Bis(pyridine-2-carboxyl­ato-κ2N,O)copper(II)]–benzene-1,3,5-tri­carb­oxy­lic acid–water (1/2/2)

Zhang, W.; Zhang, B.; Sun, Q.

doi:10.1107/S2414314621006726

metal-organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 6| Part 7| July 2021| x210672

https://doi.org/10.1107/S2414314621006726

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Bis(pyridine-2-carboxylato-κ²N,O)copper(II)]–benzene-1,3,5-tricarboxylic acid–water (1/2/2)

Wenkai Zhang,^a ^* Bingguang Zhang ^a and Qiaozhen Sun ^b

^aKey Laboratory of Catalysis and Materials Sciences of the State Ethnic Affairs, Commission & Ministry of Education, College of Chemistry and Material Science, South-Central University for Nationalities, Wuhan 430074, People's Republic of China, and ^bKey Laboratory of Non-ferrous Metals of the Ministry of Education, School of Materials Science and Engineering, Central South University, Changsha, 410083, People's Republic of China
^*Correspondence e-mail: 3092809@mail.scuec.edu.cn

Edited by R. J. Butcher, Howard University, USA (Received 13 May 2021; accepted 28 June 2021; online 9 July 2021)

In the title complex, [Cu(C₆H₄O₂N)₂]·2C₉H₆O₆·2H₂O, the Cu²⁺ ion lies on a center of inversion and coordinates with symmetry related pyridine nitrogen and carboxyl oxygen atoms from two pyridine-2-carboxylic acid anions, giving rise to a square-planar coordination geometry. There are weak axial bonds between Cu and an O atom of a symmetry-related trimesic acid moieties [Cu⋯O = 2.837 (2) Å] The Cu⋯O weak interactions and hydrogen bonds stabilize the whole structure.

Keywords: crystal structure; mixed ligands coordination polymer; copper carboxylates; hydrogen bond.

CCDC reference: 2092720

Structure description

The asymmetric unit of the title compound contains half copper center, one pyridine-2-carboxylic acid anion, one BTC (benzene-1,3,5-tricarboxylic acid) ligand and one crystal water molecule (Fig. 1). The Cu²⁺ ion lies on the symmetry center and is coordinated by two symmetry-related pyridine nitrogen atoms and two symmetry-related carboxyl oxygen atoms, giving rise to a square-planar coordination geometry. In the axial position, a very weak interaction Cu1⋯O3 [2.837 (2) Å] is observed. Interestingly, the 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene ligand decomposed during the hydrothermal process and is oxidized into pyridine-2-carboxylic acid. According to our earlier research, the occurrence of oxidation may be caused by excess of Cu^II salt, which may act as an oxidative agent to promote the formation of the carboxyl group (Sun et al., 2016 ). Each pyridine-2-carboxylic acid anion coordinates with one Cu²⁺ ion in a bidentate N,O-chelated mode, forming a five-membered ring.

Figure 1
The title compound showing the atom-labelling scheme with displacement ellipsoids drawn at the 30% probability level. Unlabelled atoms are generated by the symmetry operation −x, −y, −z. Hydrogen bonds are shown by dashed lines

In the crystal, C—H⋯O and O—H⋯O hydrogen bonds (Table 1) and together with weak Cu⋯O interactions link the complex molecules into a three-dimensional framework (Fig. 2). Although the O1⋯C9 and O6⋯C7 distances [3.002 (3)and 3.014 (3) Å, respectively] between the two symmetry-related BTC³⁻ ligands (symmetry code: −x, −y, −1 − z) are short, there are no π–π interactions because the inter-centroid distance between the two benzene rings is 5.4029 (15) Å, which is much larger than the normal π–π stacking distance of 3.3–3.8 Å. The shortest distance between the two carbon atoms (C1 and C1′) is 3.379 (4) Å. The other C⋯C distances of the two rings are longer than 3.94 Å. In addition, the distance between the centroid of one benzene ring and the C atoms of another is longer than 4.28 Å.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2⋯O5ⁱ	0.82	1.84	2.621 (2)	158
O4—H4⋯O3ⁱⁱ	0.82	1.85	2.659 (3)	167
O6—H6⋯OW1ⁱⁱⁱ	0.82	1.73	2.553 (3)	176
C10—H10⋯O7^iv	0.93	2.66	3.121 (3)	112
C13—H13⋯O4^v	0.93	2.61	3.454 (4)	152
OW1—HW1A⋯O8^vi	0.85	1.88	2.729 (3)	174
OW1—HW1A⋯O7^vi	0.85	2.66	3.259 (3)	129
OW1—HW1B⋯O1	0.85	2.02	2.872 (3)	175
Symmetry codes: (i) ; (ii) ; (iii) x+1, y+1, z; (iv) ; (v) ; (vi) .

Figure 2
The packing of the title compound. Hydrogen bonds and Cu⋯O interactions are shown as dashed lines.

Synthesis and crystallization

A mixture of trimesic acid (21 mg, 0.1 mmol), 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene (2-bpdb, 11 mg, 0.05 mmol) and CuCl₂·2H₂O (51 mg, 0.3 mmol) in 5 mL of distilled H₂O was stirred for 10 min in air, and then the mixture was turned into a Parr Teflon-lined stainless steel vessel and heated at 160°C for 60 h. Dark-red crystals suitable for X-ray diffraction were obtained in a yield of 78% (based on CuCl₂·2H₂O).

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	[Cu(C₆H₄NO₂)₂]·2C₉H₆O₆·2H₂O
M_r	764.05
Crystal system, space group	Triclinic, P $[\overline{1}]$
Temperature (K)	296
a, b, c (Å)	7.9262 (6), 8.5356 (6), 12.3629 (9)
α, β, γ (°)	107.081 (2), 90.644 (2), 108.679 (2)
V (Å³)	752.26 (10)
Z	1
Radiation type	Mo Kα
μ (mm⁻¹)	0.82
Crystal size (mm)	0.31 × 0.14 × 0.12

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2015 )
T_min, T_max	0.639, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	14996, 3473, 2501
R_int	0.062
(sin θ/λ)_max (Å⁻¹)	0.651

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.047, 0.123, 1.06
No. of reflections	3473
No. of parameters	238
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.41, −0.46
Computer programs: APEX2 and SAINT (Bruker, 2015), SHELXTL (Sheldrick, 2008 ) and SHELXL2014/7 (Sheldrick, 2015 ).

Structural data

CCDC reference: 2092720

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314621006726/bv4039sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314621006726/bv4039Isup3.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2015); cell refinement: SAINT (Bruker, 2015); data reduction: SAINT (Bruker, 2015); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014/7 (Sheldrick, 2015); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Bis(pyridine-2-carboxylato-κ²N,O)copper(II)]–benzene-1,3,5-tricarboxylic acid–water (1/2/2) top

Crystal data top

[Cu(C₆H₄NO₂)₂]·2C₉H₆O₆·2H₂O	Z = 1
M_r = 764.05	F(000) = 391
Triclinic, P1	D_x = 1.687 Mg m⁻³
a = 7.9262 (6) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.5356 (6) Å	Cell parameters from 5514 reflections
c = 12.3629 (9) Å	θ = 3.1–26.9°
α = 107.081 (2)°	µ = 0.82 mm⁻¹
β = 90.644 (2)°	T = 296 K
γ = 108.679 (2)°	Prism, red
V = 752.26 (10) Å³	0.31 × 0.14 × 0.12 mm

Data collection top

Bruker APEXII CCD diffractometer	2501 reflections with I > 2σ(I)
phi and ω scans	R_int = 0.062
Absorption correction: multi-scan (SADABS; Bruker, 2015)	θ_max = 27.6°, θ_min = 3.1°
T_min = 0.639, T_max = 0.746	h = −10→10
14996 measured reflections	k = −11→11
3473 independent reflections	l = −16→16

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.047	H-atom parameters constrained
wR(F²) = 0.123	w = 1/[σ²(F_o²) + (0.0543P)² + 0.4521P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max < 0.001
3473 reflections	Δρ_max = 0.41 e Å⁻³
238 parameters	Δρ_min = −0.46 e Å⁻³

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. All of the non-hydrogen atoms were refined with anisotropic thermal displacement coefficients. Hydrogen atoms attached to the carbons were placed in their calculated position and refined with a idealized riding model. Those attached to oxygen were first located in a difference Fourier and then refined with a idealized riding model [U_iso(H) = 1.2U_eq(C) or 1.5 U_eq(O)].

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Cu1	0.0000	0.0000	0.0000	0.04024 (18)
O1	−0.1595 (2)	−0.3787 (3)	−0.56042 (16)	0.0418 (5)
O2	−0.1580 (3)	−0.4334 (3)	−0.39491 (18)	0.0456 (5)
H2	−0.2531	−0.5104	−0.4252	0.068*
O3	0.2978 (3)	−0.0951 (3)	−0.08146 (16)	0.0428 (5)
O4	0.5456 (3)	0.0969 (3)	−0.10936 (18)	0.0500 (6)
H4	0.5797	0.0972	−0.0464	0.075*
O5	0.5473 (3)	0.2951 (3)	−0.44481 (17)	0.0453 (5)
O6	0.3404 (2)	0.1325 (2)	−0.59294 (15)	0.0367 (4)
H6	0.4000	0.2025	−0.6230	0.055*
O7	0.1869 (3)	0.1722 (2)	0.11419 (16)	0.0457 (5)
O8	0.3797 (3)	0.4424 (3)	0.15484 (19)	0.0594 (6)
N1	0.0395 (3)	0.1833 (3)	−0.07130 (18)	0.0344 (5)
C1	0.1570 (3)	−0.0820 (3)	−0.4716 (2)	0.0275 (5)
H1	0.1094	−0.1022	−0.5455	0.033*
C2	0.0714 (3)	−0.1918 (3)	−0.4104 (2)	0.0263 (5)
C3	0.1436 (3)	−0.1621 (3)	−0.3011 (2)	0.0294 (6)
H3	0.0860	−0.2343	−0.2595	0.035*
C4	0.3020 (3)	−0.0248 (3)	−0.2530 (2)	0.0281 (5)
C5	0.3855 (3)	0.0857 (3)	−0.3140 (2)	0.0291 (6)
H5	0.4904	0.1787	−0.2815	0.035*
C6	0.3125 (3)	0.0574 (3)	−0.4232 (2)	0.0268 (5)
C7	−0.0944 (3)	−0.3437 (3)	−0.4643 (2)	0.0296 (6)
C8	0.3841 (3)	−0.0081 (3)	−0.1403 (2)	0.0318 (6)
C9	0.4110 (3)	0.1745 (3)	−0.4883 (2)	0.0299 (6)
C10	−0.0462 (4)	0.1813 (4)	−0.1655 (2)	0.0417 (7)
H10	−0.1388	0.0809	−0.2067	0.050*
C11	−0.0005 (5)	0.3247 (4)	−0.2033 (3)	0.0509 (8)
H11	−0.0636	0.3222	−0.2680	0.061*
C12	0.1394 (5)	0.4710 (4)	−0.1440 (3)	0.0555 (9)
H12	0.1745	0.5675	−0.1696	0.067*
C13	0.2268 (4)	0.4741 (4)	−0.0469 (3)	0.0479 (8)
H13	0.3214	0.5726	−0.0056	0.058*
C14	0.1726 (4)	0.3293 (4)	−0.0113 (2)	0.0363 (6)
C15	0.2557 (4)	0.3172 (4)	0.0947 (2)	0.0396 (7)
OW1	−0.4676 (3)	−0.6609 (3)	−0.69195 (17)	0.0420 (5)
HW1A	−0.5227	−0.6321	−0.7381	0.063*
HW1B	−0.3783	−0.5734	−0.6547	0.063*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cu1	0.0481 (3)	0.0303 (3)	0.0334 (3)	−0.0012 (2)	−0.0049 (2)	0.0132 (2)
O1	0.0319 (10)	0.0412 (11)	0.0375 (11)	−0.0042 (9)	−0.0068 (8)	0.0094 (9)
O2	0.0320 (11)	0.0391 (11)	0.0521 (12)	−0.0131 (9)	−0.0084 (9)	0.0227 (10)
O3	0.0393 (11)	0.0464 (12)	0.0345 (11)	−0.0023 (9)	−0.0033 (8)	0.0197 (9)
O4	0.0395 (11)	0.0524 (13)	0.0460 (12)	−0.0101 (10)	−0.0180 (9)	0.0269 (10)
O5	0.0347 (11)	0.0398 (11)	0.0472 (12)	−0.0118 (9)	−0.0043 (9)	0.0202 (9)
O6	0.0364 (11)	0.0366 (11)	0.0319 (10)	0.0004 (8)	0.0015 (8)	0.0167 (8)
O7	0.0544 (13)	0.0332 (11)	0.0388 (11)	−0.0032 (9)	−0.0106 (9)	0.0162 (9)
O8	0.0581 (14)	0.0435 (13)	0.0561 (14)	−0.0120 (11)	−0.0223 (11)	0.0188 (11)
N1	0.0386 (13)	0.0311 (12)	0.0292 (12)	0.0051 (10)	0.0015 (9)	0.0104 (9)
C1	0.0235 (12)	0.0282 (13)	0.0282 (13)	0.0060 (10)	−0.0004 (10)	0.0084 (10)
C2	0.0204 (12)	0.0231 (12)	0.0328 (13)	0.0043 (10)	0.0006 (10)	0.0085 (10)
C3	0.0253 (13)	0.0264 (13)	0.0352 (14)	0.0033 (10)	0.0021 (10)	0.0140 (11)
C4	0.0266 (13)	0.0259 (12)	0.0291 (13)	0.0048 (10)	−0.0011 (10)	0.0095 (10)
C5	0.0210 (12)	0.0235 (12)	0.0368 (14)	0.0002 (10)	−0.0031 (10)	0.0092 (10)
C6	0.0222 (12)	0.0245 (12)	0.0333 (13)	0.0051 (10)	0.0014 (10)	0.0116 (10)
C7	0.0213 (12)	0.0263 (13)	0.0388 (15)	0.0045 (10)	0.0009 (11)	0.0107 (11)
C8	0.0286 (14)	0.0294 (13)	0.0322 (14)	0.0021 (11)	−0.0030 (11)	0.0106 (11)
C9	0.0259 (13)	0.0275 (13)	0.0362 (14)	0.0068 (11)	0.0033 (11)	0.0124 (11)
C10	0.0466 (17)	0.0358 (16)	0.0341 (15)	0.0054 (13)	−0.0028 (12)	0.0083 (12)
C11	0.069 (2)	0.0491 (19)	0.0354 (16)	0.0176 (17)	−0.0004 (15)	0.0176 (14)
C12	0.076 (2)	0.0401 (17)	0.0501 (19)	0.0084 (17)	0.0044 (17)	0.0258 (15)
C13	0.0525 (18)	0.0347 (16)	0.0460 (18)	−0.0019 (14)	−0.0004 (14)	0.0158 (13)
C14	0.0352 (15)	0.0346 (15)	0.0347 (15)	0.0056 (12)	0.0037 (11)	0.0112 (12)
C15	0.0407 (16)	0.0376 (16)	0.0331 (15)	0.0033 (13)	−0.0006 (12)	0.0115 (12)
OW1	0.0400 (12)	0.0408 (11)	0.0403 (12)	0.0014 (9)	−0.0043 (9)	0.0192 (9)

Geometric parameters (Å, º) top

Cu1—O7ⁱ	1.9204 (18)	C2—C3	1.380 (3)
Cu1—O7	1.9204 (18)	C2—C7	1.495 (3)
Cu1—N1ⁱ	1.956 (2)	C3—C4	1.391 (3)
Cu1—N1	1.956 (2)	C3—H3	0.9300
Cu1—O3	2.837 (2)	C4—C5	1.388 (3)
O1—C7	1.203 (3)	C4—C8	1.479 (3)
O2—C7	1.313 (3)	C5—C6	1.385 (3)
O2—H2	0.8200	C5—H5	0.9300
O3—C8	1.246 (3)	C6—C9	1.497 (3)
O4—C8	1.281 (3)	C10—C11	1.379 (4)
O4—H4	0.8200	C10—H10	0.9300
O5—C9	1.210 (3)	C11—C12	1.373 (4)
O6—C9	1.303 (3)	C11—H11	0.9300
O6—H6	0.8200	C12—C13	1.369 (4)
O7—C15	1.278 (3)	C12—H12	0.9300
O8—C15	1.227 (3)	C13—C14	1.374 (4)
N1—C10	1.335 (3)	C13—H13	0.9300
N1—C14	1.347 (3)	C14—C15	1.505 (4)
C1—C6	1.385 (3)	OW1—HW1A	0.8499
C1—C2	1.390 (3)	OW1—HW1B	0.8499
C1—H1	0.9300

O7ⁱ—Cu1—O7	180.0 (2)	C4—C5—H5	120.0
O7ⁱ—Cu1—N1ⁱ	84.32 (8)	C5—C6—C1	119.8 (2)
O7—Cu1—N1ⁱ	95.68 (8)	C5—C6—C9	118.4 (2)
O7ⁱ—Cu1—N1	95.68 (8)	C1—C6—C9	121.7 (2)
O7—Cu1—N1	84.32 (8)	O1—C7—O2	124.7 (2)
N1ⁱ—Cu1—N1	180.0	O1—C7—C2	123.2 (2)
O7ⁱ—Cu1—O3	99.58 (8)	O2—C7—C2	112.1 (2)
O7—Cu1—O3	80.42 (8)	O3—C8—O4	123.3 (2)
N1ⁱ—Cu1—O3	85.19 (8)	O3—C8—C4	120.2 (2)
N1—Cu1—O3	94.81 (8)	O4—C8—C4	116.4 (2)
C7—O2—H2	109.5	O5—C9—O6	124.5 (2)
C8—O3—Cu1	113.90 (18)	O5—C9—C6	120.8 (2)
C8—O4—H4	109.5	O6—C9—C6	114.7 (2)
C9—O6—H6	109.5	N1—C10—C11	121.5 (3)
C15—O7—Cu1	114.81 (17)	N1—C10—H10	119.2
C10—N1—C14	119.2 (2)	C11—C10—H10	119.2
C10—N1—Cu1	129.42 (19)	C12—C11—C10	119.1 (3)
C14—N1—Cu1	111.42 (18)	C12—C11—H11	120.5
C6—C1—C2	120.5 (2)	C10—C11—H11	120.5
C6—C1—H1	119.8	C13—C12—C11	119.6 (3)
C2—C1—H1	119.8	C13—C12—H12	120.2
C3—C2—C1	119.5 (2)	C11—C12—H12	120.2
C3—C2—C7	120.5 (2)	C12—C13—C14	119.0 (3)
C1—C2—C7	120.0 (2)	C12—C13—H13	120.5
C2—C3—C4	120.4 (2)	C14—C13—H13	120.5
C2—C3—H3	119.8	N1—C14—C13	121.6 (3)
C4—C3—H3	119.8	N1—C14—C15	114.3 (2)
C5—C4—C3	119.9 (2)	C13—C14—C15	124.1 (3)
C5—C4—C8	121.4 (2)	O8—C15—O7	125.4 (3)
C3—C4—C8	118.6 (2)	O8—C15—C14	119.5 (3)
C6—C5—C4	120.0 (2)	O7—C15—C14	115.1 (2)
C6—C5—H5	120.0	HW1A—OW1—HW1B	109.5

C6—C1—C2—C3	−0.7 (4)	C5—C6—C9—O5	−2.9 (4)
C6—C1—C2—C7	−178.8 (2)	C1—C6—C9—O5	−179.6 (2)
C1—C2—C3—C4	−0.8 (4)	C5—C6—C9—O6	175.6 (2)
C7—C2—C3—C4	177.3 (2)	C1—C6—C9—O6	−1.1 (4)
C2—C3—C4—C5	1.7 (4)	C14—N1—C10—C11	0.6 (4)
C2—C3—C4—C8	−174.1 (2)	Cu1—N1—C10—C11	179.5 (2)
C3—C4—C5—C6	−1.0 (4)	N1—C10—C11—C12	1.7 (5)
C8—C4—C5—C6	174.6 (2)	C10—C11—C12—C13	−2.1 (5)
C4—C5—C6—C1	−0.5 (4)	C11—C12—C13—C14	0.3 (5)
C4—C5—C6—C9	−177.2 (2)	C10—N1—C14—C13	−2.4 (4)
C2—C1—C6—C5	1.3 (4)	Cu1—N1—C14—C13	178.4 (2)
C2—C1—C6—C9	178.0 (2)	C10—N1—C14—C15	178.5 (2)
C3—C2—C7—O1	−177.5 (3)	Cu1—N1—C14—C15	−0.6 (3)
C1—C2—C7—O1	0.6 (4)	C12—C13—C14—N1	2.0 (5)
C3—C2—C7—O2	2.0 (3)	C12—C13—C14—C15	−179.1 (3)
C1—C2—C7—O2	−179.9 (2)	Cu1—O7—C15—O8	−177.8 (3)
Cu1—O3—C8—O4	113.7 (3)	Cu1—O7—C15—C14	2.5 (3)
Cu1—O3—C8—C4	−67.3 (3)	N1—C14—C15—O8	179.1 (3)
C5—C4—C8—O3	171.8 (3)	C13—C14—C15—O8	0.1 (5)
C3—C4—C8—O3	−12.5 (4)	N1—C14—C15—O7	−1.2 (4)
C5—C4—C8—O4	−9.2 (4)	C13—C14—C15—O7	179.7 (3)
C3—C4—C8—O4	166.5 (2)

Symmetry code: (i) −x, −y, −z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O5ⁱⁱ	0.82	1.84	2.621 (2)	158
O4—H4···O3ⁱⁱⁱ	0.82	1.85	2.659 (3)	167
O6—H6···OW1^iv	0.82	1.73	2.553 (3)	176
C10—H10···O7ⁱ	0.93	2.66	3.121 (3)	112
C13—H13···O4^v	0.93	2.61	3.454 (4)	152
OW1—HW1A···O8^vi	0.85	1.88	2.729 (3)	174
OW1—HW1A···O7^vi	0.85	2.66	3.259 (3)	129
OW1—HW1B···O1	0.85	2.02	2.872 (3)	175

Symmetry codes: (i) −x, −y, −z; (ii) x−1, y−1, z; (iii) −x+1, −y, −z; (iv) x+1, y+1, z; (v) −x+1, −y+1, −z; (vi) x−1, y−1, z−1.

Funding information

This work was supported financially by the National Natural Science Foundation of China (No. 51604307).

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