metal-organic compounds
Diaquabis[5-(pyrazin-2-yl-κN1)-3-(pyridin-3-yl)-1,2,4-triazolido-κN1]cadmium
aCollege of Mechanical & Material Engineering, China Three Gorges University, Yichang 443002, People's Republic of China
*Correspondence e-mail: junzhao08@126.com
In the title compound, [Cd(C11H7N6)2(H2O)2], the CdII cation is located on an inversion center and is coordinated by four N atoms from two 5-(pyrazin-2-yl)-3-(pyridin-3-yl)-1,2,4-triazolide anions and two water molecules in a distorted octahedral geometry. The triazolide ligand is nearly planar: the central triazole ring is oriented at dihedral angles of 4.63 (13) and 8.41 (13)° with respect to the pyrazine and pyridine rings. Intermolecular O—H⋯N hydrogen bonds link the molecules into a two-dimensional supramolecular network parallel to (001).
Related literature
For background to metal-organic frameworks, see: Kitagawa et al. (2004). For 1,2,4-triazole derivatives, see: Chen et al. (2006); Zhang et al. (2005).
Experimental
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2007); cell SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.
Supporting information
https://doi.org/10.1107/S1600536811045545/xu5363sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811045545/xu5363Isup2.hkl
A mixture of 2-(5-(pyridin-3-yl)-4H-1,2,4-triazol-3-yl)pyrazine (0.0224 g, 0.1 mmol), Cd(CH3COO)2.2H2O (0.0266 g, 0.1 mmol), water (10 mL) was stired vigorously for 30 min and then sealed in a Teflon-lined stainless-steel autoclave. The autoclave was heated and maintained at 413 K for 3 d, and then cooled to room temperature at 5 K h-1 to obtain prism crystals suitable for X-ray analysis.
Water H atoms were located in a difference Fourier map and refined with O–H restraint of 0.85±0.01 Å, Uiso(H) = 1.5 Ueq(O). Other H-atoms were positioned geometrically and refined using a riding model with C–H = 0.93 Å, Uiso(H) = 1.2 Ueq(C).
Much effort has been focused on the design and controlled synthesis of metal-organic frameworks or coordination polymers (Kitagawa et al., 2004). 1,2,4-triazole derivatives have received considerable attention, owing to the variety of their coordination modes, and structural features (Chen et al., 2006; Zhang et al., 2005). During the synthesis of polymeric complexes using 2-(5-(pyridin-3-yl)-4H-1,2,4-triazol-3-yl)pyrazine as bridging ligand and, to our surprise, the title monomeric Cd(II) complex was obtained. The title complex, is a crstallographically centrosymmetric mononuclear complex. The CdII cation, which is located on a centre of inversion, is six-coordinated by four N atoms from two chelating 2-(5-(pyridin-3-yl)-1,2,4-triazolido-3-yl)pyrazine ligands and two water O atoms, resulting into a distored octahedral geometry (Fig. 1). In the crystal, intermolecular O–H···N hydrogen bonding interactions (Table 2) link the title complex into a two-dimensional supramolecular network (Fig. 2).
For background to metal-organic frameworks, see: Kitagawa et al. (2004). For 1,2,4-triazole derivatives, see: Chen et al. (2006); Zhang et al. (2005).
Data collection: SMART (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).[Cd(C11H7N6)2(H2O)2] | F(000) = 596 |
Mr = 594.88 | Dx = 1.759 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 2671 reflections |
a = 8.640 (5) Å | θ = 2.4–27.5° |
b = 5.684 (3) Å | µ = 1.02 mm−1 |
c = 23.157 (13) Å | T = 296 K |
β = 99.102 (6)° | Prism, colorless |
V = 1122.9 (11) Å3 | 0.24 × 0.21 × 0.20 mm |
Z = 2 |
Bruker SMART CCD diffractometer | 2571 independent reflections |
Radiation source: fine-focus sealed tube | 2251 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.057 |
φ and ω scans | θmax = 27.5°, θmin = 2.4° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −11→11 |
Tmin = 0.782, Tmax = 0.815 | k = −7→7 |
11387 measured reflections | l = −30→30 |
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)] = 0.032 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.081 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.09 | w = 1/[σ2(Fo2) + (0.0336P)2 + 0.5415P] where P = (Fo2 + 2Fc2)/3 |
2571 reflections | (Δ/σ)max < 0.001 |
175 parameters | Δρmax = 0.38 e Å−3 |
3 restraints | Δρmin = −0.82 e Å−3 |
[Cd(C11H7N6)2(H2O)2] | V = 1122.9 (11) Å3 |
Mr = 594.88 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 8.640 (5) Å | µ = 1.02 mm−1 |
b = 5.684 (3) Å | T = 296 K |
c = 23.157 (13) Å | 0.24 × 0.21 × 0.20 mm |
β = 99.102 (6)° |
Bruker SMART CCD diffractometer | 2571 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2251 reflections with I > 2σ(I) |
Tmin = 0.782, Tmax = 0.815 | Rint = 0.057 |
11387 measured reflections |
R[F2 > 2σ(F2)] = 0.032 | 3 restraints |
wR(F2) = 0.081 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.09 | Δρmax = 0.38 e Å−3 |
2571 reflections | Δρmin = −0.82 e Å−3 |
175 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 | ||
Cd1 | 0.0000 | 1.0000 | 0.0000 | 0.02997 (10) | |
N1 | 0.0416 (2) | 1.1638 (3) | 0.09658 (9) | 0.0272 (4) | |
N2 | 0.0947 (3) | 1.2756 (4) | 0.21582 (9) | 0.0365 (5) | |
N3 | 0.1919 (2) | 0.7738 (3) | 0.05584 (9) | 0.0295 (4) | |
N4 | 0.2884 (2) | 0.5850 (4) | 0.05077 (9) | 0.0306 (4) | |
N5 | 0.3260 (2) | 0.6991 (3) | 0.14563 (9) | 0.0290 (4) | |
N6 | 0.6292 (3) | 0.0309 (4) | 0.09166 (12) | 0.0395 (6) | |
O1 | −0.1880 (2) | 0.7608 (3) | 0.03044 (8) | 0.0343 (4) | |
H1A | −0.263 (3) | 0.840 (5) | 0.0406 (13) | 0.051* | |
H1B | −0.227 (3) | 0.657 (4) | 0.0055 (12) | 0.051* | |
C1 | −0.0256 (3) | 1.3500 (4) | 0.11794 (11) | 0.0321 (5) | |
H1 | −0.0932 | 1.4440 | 0.0925 | 0.039* | |
C2 | 0.0024 (3) | 1.4061 (5) | 0.17639 (12) | 0.0346 (6) | |
H2 | −0.0445 | 1.5399 | 0.1890 | 0.042* | |
C3 | 0.1625 (3) | 1.0904 (5) | 0.19467 (11) | 0.0340 (6) | |
H3 | 0.2281 | 0.9955 | 0.2206 | 0.041* | |
C4 | 0.1390 (3) | 1.0333 (4) | 0.13529 (11) | 0.0257 (5) | |
C5 | 0.2188 (3) | 0.8347 (4) | 0.11250 (10) | 0.0266 (5) | |
C6 | 0.3651 (3) | 0.5483 (4) | 0.10522 (12) | 0.0272 (5) | |
C7 | 0.4792 (3) | 0.3558 (4) | 0.12057 (11) | 0.0288 (5) | |
C8 | 0.5377 (3) | 0.3073 (5) | 0.17899 (12) | 0.0343 (6) | |
H8 | 0.5079 | 0.3996 | 0.2085 | 0.041* | |
C9 | 0.6405 (3) | 0.1208 (5) | 0.19295 (12) | 0.0379 (6) | |
H9 | 0.6810 | 0.0867 | 0.2317 | 0.045* | |
C10 | 0.6809 (3) | −0.0120 (4) | 0.14809 (15) | 0.0387 (7) | |
H10 | 0.7480 | −0.1390 | 0.1576 | 0.046* | |
C11 | 0.5315 (3) | 0.2144 (5) | 0.07830 (12) | 0.0361 (6) | |
H11 | 0.4972 | 0.2485 | 0.0391 | 0.043* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cd1 | 0.03525 (16) | 0.03198 (15) | 0.02068 (15) | 0.00690 (10) | −0.00171 (11) | −0.00100 (9) |
N1 | 0.0299 (10) | 0.0262 (9) | 0.0249 (10) | 0.0034 (8) | 0.0026 (8) | −0.0011 (8) |
N2 | 0.0473 (13) | 0.0357 (11) | 0.0264 (11) | 0.0039 (10) | 0.0051 (10) | −0.0055 (9) |
N3 | 0.0328 (10) | 0.0286 (10) | 0.0265 (11) | 0.0071 (9) | 0.0029 (8) | −0.0022 (8) |
N4 | 0.0332 (11) | 0.0292 (10) | 0.0290 (11) | 0.0085 (9) | 0.0034 (9) | −0.0033 (9) |
N5 | 0.0289 (10) | 0.0302 (10) | 0.0264 (10) | 0.0061 (8) | 0.0001 (8) | −0.0010 (8) |
N6 | 0.0334 (12) | 0.0420 (13) | 0.0434 (15) | 0.0122 (10) | 0.0067 (11) | −0.0048 (10) |
O1 | 0.0345 (9) | 0.0326 (9) | 0.0357 (10) | 0.0041 (8) | 0.0055 (8) | −0.0061 (8) |
C1 | 0.0355 (13) | 0.0287 (12) | 0.0318 (13) | 0.0068 (10) | 0.0044 (11) | 0.0012 (10) |
C2 | 0.0423 (14) | 0.0292 (12) | 0.0342 (14) | 0.0054 (11) | 0.0119 (11) | −0.0028 (11) |
C3 | 0.0411 (14) | 0.0338 (13) | 0.0251 (13) | 0.0057 (11) | −0.0005 (11) | −0.0005 (11) |
C4 | 0.0249 (11) | 0.0282 (11) | 0.0237 (12) | 0.0012 (9) | 0.0029 (9) | 0.0017 (9) |
C5 | 0.0262 (11) | 0.0264 (11) | 0.0269 (12) | 0.0027 (9) | 0.0036 (9) | −0.0001 (9) |
C6 | 0.0237 (11) | 0.0295 (11) | 0.0281 (13) | 0.0035 (9) | 0.0033 (10) | −0.0002 (10) |
C7 | 0.0256 (11) | 0.0282 (11) | 0.0316 (13) | 0.0043 (9) | 0.0018 (10) | 0.0007 (10) |
C8 | 0.0331 (13) | 0.0359 (13) | 0.0330 (14) | 0.0057 (11) | 0.0030 (11) | −0.0010 (11) |
C9 | 0.0355 (14) | 0.0410 (14) | 0.0357 (15) | 0.0077 (12) | 0.0011 (11) | 0.0070 (12) |
C10 | 0.0323 (13) | 0.0335 (14) | 0.0497 (19) | 0.0104 (11) | 0.0045 (13) | 0.0053 (11) |
C11 | 0.0330 (13) | 0.0431 (14) | 0.0315 (14) | 0.0084 (11) | 0.0031 (11) | −0.0025 (11) |
Cd1—O1i | 2.312 (2) | O1—H1A | 0.850 (17) |
Cd1—O1 | 2.312 (2) | O1—H1B | 0.859 (17) |
Cd1—N1i | 2.397 (2) | C1—C2 | 1.374 (4) |
Cd1—N1 | 2.397 (2) | C1—H1 | 0.9300 |
Cd1—N3 | 2.323 (2) | C2—H2 | 0.9300 |
Cd1—N3i | 2.323 (2) | C3—C4 | 1.396 (4) |
N1—C1 | 1.339 (3) | C3—H3 | 0.9300 |
N1—C4 | 1.351 (3) | C4—C5 | 1.464 (3) |
N2—C3 | 1.334 (3) | C6—C7 | 1.478 (3) |
N2—C2 | 1.338 (3) | C7—C11 | 1.396 (4) |
N3—C5 | 1.341 (3) | C7—C8 | 1.395 (4) |
N3—N4 | 1.375 (3) | C8—C9 | 1.388 (4) |
N4—C6 | 1.345 (3) | C8—H8 | 0.9300 |
N5—C5 | 1.347 (3) | C9—C10 | 1.373 (4) |
N5—C6 | 1.351 (3) | C9—H9 | 0.9300 |
N6—C10 | 1.335 (4) | C10—H10 | 0.9300 |
N6—C11 | 1.347 (3) | C11—H11 | 0.9300 |
O1i—Cd1—O1 | 180.00 (9) | N2—C2—C1 | 122.4 (2) |
O1i—Cd1—N3 | 91.20 (8) | N2—C2—H2 | 118.8 |
O1—Cd1—N3 | 88.80 (8) | C1—C2—H2 | 118.8 |
O1i—Cd1—N3i | 88.80 (8) | N2—C3—C4 | 122.8 (2) |
O1—Cd1—N3i | 91.20 (8) | N2—C3—H3 | 118.6 |
N3—Cd1—N3i | 180.00 (9) | C4—C3—H3 | 118.6 |
O1i—Cd1—N1i | 87.30 (7) | N1—C4—C3 | 120.3 (2) |
O1—Cd1—N1i | 92.70 (7) | N1—C4—C5 | 117.6 (2) |
N3—Cd1—N1i | 107.04 (7) | C3—C4—C5 | 122.1 (2) |
N3i—Cd1—N1i | 72.96 (7) | N3—C5—N5 | 114.0 (2) |
O1i—Cd1—N1 | 92.70 (7) | N3—C5—C4 | 122.2 (2) |
O1—Cd1—N1 | 87.30 (7) | N5—C5—C4 | 123.8 (2) |
N3—Cd1—N1 | 72.96 (7) | N4—C6—N5 | 114.3 (2) |
N3i—Cd1—N1 | 107.04 (7) | N4—C6—C7 | 123.5 (2) |
N1i—Cd1—N1 | 180.00 (4) | N5—C6—C7 | 122.2 (2) |
C1—N1—C4 | 116.8 (2) | C11—C7—C8 | 117.3 (2) |
C1—N1—Cd1 | 129.95 (16) | C11—C7—C6 | 122.3 (2) |
C4—N1—Cd1 | 113.06 (15) | C8—C7—C6 | 120.4 (2) |
C3—N2—C2 | 115.8 (2) | C9—C8—C7 | 119.8 (2) |
C5—N3—N4 | 105.73 (19) | C9—C8—H8 | 120.1 |
C5—N3—Cd1 | 113.59 (15) | C7—C8—H8 | 120.1 |
N4—N3—Cd1 | 140.64 (16) | C10—C9—C8 | 118.3 (3) |
C6—N4—N3 | 104.86 (19) | C10—C9—H9 | 120.9 |
C5—N5—C6 | 101.1 (2) | C8—C9—H9 | 120.9 |
C10—N6—C11 | 117.8 (2) | N6—C10—C9 | 123.7 (2) |
Cd1—O1—H1A | 112 (2) | N6—C10—H10 | 118.2 |
Cd1—O1—H1B | 115 (2) | C9—C10—H10 | 118.2 |
H1A—O1—H1B | 108 (2) | N6—C11—C7 | 123.1 (3) |
N1—C1—C2 | 121.9 (2) | N6—C11—H11 | 118.5 |
N1—C1—H1 | 119.1 | C7—C11—H11 | 118.5 |
C2—C1—H1 | 119.1 | ||
O1i—Cd1—N1—C1 | 88.8 (2) | Cd1—N1—C4—C5 | 7.6 (3) |
O1—Cd1—N1—C1 | −91.2 (2) | N2—C3—C4—N1 | −1.6 (4) |
N3—Cd1—N1—C1 | 179.3 (2) | N2—C3—C4—C5 | 177.7 (2) |
N3i—Cd1—N1—C1 | −0.7 (2) | N4—N3—C5—N5 | −0.3 (3) |
N1i—Cd1—N1—C1 | −49.9 (6) | Cd1—N3—C5—N5 | 177.79 (16) |
O1i—Cd1—N1—C4 | −97.06 (17) | N4—N3—C5—C4 | 179.0 (2) |
O1—Cd1—N1—C4 | 82.94 (17) | Cd1—N3—C5—C4 | −2.9 (3) |
N3—Cd1—N1—C4 | −6.62 (16) | C6—N5—C5—N3 | 0.3 (3) |
N3i—Cd1—N1—C4 | 173.38 (16) | C6—N5—C5—C4 | −179.0 (2) |
N1i—Cd1—N1—C4 | 124.2 (4) | N1—C4—C5—N3 | −3.4 (3) |
O1i—Cd1—N3—C5 | 97.31 (17) | C3—C4—C5—N3 | 177.4 (2) |
O1—Cd1—N3—C5 | −82.69 (17) | N1—C4—C5—N5 | 175.8 (2) |
N3i—Cd1—N3—C5 | −54 (63) | C3—C4—C5—N5 | −3.5 (4) |
N1i—Cd1—N3—C5 | −175.14 (16) | N3—N4—C6—N5 | 0.0 (3) |
N1—Cd1—N3—C5 | 4.86 (16) | N3—N4—C6—C7 | 178.2 (2) |
O1i—Cd1—N3—N4 | −85.7 (3) | C5—N5—C6—N4 | −0.2 (3) |
O1—Cd1—N3—N4 | 94.3 (3) | C5—N5—C6—C7 | −178.4 (2) |
N3i—Cd1—N3—N4 | 123 (62) | N4—C6—C7—C11 | 8.4 (4) |
N1i—Cd1—N3—N4 | 1.9 (3) | N5—C6—C7—C11 | −173.5 (2) |
N1—Cd1—N3—N4 | −178.1 (3) | N4—C6—C7—C8 | −170.8 (2) |
C5—N3—N4—C6 | 0.1 (3) | N5—C6—C7—C8 | 7.2 (4) |
Cd1—N3—N4—C6 | −177.05 (19) | C11—C7—C8—C9 | −1.5 (4) |
C4—N1—C1—C2 | −0.1 (4) | C6—C7—C8—C9 | 177.7 (2) |
Cd1—N1—C1—C2 | 173.81 (19) | C7—C8—C9—C10 | −0.4 (4) |
C3—N2—C2—C1 | 2.1 (4) | C11—N6—C10—C9 | −0.3 (4) |
N1—C1—C2—N2 | −1.9 (4) | C8—C9—C10—N6 | 1.3 (4) |
C2—N2—C3—C4 | −0.4 (4) | C10—N6—C11—C7 | −1.8 (4) |
C1—N1—C4—C3 | 1.8 (3) | C8—C7—C11—N6 | 2.7 (4) |
Cd1—N1—C4—C3 | −173.18 (19) | C6—C7—C11—N6 | −176.5 (2) |
C1—N1—C4—C5 | −177.5 (2) |
Symmetry code: (i) −x, −y+2, −z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1A···N6ii | 0.85 (2) | 1.95 (2) | 2.751 (3) | 157 (3) |
O1—H1B···N4iii | 0.86 (2) | 1.91 (2) | 2.763 (3) | 173 (3) |
Symmetry codes: (ii) x−1, y+1, z; (iii) −x, −y+1, −z. |
Experimental details
Crystal data | |
Chemical formula | [Cd(C11H7N6)2(H2O)2] |
Mr | 594.88 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 296 |
a, b, c (Å) | 8.640 (5), 5.684 (3), 23.157 (13) |
β (°) | 99.102 (6) |
V (Å3) | 1122.9 (11) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 1.02 |
Crystal size (mm) | 0.24 × 0.21 × 0.20 |
Data collection | |
Diffractometer | Bruker SMART CCD |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.782, 0.815 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 11387, 2571, 2251 |
Rint | 0.057 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.032, 0.081, 1.09 |
No. of reflections | 2571 |
No. of parameters | 175 |
No. of restraints | 3 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.38, −0.82 |
Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1A···N6i | 0.850 (17) | 1.949 (18) | 2.751 (3) | 157 (3) |
O1—H1B···N4ii | 0.859 (17) | 1.909 (17) | 2.763 (3) | 173 (3) |
Symmetry codes: (i) x−1, y+1, z; (ii) −x, −y+1, −z. |
References
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Much effort has been focused on the design and controlled synthesis of metal-organic frameworks or coordination polymers (Kitagawa et al., 2004). 1,2,4-triazole derivatives have received considerable attention, owing to the variety of their coordination modes, and structural features (Chen et al., 2006; Zhang et al., 2005). During the synthesis of polymeric complexes using 2-(5-(pyridin-3-yl)-4H-1,2,4-triazol-3-yl)pyrazine as bridging ligand and, to our surprise, the title monomeric Cd(II) complex was obtained. The title complex, is a crstallographically centrosymmetric mononuclear complex. The CdII cation, which is located on a centre of inversion, is six-coordinated by four N atoms from two chelating 2-(5-(pyridin-3-yl)-1,2,4-triazolido-3-yl)pyrazine ligands and two water O atoms, resulting into a distored octahedral geometry (Fig. 1). In the crystal, intermolecular O–H···N hydrogen bonding interactions (Table 2) link the title complex into a two-dimensional supramolecular network (Fig. 2).