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

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ISSN: 2056-9890
Volume 64| Part 9| September 2008| Pages m1122-m1123

Di-μ-bromido-bis­­[bromido(di-2-pyridylmethane­diol-κ2N,N′)copper(II)] dihydrate

aDepartment of Chemistry and Biochemistry, Central Connecticut State University, New Britain, CT 06050, USA, bRigaku Americas Corp., 9009 New Trails Dr., The Woodlands, TX 77381, USA, and cDepartment of Chemistry, Youngstown State University, Youngstown, OH 44555, USA
*Correspondence e-mail: westcottb@ccsu.edu

(Received 20 June 2008; accepted 29 July 2008; online 6 August 2008)

The centrosymmetric title complex, [Cu2Br4(C11H10N2O2)2]·2H2O, was one of three complexes isolated by slow evaporation of an acetonitrile reaction mixture of CuBr2 with di-2-pyridyl ketone (1:1 molar ratio). The title complex contains a 1:1 metal-to-ligand ratio of copper(II) with the hydrated form of the ligand di-2-pyridylmethane­diol. The copper centers are bridged by bromide donors, leading to a Cu—Cu distance of 4.090 (6) Å. The crystals form as non-merohedral twins with two components related by a 180° rotation around the normal to [100]; the selected sample had a twin ratio of 0.63:0.37.

Related literature

Apart from the title complex, two others were isolated from the reaction mixture and structurally characterized. One complex was reported previously by Parker et al. (2000[Parker, O. J., Aubol, S. L. & Breneman, G. L. (2000). Polyhedron, 19, 623-626.]), the other is reported in the preceding paper by Zeller et al. (2008[Zeller, M., Westcott, B. L., Kopp-Vaughn, K. M. & Hunter, A. D. (2008). Acta Cryst. E64, m1121.]). For other related structures, see: Wang et al. (1986[Wang, S.-L., Richardson, J. W. Jr, Briggs, S. J., Jacobson, R. A. & Jensen, W. P. (1986). Inorg. Chim. Acta, 111, 67-72.]); Mariezcurrena et al. (1999[Mariezcurrena, R. A., Mombrú, A. W., Suescun, L., Kremer, E. & González, R. (1999). Acta Cryst. C55, 1989-1991.]).

[Scheme 1]

Experimental

Crystal data
  • [Cu2Br4(C11H10N2O2)2]·2H2O

  • Mr = 887.18

  • Monoclinic, C 2/c

  • a = 21.2685 (7) Å

  • b = 9.1275 (3) Å

  • c = 14.4731 (4) Å

  • β = 100.749 (2)°

  • V = 2760.34 (15) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 7.38 mm−1

  • T = 100 (2) K

  • 0.34 × 0.25 × 0.13 mm

Data collection
  • Rigaku R-AXIS RAPID diffractometer

  • Absorption correction: multi-scan (TwinSolve; Rigaku/MSC, 2002[Rigaku/MSC (2002). TwinSolve. Rigaku/MSC, The Woodlands, Texas, USA.]) Tmin = 0.08, Tmax = 0.38

  • 46376 measured reflections

  • 7508 independent reflections

  • 6192 reflections with I > 2σ(I)

  • Rint = 0.058

Refinement
  • R[F2 > 2σ(F2)] = 0.065

  • wR(F2) = 0.198

  • S = 1.13

  • 7508 reflections

  • 185 parameters

  • 2 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 1.54 e Å−3

  • Δρmin = −1.58 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O3—H11⋯Br1i 0.85 (6) 2.53 (6) 3.361 (5) 166 (9)
O2—H9⋯O1ii 0.77 (6) 2.21 (7) 2.961 (7) 147 (9)
O2—H9⋯Br1ii 0.77 (6) 2.87 (9) 3.411 (5) 123 (8)
O3—H10⋯Br2 0.85 (6) 2.80 (8) 3.542 (6) 147 (9)
Symmetry codes: (i) [x, -y+1, z-{\script{1\over 2}}]; (ii) [-x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1].

Data collection: CrystalClear (Rigaku/MSC, 2004[Rigaku/MSC (2004). CrystalClear. Rigaku/MSC, The Woodlands, Texas, USA.]); cell refinement: TwinSolve (Rigaku/MSC, 2002[Rigaku/MSC (2002). TwinSolve. Rigaku/MSC, The Woodlands, Texas, USA.]); data reduction: TwinSolve; program(s) used to solve structure: SIR92 (Altomare et al., 1994[Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: CrystalStructure (Rigaku, 2006[Rigaku (2006). CrystalStructure. Rigaku Corporation, Tokyo, Japan.]); software used to prepare material for publication: publCIF (Westrip, 2008[Westrip, S. P. (2008). publCIF. In preparation.]).

Supporting information


Comment top

The title compound was one of three Cu–dpkoh complexes isolated from the 1:1 molar mixture of copper(II)bromide and di-2-pyridyl ketone, and was the third isolated from solution. The remaining two strutcures are described in Parker et al. (2000) and Zeller et al. (2008).

Related literature top

Apart from the title complex, two others were isolated from the reaction mixture and structurally characterized. One complex was reported previously by Parker et al. (2000), the other is reported by Zeller et al. (2008). For other related structures, see: Wang et al. (1986); Mariezcurrena et al. (1999).

Experimental top

Di-2-pyridyl ketone (dpk) was purchased from Aldrich and used as received. Copper(II) bromide hexahydrate was dried in an oven at 110°C for 48 h before use. DPK (1 mmol) and copper(II) bromide (1 mmol) were combined in 40 ml acetonitrile and stirred for 30 minutes. The resulting olive crystals were isolated after 5 days by slow evaporation of the solution. Prior to harvesting these crystals, crystals of two other distinct complexes were removed by gravity filtration.

Refinement top

The crystals form as non-merohedral twins. All reflections for both domains (44628 total) were integrated with the Rigaku TwinSolve program, to produce 3540 reflections for component 1 only, 3645 for component 2 only, and 815 containing contributions from both components (including systematic absences). The two twin components are related by a 180° rotation around the normal to [1 0 0], given by the matrix (1 0 0.549, 0 - 1 0, 0 0 - 1)

The positions of H atoms bonded to O were allowed to refine with isotropic displacement parameter set equal to the isotropic equivalent value for the attached atom. A mild restraint was applied to the two ligand O—H distances (0.84 Å). Other H atoms were used in calculated positions (C—H 0.95 Å) with isotropic displacement parameter set equal to 1.2 times the the isotropic equivalent value for the attached atom.

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2004); cell refinement: TwinSolve (Rigaku/MSC, 2002); data reduction: TwinSolve (Rigaku/MSC, 2002); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CrystalStructure (Rigaku, 2006); software used to prepare material for publication: publCIF (Westrip, 2008).

Figures top
[Figure 1] Fig. 1. ORTEP view of the unique part of the Cu complex, drawn with 60% probability displacement ellipsoids for the non-H atoms. The water molecule that loosely bridges Br atoms between adjacent complexes is not shown.
[Figure 2] Fig. 2. A view of the dimeric unit generated by the association of one of the Br ligands with the Cu atom of an adjacent molecule. The longer interactions of the Br and O atoms are shown as dashed lines. Non-H atoms are drawn with 60% probability ellipsoids.
Di-µ-bromido-bis[bromido(di-2-pyridylmethanediol-κ2N,N')copper(II)] dihydrate top
Crystal data top
[Cu2Br4(C11H10N2O2)2]·2H2OF(000) = 1720
Mr = 887.18Dx = 2.135 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 13358 reflections
a = 21.2685 (7) Åθ = 2.7–29.8°
b = 9.1275 (3) ŵ = 7.38 mm1
c = 14.4731 (4) ÅT = 100 K
β = 100.749 (2)°Blocks, green
V = 2760.34 (15) Å30.34 × 0.25 × 0.13 mm
Z = 4
Data collection top
Rigaku R-AXIS RAPID
diffractometer
7508 independent reflections
Radiation source: fine-focus sealed tube6192 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.058
Detector resolution: 10 pixels mm-1θmax = 30.1°, θmin = 2.7°
ω scansh = 2929
Absorption correction: multi-scan
(TwinSolve; Rigaku/MSC, 2002)
k = 1212
Tmin = 0.08, Tmax = 0.38l = 2020
46376 measured 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)] = 0.065Hydrogen site location: difference Fourier map
wR(F2) = 0.198H atoms treated by a mixture of independent and constrained refinement
S = 1.13 w = 1/[σ2(Fo2) + (0.0753P)2 + 82.8356P]
where P = (Fo2 + 2Fc2)/3
7508 reflections(Δ/σ)max = 0.002
185 parametersΔρmax = 1.54 e Å3
2 restraintsΔρmin = 1.58 e Å3
Crystal data top
[Cu2Br4(C11H10N2O2)2]·2H2OV = 2760.34 (15) Å3
Mr = 887.18Z = 4
Monoclinic, C2/cMo Kα radiation
a = 21.2685 (7) ŵ = 7.38 mm1
b = 9.1275 (3) ÅT = 100 K
c = 14.4731 (4) Å0.34 × 0.25 × 0.13 mm
β = 100.749 (2)°
Data collection top
Rigaku R-AXIS RAPID
diffractometer
7508 independent reflections
Absorption correction: multi-scan
(TwinSolve; Rigaku/MSC, 2002)
6192 reflections with I > 2σ(I)
Tmin = 0.08, Tmax = 0.38Rint = 0.058
46376 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0652 restraints
wR(F2) = 0.198H atoms treated by a mixture of independent and constrained refinement
S = 1.13 w = 1/[σ2(Fo2) + (0.0753P)2 + 82.8356P]
where P = (Fo2 + 2Fc2)/3
7508 reflectionsΔρmax = 1.54 e Å3
185 parametersΔρmin = 1.58 e Å3
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
Br10.15441 (3)0.62635 (7)0.55691 (4)0.01359 (14)
Br20.02135 (3)0.54295 (7)0.38142 (4)0.01492 (15)
Cu10.08934 (3)0.41245 (8)0.50766 (5)0.00990 (16)
O10.1794 (2)0.2937 (5)0.4473 (3)0.0137 (8)
H120.165 (4)0.306 (9)0.394 (3)0.014*
O20.2056 (2)0.0447 (5)0.4596 (4)0.0163 (9)
H90.241 (2)0.052 (10)0.484 (6)0.016*
O30.1174 (2)0.3109 (6)0.2691 (4)0.0216 (10)
H100.091 (5)0.391 (10)0.270 (6)0.022*
H110.126 (4)0.334 (10)0.215 (7)0.022*
N10.1400 (2)0.2914 (6)0.6142 (4)0.0121 (9)
N20.0544 (2)0.2175 (6)0.4509 (4)0.0107 (9)
C10.1432 (3)0.3159 (8)0.7059 (5)0.0199 (14)
H10.12100.39570.72380.024*
C20.1773 (3)0.2300 (8)0.7748 (5)0.0208 (14)
H20.17920.25280.83790.025*
C30.2088 (3)0.1091 (9)0.7493 (5)0.0231 (15)
H30.23200.04860.79510.028*
C40.2058 (3)0.0783 (8)0.6545 (5)0.0168 (12)
H40.22560.00450.63560.020*
C50.1724 (3)0.1751 (7)0.5888 (4)0.0134 (11)
C60.1666 (3)0.1538 (7)0.4830 (4)0.0103 (10)
C70.0974 (3)0.1111 (6)0.4443 (4)0.0106 (10)
C80.0795 (3)0.0259 (7)0.4077 (4)0.0139 (11)
H50.10980.09900.40650.017*
C90.0145 (3)0.0511 (7)0.3725 (4)0.0146 (11)
H60.00100.14150.34650.017*
C100.0295 (3)0.0584 (7)0.3766 (4)0.0149 (12)
H70.07270.04380.35220.018*
C110.0078 (3)0.1923 (7)0.4184 (5)0.0137 (11)
H80.03740.26540.42370.016*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0089 (2)0.0146 (3)0.0168 (3)0.0002 (2)0.0011 (2)0.0018 (2)
Br20.0159 (3)0.0139 (3)0.0133 (3)0.0015 (2)0.0015 (2)0.0027 (2)
Cu10.0087 (3)0.0108 (3)0.0095 (3)0.0007 (2)0.0003 (2)0.0002 (3)
O10.012 (2)0.020 (2)0.0103 (19)0.0023 (17)0.0046 (16)0.0041 (17)
O20.0081 (19)0.018 (2)0.023 (2)0.0049 (17)0.0022 (17)0.0022 (18)
O30.019 (2)0.033 (3)0.013 (2)0.002 (2)0.0031 (18)0.008 (2)
N10.007 (2)0.017 (2)0.011 (2)0.0003 (18)0.0015 (17)0.0040 (19)
N20.010 (2)0.011 (2)0.011 (2)0.0045 (18)0.0031 (17)0.0051 (18)
C10.020 (3)0.028 (4)0.013 (3)0.007 (3)0.007 (2)0.009 (3)
C20.020 (3)0.032 (4)0.010 (3)0.009 (3)0.001 (2)0.001 (3)
C30.012 (3)0.039 (4)0.018 (3)0.003 (3)0.001 (2)0.018 (3)
C40.007 (2)0.024 (3)0.019 (3)0.001 (2)0.001 (2)0.009 (3)
C50.009 (2)0.018 (3)0.012 (3)0.001 (2)0.001 (2)0.000 (2)
C60.003 (2)0.013 (3)0.014 (3)0.0023 (19)0.0003 (19)0.001 (2)
C70.012 (3)0.010 (3)0.010 (2)0.003 (2)0.004 (2)0.003 (2)
C80.014 (3)0.013 (3)0.016 (3)0.004 (2)0.006 (2)0.002 (2)
C90.014 (3)0.015 (3)0.014 (3)0.001 (2)0.000 (2)0.000 (2)
C100.010 (3)0.019 (3)0.015 (3)0.005 (2)0.000 (2)0.004 (2)
C110.011 (3)0.012 (3)0.017 (3)0.003 (2)0.000 (2)0.005 (2)
Geometric parameters (Å, º) top
Br1—Cu12.4222 (10)C2—C31.377 (11)
Br2—Cu12.4212 (9)C2—H20.9300
Cu1—N12.034 (5)C3—C41.390 (10)
Cu1—N22.041 (5)C3—H30.9300
Cu1—Br2i3.1138 (10)C4—C51.392 (9)
O1—C61.423 (7)C4—H40.9300
O1—H120.78 (4)C5—C61.527 (8)
O2—C61.378 (7)C6—C71.525 (8)
O2—H90.77 (4)C7—C81.382 (9)
O3—H100.92 (10)C8—C91.402 (9)
O3—H110.86 (10)C8—H50.9300
N1—C11.335 (8)C9—C101.377 (9)
N1—C51.353 (8)C9—H60.9300
N2—C111.339 (8)C10—C111.403 (9)
N2—C71.349 (7)C10—H70.9300
C1—C21.367 (10)C11—H80.9300
C1—H10.9300
N1—Cu1—N286.2 (2)C3—C4—C5118.0 (7)
N1—Cu1—Br2175.12 (15)C3—C4—H4121.0
N2—Cu1—Br290.21 (14)C5—C4—H4121.0
N1—Cu1—Br191.25 (15)N1—C5—C4122.3 (6)
N2—Cu1—Br1165.08 (15)N1—C5—C6115.0 (5)
Br2—Cu1—Br193.07 (3)C4—C5—C6122.7 (6)
N1—Cu1—Br2i91.44 (15)O2—C6—O1113.3 (5)
N2—Cu1—Br2i93.91 (15)O2—C6—C7108.0 (5)
Br2—Cu1—Br2i85.54 (3)O1—C6—C7109.5 (4)
Br1—Cu1—Br2i100.85 (3)O2—C6—C5113.5 (5)
C6—O1—H12114 (6)O1—C6—C5105.3 (5)
C6—O2—H9114 (7)C7—C6—C5107.1 (5)
H10—O3—H1193 (8)N2—C7—C8122.5 (6)
C1—N1—C5117.9 (6)N2—C7—C6114.2 (5)
C1—N1—Cu1125.7 (5)C8—C7—C6123.3 (5)
C5—N1—Cu1116.5 (4)C7—C8—C9118.0 (6)
C11—N2—C7119.3 (5)C7—C8—H5121.0
C11—N2—Cu1123.6 (4)C9—C8—H5121.0
C7—N2—Cu1117.1 (4)C10—C9—C8119.9 (6)
N1—C1—C2123.4 (7)C10—C9—H6120.1
N1—C1—H1118.3C8—C9—H6120.1
C2—C1—H1118.3C9—C10—C11118.6 (6)
C1—C2—C3119.0 (6)C9—C10—H7120.7
C1—C2—H2120.5C11—C10—H7120.7
C3—C2—H2120.5N2—C11—C10121.7 (6)
C2—C3—C4119.4 (6)N2—C11—H8119.2
C2—C3—H3120.3C10—C11—H8119.2
C4—C3—H3120.3
N2—Cu1—N1—C1131.0 (6)C4—C5—C6—O210.3 (9)
Br1—Cu1—N1—C163.9 (5)N1—C5—C6—O149.0 (7)
N2—Cu1—N1—C547.9 (5)C4—C5—C6—O1134.4 (6)
Br1—Cu1—N1—C5117.3 (4)N1—C5—C6—C767.6 (7)
N1—Cu1—N2—C11131.8 (6)C4—C5—C6—C7109.0 (7)
Br1—Cu1—N2—C11147.0 (5)C11—N2—C7—C81.5 (9)
Br2—Cu1—N2—C1144.9 (5)Cu1—N2—C7—C8179.3 (5)
N1—Cu1—N2—C749.1 (5)C11—N2—C7—C6179.7 (6)
Br2—Cu1—N2—C7134.2 (4)Cu1—N2—C7—C60.6 (7)
C5—N1—C1—C20.3 (10)O2—C6—C7—N2171.3 (5)
Cu1—N1—C1—C2179.1 (5)O1—C6—C7—N247.5 (7)
N1—C1—C2—C32.1 (11)C5—C6—C7—N266.6 (7)
C1—C2—C3—C40.8 (11)O2—C6—C7—C810.0 (8)
C2—C3—C4—C52.2 (10)O1—C6—C7—C8133.8 (6)
C1—N1—C5—C42.9 (9)C5—C6—C7—C8112.1 (7)
Cu1—N1—C5—C4176.0 (5)N2—C7—C8—C93.0 (9)
C1—N1—C5—C6179.6 (6)C6—C7—C8—C9178.4 (6)
Cu1—N1—C5—C60.6 (7)C7—C8—C9—C102.0 (10)
C3—C4—C5—N14.2 (10)C7—N2—C11—C101.0 (10)
C3—C4—C5—C6179.4 (6)C9—C10—C11—N21.9 (10)
N1—C5—C6—O2173.1 (5)
Symmetry code: (i) x, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H11···Br1ii0.85 (6)2.53 (6)3.361 (5)166 (9)
O2—H9···O1iii0.77 (6)2.21 (7)2.961 (7)147 (9)
O2—H9···Br1iii0.77 (6)2.87 (9)3.411 (5)123 (8)
O3—H10···Br20.85 (6)2.80 (8)3.542 (6)147 (9)
Symmetry codes: (ii) x, y+1, z1/2; (iii) x+1/2, y+1/2, z+1.

Experimental details

Crystal data
Chemical formula[Cu2Br4(C11H10N2O2)2]·2H2O
Mr887.18
Crystal system, space groupMonoclinic, C2/c
Temperature (K)100
a, b, c (Å)21.2685 (7), 9.1275 (3), 14.4731 (4)
β (°) 100.749 (2)
V3)2760.34 (15)
Z4
Radiation typeMo Kα
µ (mm1)7.38
Crystal size (mm)0.34 × 0.25 × 0.13
Data collection
DiffractometerRigaku R-AXIS RAPID
diffractometer
Absorption correctionMulti-scan
(TwinSolve; Rigaku/MSC, 2002)
Tmin, Tmax0.08, 0.38
No. of measured, independent and
observed [I > 2σ(I)] reflections
46376, 7508, 6192
Rint0.058
(sin θ/λ)max1)0.705
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.065, 0.198, 1.13
No. of reflections7508
No. of parameters185
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
w = 1/[σ2(Fo2) + (0.0753P)2 + 82.8356P]
where P = (Fo2 + 2Fc2)/3
Δρmax, Δρmin (e Å3)1.54, 1.58

Computer programs: CrystalClear (Rigaku/MSC, 2004), TwinSolve (Rigaku/MSC, 2002), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008), CrystalStructure (Rigaku, 2006), publCIF (Westrip, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H11···Br1i0.85 (6)2.53 (6)3.361 (5)166 (9)
O2—H9···O1ii0.77 (6)2.21 (7)2.961 (7)147 (9)
O2—H9···Br1ii0.77 (6)2.87 (9)3.411 (5)123 (8)
O3—H10···Br20.85 (6)2.80 (8)3.542 (6)147 (9)
Symmetry codes: (i) x, y+1, z1/2; (ii) x+1/2, y+1/2, z+1.
 

Acknowledgements

The authors thank Dr Guy Crundwell (CCSU) for helpful discussions. BLW acknowledges funding from the National Science Foundation (NSF #0420322). MZ acknowledge funding from the National Science Foundation (NSF #0087210) and the Ohio Board of Regents (CAP-491).

References

First citationAltomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.  CrossRef Web of Science IUCr Journals Google Scholar
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Volume 64| Part 9| September 2008| Pages m1122-m1123
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