Dibromido[(S)-2-(pyrrolidin-2-yl)-1H-benzimidazole]zinc(II)

Dai, W.; Fu, D.-W.

doi:10.1107/S1600536808019168

metal-organic compounds

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ISSN: 2056-9890

Volume 64| Part 8| August 2008| Page m1016

doi:10.1107/S1600536808019168

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Dibromido[(S)-2-(pyrrolidin-2-yl)-1H-benzimidazole]zinc(II)

Wei Dai ^a and Da-Wei Fu ^a ^*

^aOrdered Matter Science Research Center, College of Chemistry and Chemical Engineering, Southeast University, Nanjing 210096, People's Republic of China
^*Correspondence e-mail: fudavid88@yahoo.com.cn

(Received 19 June 2008; accepted 24 June 2008; online 9 July 2008)

The title compound, [ZnBr₂(C₁₁H₁₃N₃)], was synthesized by hydrothermal reaction of ZnBr₂ and (S)-2-(pyrrolidin-2-yl)-1H-benzimidazole. The Zn^II atom has a distorted tetrahedral geometry and is coordinated by two N atoms from the chelating organic ligand and two terminal Br⁻ anions. In the crystal structure, molecules are linked into a chain along the [101] direction by N—H⋯Br and C—H⋯Br hydrogen bonds.

Related literature

For physical properties such as fluorescence and dielectric behaviors of metal-organic coordination compounds, see: Aminabhavi et al. (1986 ); Ye et al. (2008 ); Fu et al. (2007 ).

Experimental

Crystal data

[ZnBr₂(C₁₁H₁₃N₃)]
M_r = 412.43
Monoclinic, P 2₁ /n
a = 8.953 (3) Å
b = 11.668 (2) Å
c = 13.318 (2) Å
β = 91.443 (3)°
V = 1390.9 (6) Å³
Z = 4
Mo Kα radiation
μ = 7.49 mm⁻¹
T = 298 (2) K
0.30 × 0.25 × 0.15 mm

Data collection

Rigaku Mercury2 diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005 ) T_min = 0.459, T_max = 0.982 (expected range = 0.152–0.325)
13896 measured reflections
3179 independent reflections
2426 reflections with I > 2σ(I)
R_int = 0.065

Refinement

R[F² > 2σ(F²)] = 0.047
wR(F²) = 0.114
S = 0.99
3179 reflections
154 parameters
H-atom parameters constrained
Δρ_max = 0.67 e Å⁻³
Δρ_min = −1.00 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Br1—Zn1	2.3642 (8)
Zn1—N2	2.011 (3)
Zn1—N1	2.075 (4)
Zn1—Br2	2.3319 (7)

N2—Zn1—N1	82.35 (14)
N2—Zn1—Br2	112.70 (10)
N1—Zn1—Br2	117.89 (10)
N2—Zn1—Br1	118.99 (11)
N1—Zn1—Br1	110.08 (11)
Br2—Zn1—Br1	112.03 (3)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3C⋯Br1ⁱ	0.86	2.74	3.516 (4)	150
C4—H4A⋯Br1ⁱⁱ	0.98	2.86	3.637 (5)	137
C1—H1A⋯Cg1ⁱⁱⁱ	0.97	2.78	3.673 (6)	153
Symmetry codes: (i) $[x-{\script{1\over 2}}, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]$ ; (ii) -x, -y+2, -z+1; (iii) $[x-{\script{1\over 2}}, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]$ . Cg1 is the centroid of the C6–C11 ring.

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear; data reduction: CrystalClear; 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: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808019168/ci2621sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808019168/ci2621Isup2.hkl

checkCIF report

Comment top

Metal-organic coordination compounds provide a class of complexes displaying interesting chemical and physical properties such as fluorescence and dielectric behaviors (Aminabhavi et al., 1986; Ye et al., 2008; Fu et al., 2007). There has been very strong interest in employing crystal-engineering strategies to generate desirable materials by the hydrothermal reaction. Here we report the synthesis and crystal structure of the title compound.

The Zn^II atom has a distorted tetrahedral geometry (Table 1) and is coordinated by two N atoms from the chelating S-2-(pyrrolidin-2-yl)-1H-benzimidazole ligand and two terminal Br^- anions (Fig. 1).

In the crystal structure, N—H···Br and C—H···Br hydrogen bonds (Table 2) link the molecules into a chain along [1 0 1] (Fig.2).

Related literature top

For physical properties such as fluorescence and dielectric behaviors of metal-organic coordination compounds, see: Aminabhavi et al. (1986); Ye et al. (2008); Fu et al. (2007). Cg1 is the centroid of the C6–C11 ring.

Experimental top

The homochiral ligand S-2-(pyrrolidin-2-yl)-1H-benzimidazole was synthesized by reaction of S-pyrrolidine-2-carboxylic acid and benzene-1,2-diamine according to the procedure described in the literature (Aminabhavi et al., 1986). A mixture of S-2-(pyrrolidin-2-yl)-1H-benzimidazole (18.7 mg, 0.1 mmol), ZnBr₂ (33.9 mg, 0.1 mmol) and water (1 ml) sealed in a glass tube was maintained at 343 K. Crystals suitable for X-ray ananlysis were obtained after 3 d.

Computing details top

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); 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: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. A view of the title compound with the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 2. The crystal packing of the title compound, viewed along the b axis. H atoms not involved in hydrogen bonding (dashed lines) have been omitted for clarity.

Dibromido[(S)-2-(pyrrolidin-2-yl)-1H-benzimidazole]zinc(II) top

Crystal data top

[ZnBr₂(C₁₁H₁₃N₃)]	F(000) = 800
M_r = 412.43	D_x = 1.970 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 3615 reflections
a = 8.953 (3) Å	θ = 2.7–27.5°
b = 11.668 (2) Å	µ = 7.49 mm⁻¹
c = 13.318 (2) Å	T = 298 K
β = 91.443 (3)°	Block, colourless
V = 1390.9 (6) Å³	0.30 × 0.25 × 0.15 mm
Z = 4

Data collection top

Rigaku Mercury2 diffractometer	3179 independent reflections
Radiation source: fine-focus sealed tube	2426 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.065
Detector resolution: 13.6612 pixels mm^-1	θ_max = 27.5°, θ_min = 2.7°
ω scans	h = −11→11
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −15→15
T_min = 0.459, T_max = 0.982	l = −17→17
13896 measured reflections

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)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.114	H-atom parameters constrained
S = 0.99	w = 1/[σ²(F_o²) + (0.0563P)²] where P = (F_o² + 2F_c²)/3
3179 reflections	(Δ/σ)_max = 0.001
154 parameters	Δρ_max = 0.67 e Å⁻³
0 restraints	Δρ_min = −1.00 e Å⁻³

Crystal data top

[ZnBr₂(C₁₁H₁₃N₃)]	V = 1390.9 (6) Å³
M_r = 412.43	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 8.953 (3) Å	µ = 7.49 mm⁻¹
b = 11.668 (2) Å	T = 298 K
c = 13.318 (2) Å	0.30 × 0.25 × 0.15 mm
β = 91.443 (3)°

Data collection top

Rigaku Mercury2 diffractometer	3179 independent reflections
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	2426 reflections with I > 2σ(I)
T_min = 0.459, T_max = 0.982	R_int = 0.065
13896 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.047	0 restraints
wR(F²) = 0.114	H-atom parameters constrained
S = 0.99	Δρ_max = 0.67 e Å⁻³
3179 reflections	Δρ_min = −1.00 e Å⁻³
154 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
Br1	0.25768 (6)	0.93780 (4)	0.57154 (4)	0.04999 (18)
Zn1	0.13105 (6)	0.76113 (4)	0.55176 (4)	0.03634 (16)
Br2	0.20151 (7)	0.62945 (5)	0.67586 (4)	0.0600 (2)
C6	0.1068 (5)	0.5895 (4)	0.2708 (3)	0.0378 (10)
N2	0.1146 (4)	0.6901 (3)	0.4143 (2)	0.0344 (8)
N1	−0.0955 (4)	0.7895 (3)	0.5261 (3)	0.0378 (8)
H10B	−0.1140	0.8650	0.5377	0.045*
N3	−0.0296 (4)	0.6401 (3)	0.2863 (3)	0.0391 (9)
H3C	−0.1073	0.6357	0.2471	0.047*
C8	0.3041 (6)	0.4841 (5)	0.2047 (4)	0.0554 (14)
H8A	0.3427	0.4362	0.1559	0.066*
C5	−0.0198 (5)	0.6977 (4)	0.3735 (3)	0.0315 (9)
C11	0.1978 (5)	0.6223 (4)	0.3510 (3)	0.0354 (9)
C7	0.1572 (6)	0.5177 (4)	0.1952 (3)	0.0489 (12)
H7A	0.0955	0.4941	0.1419	0.059*
C3	−0.2915 (5)	0.6980 (5)	0.4237 (4)	0.0550 (13)
H3A	−0.3632	0.7284	0.3748	0.066*
H3B	−0.2771	0.6170	0.4107	0.066*
C10	0.3458 (6)	0.5868 (5)	0.3582 (4)	0.0508 (12)
H10A	0.4074	0.6090	0.4120	0.061*
C9	0.3976 (6)	0.5188 (5)	0.2844 (4)	0.0555 (14)
H9A	0.4967	0.4949	0.2869	0.067*
C1	−0.1969 (6)	0.7209 (5)	0.5893 (3)	0.0512 (13)
H1A	−0.2104	0.7573	0.6539	0.061*
H1B	−0.1578	0.6442	0.6002	0.061*
C4	−0.1416 (5)	0.7637 (4)	0.4201 (3)	0.0361 (10)
H4A	−0.1568	0.8357	0.3834	0.043*
C2	−0.3426 (6)	0.7174 (6)	0.5290 (4)	0.0631 (15)
H2A	−0.4059	0.6553	0.5510	0.076*
H2B	−0.3965	0.7892	0.5344	0.076*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0629 (3)	0.0386 (3)	0.0474 (3)	−0.0098 (2)	−0.0209 (2)	0.0027 (2)
Zn1	0.0395 (3)	0.0392 (3)	0.0299 (3)	−0.0022 (2)	−0.0093 (2)	−0.0028 (2)
Br2	0.0757 (4)	0.0521 (3)	0.0509 (3)	−0.0016 (3)	−0.0220 (3)	0.0139 (2)
C6	0.040 (2)	0.042 (2)	0.032 (2)	−0.001 (2)	−0.0023 (19)	−0.0055 (18)
N2	0.0326 (18)	0.041 (2)	0.0290 (17)	−0.0002 (16)	−0.0077 (15)	−0.0026 (15)
N1	0.041 (2)	0.0366 (19)	0.0357 (19)	−0.0010 (17)	−0.0034 (16)	−0.0067 (16)
N3	0.035 (2)	0.050 (2)	0.0319 (18)	−0.0031 (17)	−0.0084 (16)	−0.0051 (16)
C8	0.057 (3)	0.063 (3)	0.046 (3)	0.018 (3)	0.014 (3)	−0.013 (3)
C5	0.034 (2)	0.035 (2)	0.0255 (19)	−0.0055 (18)	−0.0032 (17)	0.0030 (17)
C11	0.031 (2)	0.041 (2)	0.033 (2)	−0.0023 (19)	−0.0051 (18)	−0.0002 (18)
C7	0.058 (3)	0.054 (3)	0.035 (2)	0.001 (3)	−0.004 (2)	−0.012 (2)
C3	0.035 (3)	0.077 (4)	0.053 (3)	−0.008 (3)	0.002 (2)	−0.015 (3)
C10	0.039 (3)	0.067 (3)	0.046 (3)	0.002 (3)	−0.008 (2)	−0.010 (2)
C9	0.041 (3)	0.076 (4)	0.050 (3)	0.014 (3)	0.004 (2)	−0.006 (3)
C1	0.048 (3)	0.068 (3)	0.038 (3)	−0.009 (3)	0.004 (2)	0.004 (2)
C4	0.033 (2)	0.044 (3)	0.031 (2)	0.0022 (19)	−0.0080 (18)	0.0031 (18)
C2	0.046 (3)	0.087 (4)	0.057 (3)	−0.002 (3)	0.002 (3)	0.004 (3)

Geometric parameters (Å, º) top

Br1—Zn1	2.3642 (8)	C5—C4	1.484 (6)
Zn1—N2	2.011 (3)	C11—C10	1.390 (6)
Zn1—N1	2.075 (4)	C7—H7A	0.93
Zn1—Br2	2.3319 (7)	C3—C2	1.504 (7)
C6—N3	1.377 (6)	C3—C4	1.547 (6)
C6—C11	1.382 (6)	C3—H3A	0.97
C6—C7	1.393 (6)	C3—H3B	0.97
N2—C5	1.311 (5)	C10—C9	1.354 (7)
N2—C11	1.387 (5)	C10—H10A	0.93
N1—C1	1.488 (6)	C9—H9A	0.93
N1—C4	1.492 (5)	C1—C2	1.515 (7)
N1—H10B	0.91	C1—H1A	0.97
N3—C5	1.343 (5)	C1—H1B	0.97
N3—H3C	0.86	C4—H4A	0.98
C8—C7	1.376 (7)	C2—H2A	0.97
C8—C9	1.395 (7)	C2—H2B	0.97
C8—H8A	0.93

N2—Zn1—N1	82.35 (14)	C6—C7—H7A	122.2
N2—Zn1—Br2	112.70 (10)	C2—C3—C4	103.8 (4)
N1—Zn1—Br2	117.89 (10)	C2—C3—H3A	111.0
N2—Zn1—Br1	118.99 (11)	C4—C3—H3A	111.0
N1—Zn1—Br1	110.08 (11)	C2—C3—H3B	111.0
Br2—Zn1—Br1	112.03 (3)	C4—C3—H3B	111.0
N3—C6—C11	105.8 (4)	H3A—C3—H3B	109.0
N3—C6—C7	132.1 (4)	C9—C10—C11	118.0 (5)
C11—C6—C7	122.0 (4)	C9—C10—H10A	121.0
C5—N2—C11	106.7 (3)	C11—C10—H10A	121.0
C5—N2—Zn1	113.3 (3)	C10—C9—C8	120.8 (5)
C11—N2—Zn1	139.5 (3)	C10—C9—H9A	119.6
C1—N1—C4	105.6 (3)	C8—C9—H9A	119.6
C1—N1—Zn1	115.4 (3)	N1—C1—C2	104.1 (4)
C4—N1—Zn1	111.7 (3)	N1—C1—H1A	110.9
C1—N1—H10B	108.0	C2—C1—H1A	110.9
C4—N1—H10B	108.0	N1—C1—H1B	110.9
Zn1—N1—H10B	108.0	C2—C1—H1B	110.9
C5—N3—C6	107.8 (3)	H1A—C1—H1B	109.0
C5—N3—H3C	126.1	C5—C4—N1	108.1 (3)
C6—N3—H3C	126.1	C5—C4—C3	113.8 (4)
C7—C8—C9	122.8 (5)	N1—C4—C3	106.9 (3)
C7—C8—H8A	118.6	C5—C4—H4A	109.3
C9—C8—H8A	118.6	N1—C4—H4A	109.3
N2—C5—N3	111.4 (4)	C3—C4—H4A	109.3
N2—C5—C4	122.6 (4)	C3—C2—C1	102.7 (4)
N3—C5—C4	126.0 (4)	C3—C2—H2A	111.2
C6—C11—N2	108.2 (4)	C1—C2—H2A	111.2
C6—C11—C10	120.8 (4)	C3—C2—H2B	111.2
N2—C11—C10	130.9 (4)	C1—C2—H2B	111.2
C8—C7—C6	115.6 (4)	H2A—C2—H2B	109.1
C8—C7—H7A	122.2

N1—Zn1—N2—C5	2.2 (3)	Zn1—N2—C11—C6	170.4 (3)
Br2—Zn1—N2—C5	119.3 (3)	C5—N2—C11—C10	−179.8 (5)
Br1—Zn1—N2—C5	−106.5 (3)	Zn1—N2—C11—C10	−9.2 (8)
N1—Zn1—N2—C11	−168.0 (5)	C9—C8—C7—C6	0.1 (8)
Br2—Zn1—N2—C11	−50.9 (5)	N3—C6—C7—C8	179.6 (5)
Br1—Zn1—N2—C11	83.2 (5)	C11—C6—C7—C8	−1.4 (7)
N2—Zn1—N1—C1	110.8 (3)	C6—C11—C10—C9	−0.2 (8)
Br2—Zn1—N1—C1	−0.8 (3)	N2—C11—C10—C9	179.3 (5)
Br1—Zn1—N1—C1	−131.0 (3)	C11—C10—C9—C8	−1.1 (8)
N2—Zn1—N1—C4	−9.8 (3)	C7—C8—C9—C10	1.2 (9)
Br2—Zn1—N1—C4	−121.4 (3)	C4—N1—C1—C2	−32.6 (5)
Br1—Zn1—N1—C4	108.4 (3)	Zn1—N1—C1—C2	−156.5 (3)
C11—C6—N3—C5	−1.6 (5)	N2—C5—C4—N1	−14.3 (6)
C7—C6—N3—C5	177.5 (5)	N3—C5—C4—N1	166.5 (4)
C11—N2—C5—N3	−0.8 (5)	N2—C5—C4—C3	−132.8 (4)
Zn1—N2—C5—N3	−174.2 (3)	N3—C5—C4—C3	47.9 (6)
C11—N2—C5—C4	179.8 (4)	C1—N1—C4—C5	−111.7 (4)
Zn1—N2—C5—C4	6.5 (5)	Zn1—N1—C4—C5	14.4 (4)
C6—N3—C5—N2	1.5 (5)	C1—N1—C4—C3	11.1 (5)
C6—N3—C5—C4	−179.2 (4)	Zn1—N1—C4—C3	137.3 (3)
N3—C6—C11—N2	1.1 (5)	C2—C3—C4—C5	133.9 (4)
C7—C6—C11—N2	−178.1 (4)	C2—C3—C4—N1	14.6 (5)
N3—C6—C11—C10	−179.2 (4)	C4—C3—C2—C1	−34.0 (6)
C7—C6—C11—C10	1.6 (7)	N1—C1—C2—C3	41.8 (6)
C5—N2—C11—C6	−0.2 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3C···Br1ⁱ	0.86	2.74	3.516 (4)	150
C4—H4A···Br1ⁱⁱ	0.98	2.86	3.637 (5)	137
C1—H1A···Cg1ⁱⁱⁱ	0.97	2.78	3.673 (6)	153

Symmetry codes: (i) x−1/2, −y+3/2, z−1/2; (ii) −x, −y+2, −z+1; (iii) x−1/2, −y+3/2, z+1/2.

Experimental details

Crystal data
Chemical formula	[ZnBr₂(C₁₁H₁₃N₃)]
M_r	412.43
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	298
a, b, c (Å)	8.953 (3), 11.668 (2), 13.318 (2)
β (°)	91.443 (3)
V (Å³)	1390.9 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	7.49
Crystal size (mm)	0.30 × 0.25 × 0.15

Data collection
Diffractometer	Rigaku Mercury2 diffractometer
Absorption correction	Multi-scan (CrystalClear; Rigaku, 2005)
T_min, T_max	0.459, 0.982
No. of measured, independent and observed [I > 2σ(I)] reflections	13896, 3179, 2426
R_int	0.065
(sin θ/λ)_max (Å⁻¹)	0.651

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.047, 0.114, 0.99
No. of reflections	3179
No. of parameters	154
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.67, −1.00

Computer programs: CrystalClear (Rigaku, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected geometric parameters (Å, º) top

Br1—Zn1	2.3642 (8)	Zn1—N1	2.075 (4)
Zn1—N2	2.011 (3)	Zn1—Br2	2.3319 (7)

N2—Zn1—N1	82.35 (14)	N2—Zn1—Br1	118.99 (11)
N2—Zn1—Br2	112.70 (10)	N1—Zn1—Br1	110.08 (11)
N1—Zn1—Br2	117.89 (10)	Br2—Zn1—Br1	112.03 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3C···Br1ⁱ	0.86	2.74	3.516 (4)	150
C4—H4A···Br1ⁱⁱ	0.98	2.86	3.637 (5)	137
C1—H1A···Cg1ⁱⁱⁱ	0.97	2.78	3.673 (6)	153

Symmetry codes: (i) x−1/2, −y+3/2, z−1/2; (ii) −x, −y+2, −z+1; (iii) x−1/2, −y+3/2, z+1/2.

Acknowledgements

This work was supported by a Start-up Grant from Southeast University to Professor Ren-Gen Xiong, and a Excellent Doctoral Degree Foundation Grant from Southeast University to DWF.

References

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