[N,N′-Bis(2,6-diethyl-4-phenyl­phen­yl)butane-2,3-di­imine-κ2N,N′]di­bromido­nickel(II)

Yuan, J.; Xia, J.; Xu, W.; Mu, Y.

doi:10.1107/S160053681400292X

metal-organic compounds

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ISSN: 2056-9890

Volume 70| Part 3| March 2014| Page m102

doi:10.1107/S160053681400292X

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[N,N′-Bis(2,6-diethyl-4-phenylphenyl)butane-2,3-diimine-κ²N,N′]dibromidonickel(II)

Jianchao Yuan,^a ^* Jingjing Xia,^a Weibing Xu ^a and Yanqiong Mu ^a

^aKey Laboratory of Eco-Environment-Related Polymer Materials of Ministry of, Education, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou 730070, People's Republic of China
^*Correspondence e-mail: xjzlz1988@163.com

(Received 18 January 2014; accepted 9 February 2014; online 15 February 2014)

The complex molecule in the title compound, [NiBr₂(C₃₆H₄₀N₂)], has mirror symmetry. The Ni^II atom and two Br atoms are located on the mirror plane. The Ni^II atom is four-coordinated by the two Br atoms and two N atoms from an N,N′-bis(2,6-diethyl-4-phenylphenyl)butane-2,3-diimine ligand in a distorted tetrahedral geometry. The dihedral angle formed between the two adjacent benzene rings is 47.1 (1)°.

CCDC reference: 982220

Related literature

For background to α-diimine nickel catalysts, see: Johnson et al. (1995 ); Killian et al. (1996 ). For the effect of ligand structure on the reactivity of organometallic complexes, see: Popeney & Guan (2010 ); Popeney et al. (2011 ).

Experimental

Crystal data

[NiBr₂(C₃₆H₄₀N₂)]
M_r = 719.19
Orthorhombic, P n a m
a = 15.6587 (5) Å
b = 6.9359 (3) Å
c = 30.1928 (16) Å
V = 3279.2 (2) Å³
Z = 4
Mo Kα radiation
μ = 3.06 mm⁻¹
T = 293 K
0.42 × 0.38 × 0.35 mm

Data collection

Oxford Diffraction SuperNova CCD diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2012 $[Oxford Diffraction (2012). CrysAlis PRO. Agilent Technologies, Yarnton, England.]$ ) T_min = 0.508, T_max = 1.000
10334 measured reflections
3415 independent reflections
2376 reflections with I > 2σ(I)
R_int = 0.046

Refinement

R[F² > 2σ(F²)] = 0.043
wR(F²) = 0.096
S = 1.02
3415 reflections
193 parameters
H-atom parameters constrained
Δρ_max = 0.53 e Å⁻³
Δρ_min = −0.53 e Å⁻³

Table 1
Selected bond lengths (Å)

Ni1—N1	1.991 (2)
Ni1—Br2	2.3575 (9)
Ni1—Br3	2.3173 (8)

Data collection: CrysAlis PRO (Oxford Diffraction, 2012 $[Oxford Diffraction (2012). CrysAlis PRO. Agilent Technologies, Yarnton, England.]$ ); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

CCDC reference: 982220

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: 10.1107/S160053681400292X/hy2642sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681400292X/hy2642Isup2.hkl

checkCIF report

Comment top

There is a considerable interest in the development of new late transition metal catalysts for the polymerization of α-olefins since Brookhart et al. discovered highly active α-diimine nickel catalysts (Johnson et al., 1995; Killian et al., 1996). The ligand structure has a dramatic effect on the reactivity of organometallic complexes (Popeney et al., 2011; Popeney & Guan, 2010). Advances in the field of homogeneous catalysis have led to the synthesis of well defined transition metal complexes capable of catalyzing a wide range of organic transformations. It is well known that the Lewis acid catalyzed Friedel-Crafts alkylation of substituted aromatic rings is a highly versatile C—C bond forming method. In this study, we designed and synthesized the title compound, and its molecular structure was characterized by X-ray diffraction. The dihedral angle formed between the benzene ring and phenylethyl ring is 47.1 (1)°.

Related literature top

For background to α-diimine nickel catalysts, see: Johnson et al. (1995); Killian et al. (1996). For the effect of ligand structure on the reactivity of organometallic complexes, see: Popeney & Guan (2010); Popeney et al. (2011).

Experimental top

Formic acid (0.5 ml) was added to a stirred solution of 2,3-butanedione (0.09 g, 1.00 mmol) and 2,6-diethyl-4-phenylbenzenamine (0.45 g, 2.00 mmol) in ethanol (10 ml). The mixture was refluxed for 24 h, then cooled and the precipitate was separated by filtration. The solid was recrystallized from EtOH/CH₂Cl₂ (v/v, 10:1), washed and dried under vacuum to give bis[N,N'-(2,6-diethyl-4-(1-phenyl)imino]-1,2-dimethylethane (yield: 0.69 g, 85%). Analysis, calculated for C₃₆H₄₀N₂: C 86.35, H 8.05, N 5.59%; found: C 84.96, H 7.21, N 7.82%.

NiBr₂(DME) (0.13 g, 1.20 mmol), bis[N,N'-(2,6-diethyl-4-(1-phenyl)imino]-1,2-dimethylethane (0.20 g, 4.00 mmol) and dichloromethane (40 ml) were mixed in a Schlenk flask and stirred at room temperature for 24 h. The resulting suspension was filtered. The solvent was removed under vacuum and the residue was washed with diethyl ether (15 ml) three times, and then dried under vacuum at room temperature to give the title compound (yield: 0.63 g, 82%). Analysis, calculated for C₃₆H₄₀Br₂N₂Ni: C 60.12, H 5.61, N 3.89%; found: C 59.88, H 5.31, N 3.56%. FT-IR (KBr, cm^-1): 1649 (C═N). Crystals suitable for X-ray structure determination were grown from a solution of the title compound in a mixture of cyclohexane/dichloromethane (v/v, 1:4).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2012); cell refinement: CrysAlis PRO (Oxford Diffraction, 2012); data reduction: CrysAlis PRO (Oxford Diffraction, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. Molecular structure of the title compound, showing the 30% probability level ellipsoids. [Symmetry code: (a) x, y, 3/2-z.]

[N,N'-Bis(2,6-diethyl-4-phenylphenyl)butane-2,3-diimine-κ²N,N']dibromidonickel(II) top

Crystal data top

[NiBr₂(C₃₆H₄₀N₂)]	D_x = 1.457 Mg m⁻³
M_r = 719.19	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pnam	Cell parameters from 2436 reflections
a = 15.6587 (5) Å	θ = 3.5–26.1°
b = 6.9359 (3) Å	µ = 3.06 mm⁻¹
c = 30.1928 (16) Å	T = 293 K
V = 3279.2 (2) Å³	Block, brown
Z = 4	0.42 × 0.38 × 0.35 mm
F(000) = 1472

Data collection top

Oxford Diffraction SuperNova CCD diffractometer	3415 independent reflections
Radiation source: fine-focus sealed tube	2376 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.046
ω scans	θ_max = 26.4°, θ_min = 3.0°
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2012)	h = −19→18
T_min = 0.508, T_max = 1.000	k = −8→4
10334 measured reflections	l = −37→22

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.096	H-atom parameters constrained
S = 1.02	w = 1/[σ²(F_o²) + (0.0361P)² + 2.0948P] where P = (F_o² + 2F_c²)/3
3415 reflections	(Δ/σ)_max < 0.001
193 parameters	Δρ_max = 0.53 e Å⁻³
0 restraints	Δρ_min = −0.53 e Å⁻³

Crystal data top

[NiBr₂(C₃₆H₄₀N₂)]	V = 3279.2 (2) Å³
M_r = 719.19	Z = 4
Orthorhombic, Pnam	Mo Kα radiation
a = 15.6587 (5) Å	µ = 3.06 mm⁻¹
b = 6.9359 (3) Å	T = 293 K
c = 30.1928 (16) Å	0.42 × 0.38 × 0.35 mm

Data collection top

Oxford Diffraction SuperNova CCD diffractometer	3415 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2012)	2376 reflections with I > 2σ(I)
T_min = 0.508, T_max = 1.000	R_int = 0.046
10334 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.043	0 restraints
wR(F²) = 0.096	H-atom parameters constrained
S = 1.02	Δρ_max = 0.53 e Å⁻³
3415 reflections	Δρ_min = −0.53 e Å⁻³
193 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

	x	y	z	U_iso*/U_eq
Ni1	0.34408 (3)	0.82145 (10)	0.7500	0.03485 (18)
Br2	0.28258 (4)	0.51120 (8)	0.7500	0.05577 (19)
Br3	0.49179 (3)	0.84183 (12)	0.7500	0.0705 (2)
N1	0.26850 (15)	0.9588 (4)	0.70741 (8)	0.0293 (6)
C1	0.28083 (18)	0.9383 (5)	0.66015 (10)	0.0292 (7)
C2	0.20665 (19)	1.0521 (5)	0.72490 (10)	0.0311 (8)
C3	0.23084 (19)	0.8070 (5)	0.63611 (11)	0.0330 (8)
C4	0.3703 (2)	0.9915 (5)	0.59746 (11)	0.0345 (8)
H4	0.4167	1.0528	0.5844	0.041*
C5	0.2544 (2)	0.7728 (5)	0.59207 (11)	0.0379 (8)
H5	0.2217	0.6882	0.5753	0.046*
C6	0.3243 (2)	0.8598 (5)	0.57262 (11)	0.0347 (8)
C7	0.34987 (18)	1.0362 (5)	0.64119 (10)	0.0309 (7)
C8	0.3998 (2)	1.1906 (5)	0.66489 (12)	0.0420 (9)
H8A	0.3808	1.1971	0.6954	0.050*
H8B	0.4598	1.1556	0.6650	0.050*
C9	0.0769 (2)	0.7102 (8)	0.62840 (16)	0.0748 (15)
H9A	0.0857	0.6469	0.6005	0.112*
H9B	0.0627	0.8430	0.6234	0.112*
H9C	0.0310	0.6482	0.6440	0.112*
C10	0.1368 (2)	1.1541 (6)	0.70058 (12)	0.0476 (9)
H10A	0.0831	1.0933	0.7070	0.071*
H10B	0.1475	1.1479	0.6693	0.071*
H10C	0.1348	1.2865	0.7098	0.071*
C11	0.3499 (2)	0.8120 (5)	0.52645 (11)	0.0411 (9)
C12	0.2902 (3)	0.8027 (6)	0.49250 (12)	0.0540 (11)
H12	0.2330	0.8278	0.4984	0.065*
C13	0.1566 (2)	0.6983 (6)	0.65535 (12)	0.0475 (10)
H13A	0.1725	0.5639	0.6585	0.057*
H13B	0.1448	0.7483	0.6847	0.057*
C14	0.3154 (3)	0.7564 (7)	0.44983 (13)	0.0664 (13)
H14	0.2752	0.7525	0.4272	0.080*
C15	0.3988 (4)	0.7166 (7)	0.44081 (14)	0.0742 (15)
H15	0.4151	0.6847	0.4121	0.089*
C16	0.4587 (3)	0.7232 (8)	0.47362 (15)	0.0754 (15)
H16	0.5156	0.6956	0.4673	0.091*
C17	0.4343 (3)	0.7713 (7)	0.51643 (13)	0.0603 (12)
H17	0.4753	0.7763	0.5387	0.072*
C18	0.3901 (3)	1.3857 (6)	0.64409 (15)	0.0692 (13)
H18A	0.4087	1.3804	0.6138	0.104*
H18B	0.4241	1.4776	0.6600	0.104*
H18C	0.3312	1.4240	0.6451	0.104*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ni1	0.0328 (3)	0.0534 (4)	0.0183 (3)	0.0117 (3)	0.000	0.000
Br2	0.0802 (4)	0.0450 (3)	0.0421 (3)	0.0080 (3)	0.000	0.000
Br3	0.0341 (3)	0.1250 (6)	0.0523 (4)	0.0136 (3)	0.000	0.000
N1	0.0306 (13)	0.0418 (16)	0.0154 (12)	0.0013 (12)	0.0013 (11)	−0.0002 (12)
C1	0.0321 (16)	0.0389 (19)	0.0165 (15)	0.0037 (15)	−0.0012 (13)	0.0011 (14)
C2	0.0314 (16)	0.0382 (19)	0.0236 (17)	−0.0002 (14)	−0.0044 (14)	0.0020 (15)
C3	0.0342 (16)	0.041 (2)	0.0241 (17)	−0.0025 (15)	−0.0030 (14)	0.0060 (16)
C4	0.0348 (16)	0.045 (2)	0.0239 (16)	−0.0035 (16)	0.0037 (15)	0.0028 (17)
C5	0.0451 (19)	0.044 (2)	0.0244 (17)	−0.0068 (17)	−0.0058 (16)	−0.0037 (17)
C6	0.0417 (18)	0.041 (2)	0.0209 (16)	0.0002 (16)	−0.0033 (15)	−0.0004 (16)
C7	0.0334 (16)	0.037 (2)	0.0222 (16)	0.0030 (15)	−0.0022 (14)	−0.0015 (15)
C8	0.0433 (19)	0.049 (2)	0.0339 (19)	−0.0061 (18)	−0.0022 (16)	−0.0062 (19)
C9	0.050 (2)	0.118 (4)	0.056 (3)	−0.031 (3)	−0.008 (2)	0.008 (3)
C10	0.048 (2)	0.061 (2)	0.0336 (19)	0.0162 (19)	−0.0063 (17)	0.003 (2)
C11	0.060 (2)	0.042 (2)	0.0215 (17)	−0.0061 (18)	0.0019 (17)	−0.0008 (17)
C12	0.068 (2)	0.066 (3)	0.028 (2)	−0.016 (2)	−0.0033 (19)	−0.002 (2)
C13	0.049 (2)	0.060 (3)	0.034 (2)	−0.014 (2)	0.0001 (17)	0.009 (2)
C14	0.102 (4)	0.076 (3)	0.022 (2)	−0.026 (3)	−0.013 (2)	−0.003 (2)
C15	0.124 (4)	0.072 (3)	0.027 (2)	−0.011 (3)	0.019 (3)	−0.007 (2)
C16	0.090 (3)	0.098 (4)	0.038 (3)	0.010 (3)	0.024 (3)	−0.007 (3)
C17	0.063 (3)	0.090 (3)	0.028 (2)	0.009 (2)	0.0031 (19)	−0.007 (2)
C18	0.104 (3)	0.053 (3)	0.050 (3)	−0.022 (3)	0.011 (3)	−0.009 (2)

Geometric parameters (Å, º) top

Ni1—N1	1.991 (2)	C9—H9A	0.9600
Ni1—Br2	2.3575 (9)	C9—H9B	0.9600
Ni1—Br3	2.3173 (8)	C9—H9C	0.9600
N1—C2	1.279 (4)	C10—H10A	0.9600
N1—C1	1.447 (4)	C10—H10B	0.9600
C1—C7	1.399 (4)	C10—H10C	0.9600
C1—C3	1.403 (4)	C11—C17	1.386 (5)
C2—C10	1.496 (4)	C11—C12	1.388 (5)
C2—C2ⁱ	1.516 (6)	C12—C14	1.385 (6)
C3—C5	1.400 (5)	C12—H12	0.9300
C3—C13	1.503 (4)	C13—H13A	0.9700
C4—C6	1.384 (5)	C13—H13B	0.9700
C4—C7	1.393 (4)	C14—C15	1.363 (6)
C4—H4	0.9300	C14—H14	0.9300
C5—C6	1.381 (5)	C15—C16	1.365 (7)
C5—H5	0.9300	C15—H15	0.9300
C6—C11	1.488 (4)	C16—C17	1.389 (5)
C7—C8	1.507 (4)	C16—H16	0.9300
C8—C18	1.499 (6)	C17—H17	0.9300
C8—H8A	0.9700	C18—H18A	0.9600
C8—H8B	0.9700	C18—H18B	0.9600
C9—C13	1.492 (5)	C18—H18C	0.9600

N1ⁱ—Ni1—N1	80.49 (14)	C13—C9—H9C	109.5
N1ⁱ—Ni1—Br3	124.35 (7)	H9A—C9—H9C	109.5
N1—Ni1—Br3	124.35 (7)	H9B—C9—H9C	109.5
N1ⁱ—Ni1—Br2	101.19 (8)	C2—C10—H10A	109.5
N1—Ni1—Br2	101.19 (8)	C2—C10—H10B	109.5
Br3—Ni1—Br2	117.61 (4)	H10A—C10—H10B	109.5
C2—N1—C1	123.9 (3)	C2—C10—H10C	109.5
C2—N1—Ni1	115.2 (2)	H10A—C10—H10C	109.5
C1—N1—Ni1	120.70 (19)	H10B—C10—H10C	109.5
C7—C1—C3	122.3 (3)	C17—C11—C12	118.1 (3)
C7—C1—N1	117.3 (3)	C17—C11—C6	120.4 (3)
C3—C1—N1	120.0 (3)	C12—C11—C6	121.4 (3)
N1—C2—C10	126.2 (3)	C14—C12—C11	120.4 (4)
N1—C2—C2ⁱ	114.40 (17)	C14—C12—H12	119.8
C10—C2—C2ⁱ	119.41 (18)	C11—C12—H12	119.8
C5—C3—C1	117.0 (3)	C9—C13—C3	114.1 (3)
C5—C3—C13	119.1 (3)	C9—C13—H13A	108.7
C1—C3—C13	123.9 (3)	C3—C13—H13A	108.7
C6—C4—C7	122.7 (3)	C9—C13—H13B	108.7
C6—C4—H4	118.6	C3—C13—H13B	108.7
C7—C4—H4	118.6	H13A—C13—H13B	107.6
C6—C5—C3	122.6 (3)	C15—C14—C12	120.4 (4)
C6—C5—H5	118.7	C15—C14—H14	119.8
C3—C5—H5	118.7	C12—C14—H14	119.8
C5—C6—C4	118.1 (3)	C14—C15—C16	120.5 (4)
C5—C6—C11	121.0 (3)	C14—C15—H15	119.8
C4—C6—C11	121.0 (3)	C16—C15—H15	119.8
C4—C7—C1	117.2 (3)	C15—C16—C17	119.6 (4)
C4—C7—C8	119.3 (3)	C15—C16—H16	120.2
C1—C7—C8	123.5 (3)	C17—C16—H16	120.2
C18—C8—C7	113.0 (3)	C11—C17—C16	121.0 (4)
C18—C8—H8A	109.0	C11—C17—H17	119.5
C7—C8—H8A	109.0	C16—C17—H17	119.5
C18—C8—H8B	109.0	C8—C18—H18A	109.5
C7—C8—H8B	109.0	C8—C18—H18B	109.5
H8A—C8—H8B	107.8	H18A—C18—H18B	109.5
C13—C9—H9A	109.5	C8—C18—H18C	109.5
C13—C9—H9B	109.5	H18A—C18—H18C	109.5
H9A—C9—H9B	109.5	H18B—C18—H18C	109.5

N1ⁱ—Ni1—N1—C2	−5.1 (3)	C7—C4—C6—C11	−178.2 (3)
Br3—Ni1—N1—C2	−130.5 (2)	C6—C4—C7—C1	1.4 (5)
Br2—Ni1—N1—C2	94.5 (2)	C6—C4—C7—C8	−176.1 (3)
N1ⁱ—Ni1—N1—C1	179.54 (19)	C3—C1—C7—C4	−3.0 (5)
Br3—Ni1—N1—C1	54.2 (3)	N1—C1—C7—C4	169.6 (3)
Br2—Ni1—N1—C1	−80.8 (2)	C3—C1—C7—C8	174.4 (3)
C2—N1—C1—C7	110.0 (4)	N1—C1—C7—C8	−13.0 (5)
Ni1—N1—C1—C7	−75.1 (3)	C4—C7—C8—C18	63.1 (4)
C2—N1—C1—C3	−77.2 (4)	C1—C7—C8—C18	−114.3 (4)
Ni1—N1—C1—C3	97.7 (3)	C5—C6—C11—C17	−132.5 (4)
C1—N1—C2—C10	0.4 (5)	C4—C6—C11—C17	46.9 (5)
Ni1—N1—C2—C10	−174.8 (3)	C5—C6—C11—C12	46.1 (5)
C1—N1—C2—C2ⁱ	179.5 (2)	C4—C6—C11—C12	−134.4 (4)
Ni1—N1—C2—C2ⁱ	4.3 (2)	C17—C11—C12—C14	−0.8 (6)
C7—C1—C3—C5	1.8 (5)	C6—C11—C12—C14	−179.5 (4)
N1—C1—C3—C5	−170.6 (3)	C5—C3—C13—C9	−52.4 (5)
C7—C1—C3—C13	179.7 (3)	C1—C3—C13—C9	129.8 (4)
N1—C1—C3—C13	7.2 (5)	C11—C12—C14—C15	1.0 (7)
C1—C3—C5—C6	1.1 (5)	C12—C14—C15—C16	−0.5 (7)
C13—C3—C5—C6	−176.8 (3)	C14—C15—C16—C17	−0.1 (8)
C3—C5—C6—C4	−2.7 (5)	C12—C11—C17—C16	0.2 (7)
C3—C5—C6—C11	176.8 (3)	C6—C11—C17—C16	178.9 (4)
C7—C4—C6—C5	1.3 (5)	C15—C16—C17—C11	0.3 (8)

Symmetry code: (i) x, y, −z+3/2.

Selected bond lengths (Å) top

Ni1—N1	1.991 (2)	Ni1—Br3	2.3173 (8)
Ni1—Br2	2.3575 (9)

Acknowledgements

We thank the National Natural Science Foundation of China (grant No. 20964003) for funding. We also thank the Key Laboratory of Eco-Environment-Related Polymer Materials of the Ministry of Education and the Key Laboratory of Polymer Materials of Gansu Province (Northwest Normal University) for financial support.

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