metal-organic compounds
Poly[[diaqua[μ-1,4-bis(pyridin-4-ylmethyl)piperazine-κ2N:N′]{μ-2,2′-[(1,4-phenylene)bis(oxy)]diacetato-κ2O:O′}cobalt(II)] pentahydrate]
aLyman Briggs College, Department of Chemistry, Michigan State University, East Lansing, MI 48825, USA
*Correspondence e-mail: laduca@msu.edu
In the title compound, {[Co(C10H8O6)(C16H20N4)(H2O)2]·5H2O}n, octahedrally coordinated CoII ions on crystallographic inversion centres are bound by trans O atoms belonging to two hydroquinone-O,O′-diacetate (hqda) anions {systematic name: 2,2′-[(1,4-phenylene)bis(oxy)]diacetate}, two trans-pyridine N-donor atoms from two bis(pyridin-4-ylmethyl)piperazine (4-bpmp) ligands, and two trans aqua ligands. The exobidentate hqda and 4-bpmp ligands form [Co(hqda)(4-bpmp)(H2O)2]n coordination polymer layers parallel to (110) that are anchored into the full by O—H⋯O hydrogen bonding between aqua ligands and ligated hqda O atoms. Disordered water molecules of crystallization occupy incipient channels along [100]. However, these could not modeled reliably and so they were treated with SQUEEZE in PLATON [Spek (2009). Acta Cryst. D65, 148–155]; the crystal data take the presence of these molecules into account. The crystal under investigation was twinned by non-merohedry, the twin fraction of the components being 53.3% and 46.7%. Only data from the major twin component were used in the refinement.
CCDC reference: 997809
Related literature
For the preparation of bis(4-pyridymethyl)piperazine, see: Niu et al. (2001). For the preparation of divalent metal terephthalate coordination polymers containing 4-bpmp, see: Farnum et al. (2013).
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2012); cell SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2.
Supporting information
CCDC reference: 997809
10.1107/S1600536814008745/tk5308sup1.cif
contains datablocks I, pub. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536814008745/tk5308Isup2.hkl
Some divalent metal terephthalate coordination polymers with bis(pyridin-4-ylmethyl)piperazine (4-bpmp) coligands show intriguing entangled topologies. (Farnum et al., 2013). We hoped to expand the scope of these materials by using a para aromatic dicarboxylate with longer pendant arms, such as hydroquinone-O,O'-diacetic acid (H2hqda). The title compound was obtained as pink crystals through the hydrothermal reaction of cobalt nitrate, H2hqda, and 4-bpmp.
The
of the title compound contains a divalent cobalt atom on a crystallographic inversion centre, an aqua ligand, half of a hqda ligand whose centroid rests on another crystallographic inversion centre, and one half of a 4-bpmp ligand whose centroid rests on a third crystallographic inversion centre.The cobalt atom is octahedrally coordinated (Fig. 1), with the equatorial plane containing trans pyridyl N atom donors from two 4-bpmp ligands and trans O atom donors from monodentate carboxylate groups belonging to two hqda ligands. The aqua ligands are located in the axial positions.
The Co atoms are connected by exobidentate, bis(monodentate) hqda ligands to form [Co(hqda)(H2O)2]n coordination polymer chains that are oriented parallel to [0 1 0]. Each individual chain is linked to two others by tethering 4-bpmp ligands, to construct [Co(hqda)(4-bpmp)(H2O)2]n coordination polymer layers parallel to (110) (Fig. 2). As each cobalt atom is connected to four others, the underlying topology of the layer is a (4,4) rectangular grid. The internuclear Co···Co through-space distances across the grid apertures are 13.17 Å and 25.14 Å.
Individual [Co(hqda)(4-bpmp)(H2O)2]n layers stack in a AAA pattern along the a crystal direction (Fig. 3). The supramolecular O—H···O hydrogen bonding between aqua ligands in one layer and ligated hqda O atoms in two others provides the impetus for the formation of the three-dimensional
of the title compound.Disordered water molecules of crystallization occupy incipient channels along [1 0 0]. These could not be refined well, and thus their electron density was modeled using the SQUEEZE subroutine of PLATON (Spek, 2009). The resulting analysis indicated the presence of approximately five water molecules per
in a region comprising 20.6% of the total volume.Cobalt(II) nitrate hexahydrate and hydroquinone-O,O'-diacetic acid (H2hqda) were obtained commercially. Bis(4-pyridymethyl)piperazine (4-bpmp) was prepared via a published procedure (Niu et al., 2001). A mixture of cobalt(II) nitrate hexahydrate (68 mg, 0.23 mmol), H2hqda (84 mg, 0.37 mmol), 4-bpmp (99 mg, 0.37 mmol), 0.25 ml of a 1.0 M NaOH solution and 10.0 g water (550 mmol) was placed into a 23 ml Teflon-lined Parr acid digestion bomb, which was then heated under autogenous pressure at 393 K for 24 h. Pink plates of the title compound were obtained in a multi-phase mixture.
Data collection: APEX2 (Bruker, 2012); cell
SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).[Co(C10H8O6)(C16H20N4)(H2O)2]·5H2O | Z = 1 |
Mr = 677.57 | F(000) = 357 |
Triclinic, P1 | Dx = 1.475 Mg m−3 |
a = 5.7727 (8) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 10.3421 (15) Å | Cell parameters from 2300 reflections |
c = 13.1675 (19) Å | θ = 2.5–25.0° |
α = 87.175 (2)° | µ = 0.63 mm−1 |
β = 78.856 (2)° | T = 173 K |
γ = 81.474 (2)° | Plate, pink |
V = 762.61 (19) Å3 | 0.19 × 0.17 × 0.05 mm |
Bruker APEXII CCD diffractometer | 2786 independent reflections |
Radiation source: fine-focus sealed tube | 2032 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.053 |
ϕ and ω scans | θmax = 25.4°, θmin = 2.0° |
Absorption correction: multi-scan (TWINABS; Sheldrick, 2003) | h = −6→6 |
Tmin = 0.676, Tmax = 0.745 | k = −12→12 |
13385 measured reflections | l = 0→15 |
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)] = 0.093 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.228 | H-atom parameters constrained |
S = 1.10 | w = 1/[σ2(Fo2) + (0.0164P)2 + 9.3P] where P = (Fo2 + 2Fc2)/3 |
2786 reflections | (Δ/σ)max < 0.001 |
179 parameters | Δρmax = 0.71 e Å−3 |
0 restraints | Δρmin = −0.89 e Å−3 |
[Co(C10H8O6)(C16H20N4)(H2O)2]·5H2O | γ = 81.474 (2)° |
Mr = 677.57 | V = 762.61 (19) Å3 |
Triclinic, P1 | Z = 1 |
a = 5.7727 (8) Å | Mo Kα radiation |
b = 10.3421 (15) Å | µ = 0.63 mm−1 |
c = 13.1675 (19) Å | T = 173 K |
α = 87.175 (2)° | 0.19 × 0.17 × 0.05 mm |
β = 78.856 (2)° |
Bruker APEXII CCD diffractometer | 2786 independent reflections |
Absorption correction: multi-scan (TWINABS; Sheldrick, 2003) | 2032 reflections with I > 2σ(I) |
Tmin = 0.676, Tmax = 0.745 | Rint = 0.053 |
13385 measured reflections |
R[F2 > 2σ(F2)] = 0.093 | 0 restraints |
wR(F2) = 0.228 | H-atom parameters constrained |
S = 1.10 | Δρmax = 0.71 e Å−3 |
2786 reflections | Δρmin = −0.89 e Å−3 |
179 parameters |
Experimental. TWINABS-2012/1 (Bruker,2012) was used for absorption correction. For component 1: wR2(int) was 0.0549 before and 0.0460 after correction. The Ratio of minimum to maximum transmission is 0.91. The λ/2 correction factor is Not present For component 2: wR2(int) was 0.0664 before and 0.0469 after correction. The Ratio of minimum to maximum transmission not present. The λ/2 correction factor is Not present Final HKLF 4 output contains 13385 reflections, Rint = 0.0533 (6718 with I > 3sig(I), Rint = 0.0400) |
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. |
x | y | z | Uiso*/Ueq | ||
Co1 | 0.5000 | 0.0000 | 0.0000 | 0.0217 (4) | |
O4 | 0.8245 (8) | 0.0527 (5) | −0.0875 (4) | 0.0259 (11) | |
H4A | 0.9116 | 0.0861 | −0.0468 | 0.039* | |
H4B | 0.7974 | 0.1148 | −0.1372 | 0.039* | |
O1 | 0.2947 (8) | 0.1293 (4) | −0.0851 (4) | 0.0284 (12) | |
O2 | 0.5742 (10) | 0.1838 (6) | −0.2164 (4) | 0.0437 (15) | |
O3 | −0.0339 (10) | 0.3206 (5) | −0.1427 (5) | 0.0442 (15) | |
N1 | 0.4646 (10) | 0.1467 (5) | 0.1144 (5) | 0.0262 (14) | |
N2 | 0.1474 (11) | 0.4777 (6) | 0.4001 (5) | 0.0335 (15) | |
C13 | 0.3664 (14) | 0.1882 (7) | −0.1687 (6) | 0.0318 (18) | |
C12 | 0.1723 (15) | 0.2740 (8) | −0.2163 (7) | 0.043 (2) | |
H12A | 0.2401 | 0.3498 | −0.2528 | 0.052* | |
H12B | 0.1244 | 0.2227 | −0.2684 | 0.052* | |
C10 | −0.0057 (15) | 0.4091 (8) | −0.0716 (8) | 0.042 (2) | |
C9 | −0.2010 (14) | 0.4424 (8) | 0.0052 (8) | 0.042 (2) | |
H9 | −0.3397 | 0.4018 | 0.0088 | 0.051* | |
C5 | 0.6335 (14) | 0.1602 (8) | 0.1688 (7) | 0.038 (2) | |
H5 | 0.7780 | 0.1009 | 0.1571 | 0.046* | |
C1 | 0.2635 (13) | 0.2314 (7) | 0.1348 (6) | 0.0335 (18) | |
H1 | 0.1390 | 0.2231 | 0.0988 | 0.040* | |
C6 | 0.3746 (14) | 0.4588 (9) | 0.3307 (6) | 0.0380 (19) | |
H6A | 0.5028 | 0.4440 | 0.3719 | 0.046* | |
H6B | 0.3944 | 0.5396 | 0.2883 | 0.046* | |
C8 | 0.1075 (14) | 0.6027 (8) | 0.4482 (6) | 0.0378 (19) | |
H8A | 0.1156 | 0.6725 | 0.3939 | 0.045* | |
H8B | 0.2350 | 0.6077 | 0.4878 | 0.045* | |
C7 | 0.1316 (15) | 0.3748 (8) | 0.4801 (6) | 0.040 (2) | |
H7A | 0.2605 | 0.3745 | 0.5200 | 0.048* | |
H7B | 0.1524 | 0.2886 | 0.4475 | 0.048* | |
C11 | 0.1974 (15) | 0.4660 (8) | −0.0770 (7) | 0.042 (2) | |
H11 | 0.3332 | 0.4424 | −0.1295 | 0.051* | |
C2 | 0.2273 (13) | 0.3304 (7) | 0.2053 (6) | 0.0305 (17) | |
H2 | 0.0812 | 0.3883 | 0.2166 | 0.037* | |
C3 | 0.4032 (13) | 0.3448 (7) | 0.2590 (6) | 0.0301 (17) | |
C4 | 0.6070 (14) | 0.2550 (8) | 0.2401 (7) | 0.043 (2) | |
H4 | 0.7311 | 0.2593 | 0.2773 | 0.051* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Co1 | 0.0171 (7) | 0.0232 (7) | 0.0226 (8) | 0.0000 (5) | −0.0008 (5) | −0.0004 (5) |
O4 | 0.022 (3) | 0.031 (3) | 0.025 (3) | −0.006 (2) | −0.003 (2) | 0.008 (2) |
O1 | 0.027 (3) | 0.022 (2) | 0.036 (3) | 0.002 (2) | −0.011 (2) | 0.003 (2) |
O2 | 0.036 (3) | 0.059 (4) | 0.035 (3) | −0.018 (3) | −0.001 (3) | 0.022 (3) |
O3 | 0.035 (3) | 0.037 (3) | 0.066 (4) | −0.006 (3) | −0.024 (3) | 0.007 (3) |
N1 | 0.021 (3) | 0.023 (3) | 0.031 (4) | 0.001 (2) | 0.000 (3) | −0.002 (3) |
N2 | 0.036 (4) | 0.035 (4) | 0.026 (4) | 0.001 (3) | −0.001 (3) | −0.004 (3) |
C13 | 0.037 (5) | 0.033 (4) | 0.027 (4) | −0.010 (4) | −0.009 (4) | 0.007 (3) |
C12 | 0.046 (5) | 0.043 (5) | 0.046 (6) | −0.021 (4) | −0.017 (4) | 0.028 (4) |
C10 | 0.036 (5) | 0.027 (4) | 0.070 (7) | −0.010 (4) | −0.024 (4) | 0.019 (4) |
C9 | 0.023 (4) | 0.028 (4) | 0.078 (7) | −0.004 (3) | −0.019 (4) | 0.012 (4) |
C5 | 0.028 (4) | 0.041 (5) | 0.047 (5) | 0.004 (4) | −0.012 (4) | −0.013 (4) |
C1 | 0.027 (4) | 0.034 (4) | 0.037 (5) | 0.009 (3) | −0.010 (3) | −0.003 (3) |
C6 | 0.035 (4) | 0.054 (5) | 0.025 (4) | −0.010 (4) | 0.000 (3) | −0.012 (4) |
C8 | 0.035 (5) | 0.040 (5) | 0.034 (5) | 0.001 (4) | −0.001 (4) | 0.004 (4) |
C7 | 0.038 (5) | 0.040 (5) | 0.039 (5) | 0.014 (4) | −0.012 (4) | −0.009 (4) |
C11 | 0.033 (5) | 0.035 (5) | 0.059 (6) | −0.004 (4) | −0.010 (4) | 0.009 (4) |
C2 | 0.024 (4) | 0.033 (4) | 0.030 (4) | 0.008 (3) | −0.001 (3) | −0.002 (3) |
C3 | 0.027 (4) | 0.034 (4) | 0.025 (4) | −0.008 (3) | 0.008 (3) | 0.000 (3) |
C4 | 0.027 (4) | 0.045 (5) | 0.058 (6) | 0.002 (4) | −0.012 (4) | −0.019 (4) |
Co1—O4 | 2.131 (4) | C9—H9 | 0.9500 |
Co1—O4i | 2.131 (4) | C9—C11ii | 1.375 (12) |
Co1—O1 | 2.084 (5) | C5—H5 | 0.9500 |
Co1—O1i | 2.084 (5) | C5—C4 | 1.363 (11) |
Co1—N1 | 2.151 (6) | C1—H1 | 0.9500 |
Co1—N1i | 2.151 (6) | C1—C2 | 1.382 (10) |
O4—H4A | 0.9131 | C6—H6A | 0.9900 |
O4—H4B | 0.9130 | C6—H6B | 0.9900 |
O1—C13 | 1.260 (9) | C6—C3 | 1.517 (10) |
O2—C13 | 1.237 (9) | C8—H8A | 0.9900 |
O3—C12 | 1.421 (11) | C8—H8B | 0.9900 |
O3—C10 | 1.388 (10) | C8—C7iii | 1.508 (11) |
N1—C5 | 1.343 (10) | C7—C8iii | 1.508 (11) |
N1—C1 | 1.337 (9) | C7—H7A | 0.9900 |
N2—C6 | 1.440 (10) | C7—H7B | 0.9900 |
N2—C8 | 1.435 (10) | C11—C9ii | 1.375 (12) |
N2—C7 | 1.461 (10) | C11—H11 | 0.9500 |
C13—C12 | 1.535 (11) | C2—H2 | 0.9500 |
C12—H12A | 0.9900 | C2—C3 | 1.373 (11) |
C12—H12B | 0.9900 | C3—C4 | 1.376 (11) |
C10—C9 | 1.376 (13) | C4—H4 | 0.9500 |
C10—C11 | 1.377 (11) | ||
O4—Co1—O4i | 180.0 | C11ii—C9—C10 | 120.6 (8) |
O4—Co1—N1i | 85.7 (2) | C11ii—C9—H9 | 119.7 |
O4i—Co1—N1i | 94.3 (2) | N1—C5—H5 | 118.5 |
O4—Co1—N1 | 94.3 (2) | N1—C5—C4 | 123.0 (7) |
O4i—Co1—N1 | 85.7 (2) | C4—C5—H5 | 118.5 |
O1i—Co1—O4 | 87.77 (19) | N1—C1—H1 | 118.2 |
O1—Co1—O4i | 87.77 (18) | N1—C1—C2 | 123.5 (7) |
O1i—Co1—O4i | 92.23 (19) | C2—C1—H1 | 118.2 |
O1—Co1—O4 | 92.23 (19) | N2—C6—H6A | 108.9 |
O1i—Co1—O1 | 180.0 | N2—C6—H6B | 108.9 |
O1i—Co1—N1i | 90.1 (2) | N2—C6—C3 | 113.4 (7) |
O1—Co1—N1 | 90.1 (2) | H6A—C6—H6B | 107.7 |
O1i—Co1—N1 | 89.9 (2) | C3—C6—H6A | 108.9 |
O1—Co1—N1i | 89.9 (2) | C3—C6—H6B | 108.9 |
N1—Co1—N1i | 180.0 (3) | N2—C8—H8A | 109.3 |
Co1—O4—H4A | 112.0 | N2—C8—H8B | 109.3 |
Co1—O4—H4B | 111.7 | N2—C8—C7iii | 111.8 (7) |
H4A—O4—H4B | 106.8 | H8A—C8—H8B | 107.9 |
C13—O1—Co1 | 127.2 (5) | C7iii—C8—H8A | 109.3 |
C10—O3—C12 | 116.7 (7) | C7iii—C8—H8B | 109.3 |
C5—N1—Co1 | 124.3 (5) | N2—C7—C8iii | 110.0 (6) |
C1—N1—Co1 | 119.6 (5) | N2—C7—H7A | 109.7 |
C1—N1—C5 | 116.2 (6) | N2—C7—H7B | 109.7 |
C6—N2—C7 | 111.1 (6) | C8iii—C7—H7A | 109.7 |
C8—N2—C6 | 110.9 (7) | C8iii—C7—H7B | 109.7 |
C8—N2—C7 | 109.3 (6) | H7A—C7—H7B | 108.2 |
O1—C13—C12 | 115.8 (7) | C10—C11—H11 | 120.5 |
O2—C13—O1 | 127.3 (7) | C9ii—C11—C10 | 119.1 (9) |
O2—C13—C12 | 116.9 (7) | C9ii—C11—H11 | 120.5 |
O3—C12—C13 | 113.7 (7) | C1—C2—H2 | 120.1 |
O3—C12—H12A | 108.8 | C3—C2—C1 | 119.8 (7) |
O3—C12—H12B | 108.8 | C3—C2—H2 | 120.1 |
C13—C12—H12A | 108.8 | C2—C3—C6 | 120.6 (7) |
C13—C12—H12B | 108.8 | C2—C3—C4 | 116.6 (7) |
H12A—C12—H12B | 107.7 | C4—C3—C6 | 122.8 (7) |
C9—C10—O3 | 115.6 (7) | C5—C4—C3 | 121.0 (8) |
C9—C10—C11 | 120.3 (9) | C5—C4—H4 | 119.5 |
C11—C10—O3 | 124.1 (9) | C3—C4—H4 | 119.5 |
C10—C9—H9 | 119.7 | ||
Co1—O1—C13—O2 | −1.8 (12) | N1—C1—C2—C3 | −0.3 (12) |
Co1—O1—C13—C12 | 177.7 (5) | N2—C6—C3—C2 | 48.1 (10) |
Co1—N1—C5—C4 | 179.3 (7) | N2—C6—C3—C4 | −135.2 (8) |
Co1—N1—C1—C2 | −178.6 (6) | C12—O3—C10—C9 | −173.6 (7) |
O4—Co1—O1—C13 | 12.3 (6) | C12—O3—C10—C11 | 8.8 (11) |
O4i—Co1—O1—C13 | −167.7 (6) | C10—O3—C12—C13 | 66.9 (9) |
O4i—Co1—N1—C5 | 125.5 (6) | C9—C10—C11—C9ii | −0.8 (13) |
O4—Co1—N1—C5 | −54.5 (6) | C5—N1—C1—C2 | 1.5 (12) |
O4—Co1—N1—C1 | 125.6 (6) | C1—N1—C5—C4 | −0.8 (12) |
O4i—Co1—N1—C1 | −54.4 (6) | C1—C2—C3—C6 | 175.3 (7) |
O1i—Co1—N1—C5 | 33.2 (6) | C1—C2—C3—C4 | −1.6 (12) |
O1—Co1—N1—C5 | −146.8 (6) | C6—N2—C8—C7iii | 179.1 (7) |
O1—Co1—N1—C1 | 33.3 (6) | C6—N2—C7—C8iii | 179.8 (7) |
O1i—Co1—N1—C1 | −146.7 (6) | C6—C3—C4—C5 | −174.6 (8) |
O1—C13—C12—O3 | 26.2 (10) | C8—N2—C6—C3 | −166.4 (7) |
O2—C13—C12—O3 | −154.2 (7) | C8—N2—C7—C8iii | 57.0 (10) |
O3—C10—C9—C11ii | −176.9 (7) | C7—N2—C6—C3 | 71.8 (9) |
O3—C10—C11—C9ii | 176.7 (7) | C7—N2—C8—C7iii | −58.1 (9) |
N1—Co1—O1—C13 | 106.6 (6) | C11—C10—C9—C11ii | 0.8 (13) |
N1i—Co1—O1—C13 | −73.4 (6) | C2—C3—C4—C5 | 2.2 (13) |
N1—C5—C4—C3 | −1.1 (14) |
Symmetry codes: (i) −x+1, −y, −z; (ii) −x, −y+1, −z; (iii) −x, −y+1, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H4A···O1iv | 0.91 | 2.28 | 2.945 (7) | 130 |
O4—H4B···O2 | 0.91 | 1.85 | 2.636 (7) | 143 |
Symmetry code: (iv) x+1, y, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H4A···O1i | 0.91 | 2.28 | 2.945 (7) | 130 |
O4—H4B···O2 | 0.91 | 1.85 | 2.636 (7) | 143 |
Symmetry code: (i) x+1, y, z. |
Acknowledgements
We gratefully acknowledge Lyman Briggs College of Michigan State University for funding this work.
References
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