13—H13B110.2
C6—C5—C8123.38 (13)C14—C13—H13B110.2
C7—C6—C5117.36 (13)H13A—C13—H13B108.5
C7—C6—H6121.3C13—C14—H14A109.5
C5—C6—H6121.3C13—C14—H14B109.5
C6—C7—O2127.85 (14)H14A—C14—H14B109.5
C6—C7—C2122.28 (14)C13—C14—H14C109.5
O2—C7—C2109.85 (13)H14A—C14—H14C109.5
C9—C8—C5129.98 (14)H14B—C14—H14C109.5
C9—C8—H8115.0
C7—O2—C1—O110.89 (16)C3—C2—C7—O2177.48 (13)
C2—O1—C1—O210.58 (16)C4—C5—C8—C9165.21 (16)
C1—O1—C2—C3175.80 (15)C6—C5—C8—C914.7 (3)
C1—O1—C2—C76.33 (16)C5—C8—C9—C12179.08 (14)
O1—C2—C3—C4178.16 (14)C5—C8—C9—C102.2 (3)
C7—C2—C3—C40.5 (2)C8—C9—C10—O394.20 (19)
C2—C3—C4—C51.2 (2)C12—C9—C10—O386.95 (16)
C3—C4—C5—C62.5 (2)C8—C9—C10—C1187.96 (19)
C3—C4—C5—C8177.38 (14)C12—C9—C10—C1190.88 (15)
C4—C5—C6—C72.0 (2)O3—C10—C11—Cl0.83 (19)
C8—C5—C6—C7177.84 (14)C9—C10—C11—Cl178.63 (10)
C5—C6—C7—O2178.49 (13)C13—O5—C12—O45.4 (2)
C5—C6—C7—C20.4 (2)C13—O5—C12—C9175.26 (13)
C1—O2—C7—C6174.55 (15)C8—C9—C12—O4175.13 (15)
C1—O2—C7—C27.17 (16)C10—C9—C12—O46.0 (2)
O1—C2—C7—C6178.93 (14)C8—C9—C12—O54.2 (2)
C3—C2—C7—C60.9 (2)C10—C9—C12—O5174.69 (12)
O1—C2—C7—O20.53 (17)C12—O5—C13—C14178.22 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1a···O4i0.972.503.348 (2)146
C11—H11b···O3ii0.972.363.1585 (18)139
Symmetry codes: (i) x+3/2, y, z+1/2; (ii) x+1, y, z.

Experimental details

Crystal data
Chemical formulaC14H13ClO5
Mr296.69
Crystal system, space groupOrthorhombic, P212121
Temperature (K)100
a, b, c (Å)4.8042 (1), 14.9134 (4), 18.4793 (5)
V3)1323.99 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.31
Crystal size (mm)0.28 × 0.07 × 0.06
Data collection
DiffractometerBruker SMART APEX
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.636, 0.746
No. of measured, independent and
observed [I > 2σ(I)] reflections
13030, 3200, 2915
Rint0.041
(sin θ/λ)max1)0.660
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.031, 0.073, 1.05
No. of reflections3200
No. of parameters182
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.28, 0.18
Absolute structureFlack (1983), 1312 Friedel pairs
Absolute structure parameter0.03 (5)

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006), MarvinSketch (Chemaxon, 2010) and publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1a···O4i0.972.503.348 (2)146
C11—H11b···O3ii0.972.363.1585 (18)139
Symmetry codes: (i) x+3/2, y, z+1/2; (ii) x+1, y, z.
 

Acknowledgements

We thank the Brazilian agencies CNPq (306532/2009–3,to JZ-S), CAPES and FAPESP for financial support. The University of Malaya is thanked for support of the crystallographic facility.

References

First citationAltomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115–119.  Web of Science CrossRef CAS IUCr Journals Google Scholar
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Volume 67| Part 5| May 2011| Page o1044
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