metal-organic compounds
Poly[[bis(μ2-6-methylpyrazin-2-carboxylato-κ3N1,O:N4)copper(II)] dihydrate]
aDepartment of Chemistry and Chemical Engineering, Binzhou University, Shandong 256603, People's Republic of China, and bCollege of Chemistry and Chemical Engineering, Liaocheng University, Shandong 252059, People's Republic of China
*Correspondence e-mail: xintingwei@cn.yahoo.com
In the title compound, {[Cu(C6H5N2O2)2]·2H2O}n, the CuII ion (site symmetry ) is coordinated by two N,O-bidentate ligands and two N-monodentate ligands in a distorted CuO2N4 octahedral geometry. Each anion acts as a bridge between two cations, thus forming a two-dimensional polymeric network parallel to the ab plane. The packing is consolidated by O—H⋯O hydrogen bonds. One of the O atoms of the ligand and both water molecules are disordered.
Related literature
For a related structure, see: Yigit et al. (2006). For background to coordination networks, see: Kesanli & Lin (2003); Barnett & Champness (2003).
Experimental
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2003); cell SAINT (Bruker, 2003); data reduction: SAINT; 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
https://doi.org/10.1107/S1600536809041440/hb5123sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536809041440/hb5123Isup2.hkl
4.00 g Potassium permanganate was to be dissolved in 30 ml pure water in a beaker and 1.0 ml 98% H2SO4 was added to the solution. After stiring 10 min, and then added 2,6-dimethylpyrazine to the mixture.The recation was keeping at room temperature for 24 h. The resulting solution was filtered, and the filtrate was left in a beaker, then 2.00 g copper(II) sulfate pentahydrate was added to the filtrate. After stirrng for 20 min s, the copper(II) sulfate pentahydrate was solved completely. The blue solution was kept at the room temperature for two weeks and blue blocks of (I) were obtained. Yield: 86percent, m.p. 551 K. Anal. Calc. for C12H14CuN4O6: C: 38.5567; H:3.7750; N:14.9881; Found:C: 37.67; H: 3.86; N: 14.32%. Selected IR (KBr, cm-1) 3439(w), 2889 (w), 1638(s), 1596 (s), 1536(w), 1409(s), 1364(m), 1275(m), 1149(s), 1151(s), 1034(s), 941(s), 820(m), 800(s), 712(w), 531(m), 471(w).
All H atoms were placed geometrically and treated as riding on their parent atoms with C—H 0.93(pyrazine), C—H 0.97 (methylene) Å [Uiso(H) = 1.2Ueq(C)] and O—H 0.82 Å (hydroxyl) [Uiso(H) = 1.5Ueq(O)].
In recent years,the construction of metal-organic coordination polymers (MOCPs) by metal-directed self- assembly is of great interest not only for their potential applications as functional materials in ion exchange, catalysis, hydrogen storage, and magnetic devices, but also for their aesthetic structural and host–guest chemistry associated with large central cavities. (Kesanli et al., 2003; Barnett et al., 2003). As an extension of this work,the 6-methyl-2- pyrazinecarboxylic acid was chosen due to its chelating coordinated effect leading to a linear metal center.
As shown in Fig.1. X-ray structural analyses of complex (1) reveal the core structure of (1) is the symmetric dinuclear unit of [Cu(L)2(H2O)2] (L = anion of 6-methyl-2- pyrazinecarboxylic acid). Each CuII atom is coordinated to two ligands as well as to the two N atoms of the other two ligands, forming a octahedral coordination conformation.
The ligand forms a coordination polymer with tridentate and monodentate binding of CuII ions at opposite ends of the ligand bridge neighboring units and yield a two-dimensional arrangement running in the ab plane (Fig. 2). Yigit et al. (2006) recently reported a coordination polymer featuring a similar head-to-tail arrangement of pyrazine-2,3,5,6-tetracarboxylic acid. There is intermolecular H-bonds (O3—H3···O4) showed as strong H bond, which link the molecular and water to form host–guest model.
For a related structure, see: Yigit et al. (2006). For background to coordination networks, see: Kesanli & Lin (2003); Barnett & Champness (2003).
Data collection: SMART (Bruker, 2003); cell
SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); 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).Fig. 1. The molecular structure of (I) showing 30% probability displacement ellipsoids. | |
Fig. 2. The crystal packing of (I), viewed approximately along the c axis. |
[Cu(C6H5N2O2)2]·2H2O | F(000) = 382 |
Mr = 373.81 | Dx = 1.576 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 1598 reflections |
a = 8.371 (1) Å | θ = 2.6–26.2° |
b = 9.7901 (11) Å | µ = 1.42 mm−1 |
c = 10.3849 (13) Å | T = 298 K |
β = 112.277 (1)° | Block, blue |
V = 787.55 (16) Å3 | 0.34 × 0.32 × 0.30 mm |
Z = 2 |
Bruker SMART CCD diffractometer | 1388 independent reflections |
Radiation source: fine-focus sealed tube | 1094 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.027 |
ω scans | θmax = 25.0°, θmin = 2.6° |
Absorption correction: multi-scan (SADABS; Bruker, 2003) | h = −9→9 |
Tmin = 0.644, Tmax = 0.675 | k = −11→11 |
3821 measured reflections | l = −12→9 |
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)] = 0.049 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.160 | H-atom parameters constrained |
S = 1.06 | w = 1/[σ2(Fo2) + (0.0987P)2 + 1.8186P] where P = (Fo2 + 2Fc2)/3 |
1388 reflections | (Δ/σ)max = 0.001 |
126 parameters | Δρmax = 1.23 e Å−3 |
0 restraints | Δρmin = −0.47 e Å−3 |
[Cu(C6H5N2O2)2]·2H2O | V = 787.55 (16) Å3 |
Mr = 373.81 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 8.371 (1) Å | µ = 1.42 mm−1 |
b = 9.7901 (11) Å | T = 298 K |
c = 10.3849 (13) Å | 0.34 × 0.32 × 0.30 mm |
β = 112.277 (1)° |
Bruker SMART CCD diffractometer | 1388 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2003) | 1094 reflections with I > 2σ(I) |
Tmin = 0.644, Tmax = 0.675 | Rint = 0.027 |
3821 measured reflections |
R[F2 > 2σ(F2)] = 0.049 | 0 restraints |
wR(F2) = 0.160 | H-atom parameters constrained |
S = 1.06 | Δρmax = 1.23 e Å−3 |
1388 reflections | Δρmin = −0.47 e Å−3 |
126 parameters |
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 | Occ. (<1) | |
Cu1 | 0.5000 | 0.5000 | 0.5000 | 0.0210 (3) | |
N1 | 0.5565 (5) | 0.3429 (4) | 0.3509 (4) | 0.0273 (9) | |
N2 | 0.5246 (5) | 0.1511 (4) | 0.1450 (4) | 0.0270 (9) | |
O1 | 0.2704 (4) | 0.4333 (3) | 0.3861 (3) | 0.0259 (7) | |
O2 | 0.1014 (18) | 0.343 (6) | 0.184 (5) | 0.049 (10) | 0.46 (9) |
O2' | 0.1110 (16) | 0.279 (5) | 0.235 (4) | 0.049 (9) | 0.54 (9) |
O3 | 0.8445 (18) | 0.5171 (12) | 0.0914 (16) | 0.097 (4) | 0.50 |
H3C | 0.9307 | 0.4639 | 0.1248 | 0.116* | 0.50 |
H3D | 0.8631 | 0.5877 | 0.1426 | 0.116* | 0.50 |
O4 | 0.499 (3) | 0.4908 (16) | 0.9398 (18) | 0.126 (6) | 0.50 |
H4D | 0.5904 | 0.5025 | 1.0121 | 0.152* | 0.50 |
H4E | 0.4122 | 0.4929 | 0.9628 | 0.152* | 0.50 |
C1 | 0.2469 (6) | 0.3484 (6) | 0.2899 (6) | 0.0411 (14) | |
C2 | 0.4033 (6) | 0.2942 (5) | 0.2678 (5) | 0.0302 (11) | |
C3 | 0.3863 (6) | 0.1987 (6) | 0.1653 (5) | 0.0337 (12) | |
H3 | 0.2771 | 0.1672 | 0.1096 | 0.040* | |
C4 | 0.6768 (6) | 0.1996 (5) | 0.2266 (5) | 0.0319 (11) | |
H4A | 0.7750 | 0.1682 | 0.2146 | 0.038* | |
C5 | 0.6955 (6) | 0.2969 (5) | 0.3308 (5) | 0.0301 (11) | |
C6 | 0.8676 (7) | 0.3506 (7) | 0.4211 (6) | 0.0496 (16) | |
H6A | 0.8532 | 0.4283 | 0.4721 | 0.074* | |
H6B | 0.9300 | 0.3775 | 0.3644 | 0.074* | |
H6C | 0.9309 | 0.2809 | 0.4850 | 0.074* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cu1 | 0.0214 (5) | 0.0226 (5) | 0.0193 (5) | −0.0019 (3) | 0.0079 (3) | 0.0006 (3) |
N1 | 0.023 (2) | 0.033 (2) | 0.026 (2) | −0.0023 (17) | 0.0093 (16) | −0.0047 (17) |
N2 | 0.025 (2) | 0.031 (2) | 0.027 (2) | −0.0020 (18) | 0.0120 (16) | −0.0056 (17) |
O1 | 0.0234 (16) | 0.0301 (18) | 0.0267 (17) | −0.0018 (14) | 0.0124 (13) | −0.0062 (15) |
O2 | 0.025 (5) | 0.065 (19) | 0.054 (13) | −0.004 (6) | 0.012 (5) | −0.030 (15) |
O2' | 0.025 (4) | 0.065 (17) | 0.054 (11) | −0.004 (5) | 0.012 (5) | −0.030 (12) |
O3 | 0.074 (8) | 0.092 (10) | 0.115 (11) | 0.018 (6) | 0.026 (8) | 0.013 (7) |
O4 | 0.120 (14) | 0.133 (15) | 0.129 (17) | −0.002 (9) | 0.050 (14) | 0.000 (11) |
C1 | 0.019 (3) | 0.058 (4) | 0.045 (3) | −0.004 (2) | 0.010 (2) | −0.019 (3) |
C2 | 0.025 (3) | 0.033 (3) | 0.032 (3) | −0.004 (2) | 0.010 (2) | −0.010 (2) |
C3 | 0.025 (3) | 0.041 (3) | 0.035 (3) | −0.004 (2) | 0.011 (2) | −0.012 (2) |
C4 | 0.023 (3) | 0.040 (3) | 0.034 (3) | 0.002 (2) | 0.012 (2) | −0.007 (2) |
C5 | 0.026 (3) | 0.032 (3) | 0.033 (3) | −0.002 (2) | 0.012 (2) | −0.006 (2) |
C6 | 0.024 (3) | 0.068 (4) | 0.054 (4) | −0.001 (3) | 0.011 (3) | −0.027 (3) |
Cu1—O1i | 1.949 (3) | O3—H3C | 0.8500 |
Cu1—O1 | 1.949 (3) | O3—H3D | 0.8500 |
Cu1—N2ii | 2.064 (4) | O4—O4v | 1.26 (3) |
Cu1—N2iii | 2.064 (4) | O4—H4D | 0.8500 |
Cu1—N1i | 2.354 (4) | O4—H4E | 0.8500 |
Cu1—N1 | 2.354 (4) | C1—C2 | 1.509 (7) |
N1—C2 | 1.333 (6) | C2—C3 | 1.383 (7) |
N1—C5 | 1.336 (6) | C3—H3 | 0.9300 |
N2—C4 | 1.322 (6) | C4—C5 | 1.405 (7) |
N2—C3 | 1.337 (6) | C4—H4A | 0.9300 |
N2—Cu1iv | 2.065 (4) | C5—C6 | 1.486 (7) |
O1—C1 | 1.256 (6) | C6—H6A | 0.9600 |
O2—C1 | 1.30 (3) | C6—H6B | 0.9600 |
O2'—C1 | 1.26 (2) | C6—H6C | 0.9600 |
O1i—Cu1—O1 | 180.0 | H4D—O4—H4E | 109.0 |
O1i—Cu1—N2ii | 89.70 (14) | O1—C1—O2' | 124.0 (8) |
O1—Cu1—N2ii | 90.30 (14) | O1—C1—O2 | 121.0 (11) |
O1i—Cu1—N2iii | 90.30 (14) | O2'—C1—O2 | 36.7 (6) |
O1—Cu1—N2iii | 89.70 (14) | O1—C1—C2 | 118.1 (4) |
N2ii—Cu1—N2iii | 180.0 | O2'—C1—C2 | 115.3 (8) |
O1i—Cu1—N1i | 77.27 (13) | O2—C1—C2 | 116.5 (8) |
O1—Cu1—N1i | 102.73 (13) | N1—C2—C3 | 122.2 (5) |
N2ii—Cu1—N1i | 88.74 (15) | N1—C2—C1 | 116.9 (4) |
N2iii—Cu1—N1i | 91.26 (15) | C3—C2—C1 | 120.9 (4) |
O1i—Cu1—N1 | 102.73 (13) | N2—C3—C2 | 121.0 (4) |
O1—Cu1—N1 | 77.27 (13) | N2—C3—H3 | 119.5 |
N2ii—Cu1—N1 | 91.26 (15) | C2—C3—H3 | 119.5 |
N2iii—Cu1—N1 | 88.74 (15) | N2—C4—C5 | 122.4 (4) |
N1i—Cu1—N1 | 180.0 | N2—C4—H4A | 118.8 |
C2—N1—C5 | 117.4 (4) | C5—C4—H4A | 118.8 |
C2—N1—Cu1 | 106.0 (3) | N1—C5—C4 | 120.0 (4) |
C5—N1—Cu1 | 136.6 (3) | N1—C5—C6 | 118.4 (4) |
C4—N2—C3 | 117.1 (4) | C4—C5—C6 | 121.6 (4) |
C4—N2—Cu1iv | 122.0 (3) | C5—C6—H6A | 109.5 |
C3—N2—Cu1iv | 120.8 (3) | C5—C6—H6B | 109.5 |
C1—O1—Cu1 | 121.7 (3) | H6A—C6—H6B | 109.5 |
H3C—O3—H3D | 108.5 | C5—C6—H6C | 109.5 |
O4v—O4—H4D | 55.8 | H6A—C6—H6C | 109.5 |
O4v—O4—H4E | 53.3 | H6B—C6—H6C | 109.5 |
O1i—Cu1—N1—C2 | −179.1 (3) | C5—N1—C2—C1 | −179.1 (5) |
O1—Cu1—N1—C2 | 0.9 (3) | Cu1—N1—C2—C1 | 0.0 (5) |
N2ii—Cu1—N1—C2 | 90.9 (3) | O1—C1—C2—N1 | −1.4 (8) |
N2iii—Cu1—N1—C2 | −89.1 (3) | O2'—C1—C2—N1 | −164 (3) |
N1i—Cu1—N1—C2 | 168 (100) | O2—C1—C2—N1 | 155 (4) |
O1i—Cu1—N1—C5 | −0.4 (5) | O1—C1—C2—C3 | 178.9 (5) |
O1—Cu1—N1—C5 | 179.6 (5) | O2'—C1—C2—C3 | 17 (3) |
N2ii—Cu1—N1—C5 | −90.4 (5) | O2—C1—C2—C3 | −24 (4) |
N2iii—Cu1—N1—C5 | 89.6 (5) | C4—N2—C3—C2 | −0.2 (8) |
N1i—Cu1—N1—C5 | −13 (100) | Cu1iv—N2—C3—C2 | 176.2 (4) |
O1i—Cu1—O1—C1 | 5 (100) | N1—C2—C3—N2 | −0.1 (8) |
N2ii—Cu1—O1—C1 | −93.0 (4) | C1—C2—C3—N2 | 179.6 (5) |
N2iii—Cu1—O1—C1 | 87.0 (4) | C3—N2—C4—C5 | 0.0 (8) |
N1i—Cu1—O1—C1 | 178.2 (4) | Cu1iv—N2—C4—C5 | −176.3 (4) |
N1—Cu1—O1—C1 | −1.8 (4) | C2—N1—C5—C4 | −0.8 (7) |
Cu1—O1—C1—O2' | 163 (3) | Cu1—N1—C5—C4 | −179.5 (4) |
Cu1—O1—C1—O2 | −153 (4) | C2—N1—C5—C6 | 179.4 (5) |
Cu1—O1—C1—C2 | 2.4 (7) | Cu1—N1—C5—C6 | 0.7 (8) |
C5—N1—C2—C3 | 0.6 (7) | N2—C4—C5—N1 | 0.5 (8) |
Cu1—N1—C2—C3 | 179.7 (4) | N2—C4—C5—C6 | −179.7 (5) |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x, −y+1/2, z+1/2; (iii) −x+1, y+1/2, −z+1/2; (iv) −x+1, y−1/2, −z+1/2; (v) −x+1, −y+1, −z+2. |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3C···O2vi | 0.85 | 1.78 | 2.624 (3) | 175 |
O3—H3C···O2′vi | 0.85 | 2.36 | 3.181 (3) | 163 |
O3—H3D···O2′iii | 0.85 | 2.23 | 3.074 (2) | 175 |
O4—H4D···O3vii | 0.85 | 1.97 | 2.73 (3) | 147 |
O4—H4E···O3i | 0.85 | 2.01 | 2.77 (2) | 150 |
Symmetry codes: (i) −x+1, −y+1, −z+1; (iii) −x+1, y+1/2, −z+1/2; (vi) x+1, y, z; (vii) x, y, z+1. |
Experimental details
Crystal data | |
Chemical formula | [Cu(C6H5N2O2)2]·2H2O |
Mr | 373.81 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 298 |
a, b, c (Å) | 8.371 (1), 9.7901 (11), 10.3849 (13) |
β (°) | 112.277 (1) |
V (Å3) | 787.55 (16) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 1.42 |
Crystal size (mm) | 0.34 × 0.32 × 0.30 |
Data collection | |
Diffractometer | Bruker SMART CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2003) |
Tmin, Tmax | 0.644, 0.675 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3821, 1388, 1094 |
Rint | 0.027 |
(sin θ/λ)max (Å−1) | 0.596 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.049, 0.160, 1.06 |
No. of reflections | 1388 |
No. of parameters | 126 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 1.23, −0.47 |
Computer programs: SMART (Bruker, 2003), SAINT (Bruker, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
Cu1—O1 | 1.949 (3) | Cu1—N1 | 2.354 (4) |
Cu1—N2i | 2.064 (4) |
Symmetry code: (i) −x+1, y+1/2, −z+1/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3C···O2ii | 0.85 | 1.78 | 2.624 (3) | 175 |
O3—H3C···O2'ii | 0.85 | 2.36 | 3.181 (3) | 163 |
O3—H3D···O2'i | 0.85 | 2.23 | 3.074 (2) | 175 |
O4—H4D···O3iii | 0.85 | 1.97 | 2.73 (3) | 147 |
O4—H4E···O3iv | 0.85 | 2.01 | 2.77 (2) | 150 |
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) x+1, y, z; (iii) x, y, z+1; (iv) −x+1, −y+1, −z+1. |
References
Barnett, S. A. & Champness, N. R. (2003). Coord. Chem. Rev. 246, 145–168. Web of Science CrossRef CAS Google Scholar
Bruker (2003). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Kesanli, B. & Lin, W. B. (2003). Coord. Chem. Rev. 246, 305–326. Web of Science CrossRef CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Yigit, M. V., Wang, Y., Moulton, B. & MacDonald, J. C. (2006). Cryst. Growth Des. 6, 829–832. Web of Science CrossRef CAS Google Scholar
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In recent years,the construction of metal-organic coordination polymers (MOCPs) by metal-directed self- assembly is of great interest not only for their potential applications as functional materials in ion exchange, catalysis, hydrogen storage, and magnetic devices, but also for their aesthetic structural and host–guest chemistry associated with large central cavities. (Kesanli et al., 2003; Barnett et al., 2003). As an extension of this work,the 6-methyl-2- pyrazinecarboxylic acid was chosen due to its chelating coordinated effect leading to a linear metal center.
As shown in Fig.1. X-ray structural analyses of complex (1) reveal the core structure of (1) is the symmetric dinuclear unit of [Cu(L)2(H2O)2] (L = anion of 6-methyl-2- pyrazinecarboxylic acid). Each CuII atom is coordinated to two ligands as well as to the two N atoms of the other two ligands, forming a octahedral coordination conformation.
The ligand forms a coordination polymer with tridentate and monodentate binding of CuII ions at opposite ends of the ligand bridge neighboring units and yield a two-dimensional arrangement running in the ab plane (Fig. 2). Yigit et al. (2006) recently reported a coordination polymer featuring a similar head-to-tail arrangement of pyrazine-2,3,5,6-tetracarboxylic acid. There is intermolecular H-bonds (O3—H3···O4) showed as strong H bond, which link the molecular and water to form host–guest model.