Acta Cryst. (2008). E64, m119 [ doi:10.1107/S1600536807063994 ]
In the title complex, [Cd(C3H2N3O2)2(H2O)2], the CdII atom is coordinated by two N and two O atoms from two deprotonated 1H-1,2,4-triazole-3-carboxylic acid ligands (TRIA) and two water molecules. The Cd atom is located on an inversion centre. In the crystal structure, molecules are linked together via O-H
O and N-HO hydrogen bonds, forming a three-dimensional network.
1H-1,2,4-triazole-3-carboxylic acid and CdCl2.2.5H2O were available commercially and were used without further purification. 1H-1,2,4-triazole-3-carboxylic acid (1 mmol, 113 mg) was dissolved in distilled water (15 ml) and CdCl2.2.5H2O (0.5 mmol, 114.2 mg) was added in distilled water (5 ml) with stirring at 323 K. The resulting colorless solution was allowed to react for 5 h and was then filtered. Colorless crystals suitable for X-ray analysis were obtained by slow evaporation of a water solution over a period of one month (yield 75%). Anal. Calcd (%) for C6H8CdN6O6 (Mr = 372.58): C, 19.34; H, 2.16; N, 22.56. Found (%): C, 19.28; H, 2.22; N, 22.49.
All the H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms with O—H, N—H and C—H distances of 0.85 Å, 0.86 Å and 0.93 Å, respectively, and Uiso(H) = 1.2Ueq(O), Uiso(H) = 1.2Ueq(N) and Uiso(H) = 1.2Ueq(C).
H atoms of the water molecules were located in a difference Fourier map and refined using a riding method. The highest peak in the difference map is 1.21 (1) Å from Cd1 and the largest hole is 0.60 (2) Å from Cd1.
Data collection: SMART (Siemens, 1996); cell refinement: SMART (Siemens, 1996); data reduction: SAINT (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL (Sheldrick, 1997b); software used to prepare material for publication: SHELXTL (Sheldrick, 1997b).
![[Figure 1]](./om2190fig1thm.gif)
| Fig. 1. The structure of the title compound showing 50% probability displacement ellipsoids and the atom-numbering scheme. Symmetry code: (i) -x, -y, -z. |
| [Cd(C3H2N3O2)2(H2O)2] | F000 = 364 |
| Mr = 372.58 | Dx = 2.169 Mg m−3 |
| Monoclinic, P21/c | Mo Kα radiation λ = 0.71073 Å |
| Hall symbol: -P 2ybc | Cell parameters from 2042 reflections |
| a = 9.2722 (16) Å | θ = 2.2–28.2º |
| b = 8.8318 (14) Å | µ = 1.95 mm−1 |
| c = 6.9714 (17) Å | T = 298 (1) K |
| β = 92.2300 (10)º | Prism, colorless |
| V = 570.46 (19) Å3 | 0.32 × 0.23 × 0.11 mm |
| Z = 2 |
| Bruker SMART CCD diffractometer | 1002 independent reflections |
| Radiation source: fine-focus sealed tube | 843 reflections with I > 2σ(I) |
| Monochromator: graphite | Rint = 0.023 |
| T = 298(1) K | θmax = 25.0º |
| φ and ω scans | θmin = 2.2º |
| Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −9→11 |
| Tmin = 0.574, Tmax = 0.814 | k = −10→10 |
| 2791 measured reflections | l = −8→7 |
| Refinement on F2 | Secondary atom site location: difference Fourier map |
| Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
| R[F2 > 2σ(F2)] = 0.027 | H-atom parameters constrained |
| wR(F2) = 0.077 | w = 1/[σ2(Fo2) + (0.0445P)2 + 0.5043P] where P = (Fo2 + 2Fc2)/3 |
| S = 1.09 | (Δ/σ)max < 0.001 |
| 1002 reflections | Δρmax = 1.21 e Å−3 |
| 88 parameters | Δρmin = −0.60 e Å−3 |
| Primary atom site location: structure-invariant direct methods | Extinction correction: none |
| [Cd(C3H2N3O2)2(H2O)2] | V = 570.46 (19) Å3 |
| Mr = 372.58 | Z = 2 |
| Monoclinic, P21/c | Mo Kα |
| a = 9.2722 (16) Å | µ = 1.95 mm−1 |
| b = 8.8318 (14) Å | T = 298 (1) K |
| c = 6.9714 (17) Å | 0.32 × 0.23 × 0.11 mm |
| β = 92.2300 (10)º |
| Bruker SMART CCD diffractometer | 1002 independent reflections |
| Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 843 reflections with I > 2σ(I) |
| Tmin = 0.574, Tmax = 0.814 | Rint = 0.023 |
| 2791 measured reflections |
| R[F2 > 2σ(F2)] = 0.027 | 88 parameters |
| wR(F2) = 0.077 | H-atom parameters constrained |
| S = 1.09 | Δρmax = 1.21 e Å−3 |
| 1002 reflections | Δρmin = −0.60 e Å−3 |
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 | 0.0000 | 0.0000 | 0.02817 (18) | |
| N1 | 0.2289 (4) | −0.0228 (3) | 0.1335 (5) | 0.0311 (8) | |
| N2 | 0.4348 (3) | 0.1039 (3) | 0.2024 (4) | 0.0311 (7) | |
| N3 | 0.4480 (3) | −0.0451 (4) | 0.2456 (5) | 0.0323 (7) | |
| H3 | 0.5255 | −0.0865 | 0.2927 | 0.039* | |
| O1 | 0.1027 (2) | 0.2387 (2) | −0.0103 (3) | 0.0293 (6) | |
| O2 | 0.2867 (2) | 0.3785 (2) | 0.1013 (4) | 0.0313 (6) | |
| O3 | −0.0921 (3) | 0.0865 (3) | 0.2849 (4) | 0.0409 (7) | |
| H3B | −0.0262 | 0.1228 | 0.3596 | 0.049* | |
| H3C | −0.1369 | 0.0171 | 0.3426 | 0.049* | |
| C1 | 0.2259 (3) | 0.2549 (4) | 0.0702 (5) | 0.0242 (7) | |
| C2 | 0.2995 (4) | 0.1123 (4) | 0.1356 (5) | 0.0253 (7) | |
| C3 | 0.3259 (4) | −0.1186 (4) | 0.2057 (6) | 0.0364 (9) | |
| H3A | 0.3110 | −0.2215 | 0.2255 | 0.044* |
| U11 | U22 | U33 | U12 | U13 | U23 | |
| Cd1 | 0.0187 (2) | 0.0234 (2) | 0.0416 (3) | −0.00318 (12) | −0.00840 (16) | −0.00195 (14) |
| N1 | 0.0245 (18) | 0.0259 (16) | 0.042 (2) | 0.0022 (12) | −0.0097 (14) | −0.0001 (13) |
| N2 | 0.0212 (15) | 0.0333 (16) | 0.0384 (17) | 0.0024 (13) | −0.0050 (13) | −0.0017 (14) |
| N3 | 0.0253 (17) | 0.0296 (15) | 0.0415 (19) | 0.0079 (14) | −0.0077 (14) | 0.0029 (14) |
| O1 | 0.0226 (12) | 0.0230 (12) | 0.0414 (15) | −0.0009 (9) | −0.0103 (10) | 0.0046 (10) |
| O2 | 0.0237 (13) | 0.0225 (12) | 0.0474 (15) | −0.0025 (10) | −0.0034 (11) | 0.0009 (10) |
| O3 | 0.0377 (15) | 0.0390 (15) | 0.0458 (16) | −0.0120 (12) | −0.0014 (12) | −0.0053 (12) |
| C1 | 0.0204 (17) | 0.0246 (17) | 0.0275 (18) | −0.0005 (14) | 0.0001 (13) | −0.0012 (14) |
| C2 | 0.0225 (18) | 0.0259 (17) | 0.0274 (18) | −0.0006 (14) | −0.0006 (13) | −0.0017 (14) |
| C3 | 0.032 (2) | 0.0286 (19) | 0.048 (2) | 0.0017 (17) | −0.0058 (17) | 0.0011 (17) |
| Cd1—N1 | 2.293 (3) | N2—N3 | 1.355 (4) |
| Cd1—N1i | 2.293 (3) | N3—C3 | 1.325 (5) |
| Cd1—O1i | 2.315 (2) | N3—H3 | 0.8600 |
| Cd1—O1 | 2.315 (2) | O1—C1 | 1.261 (4) |
| Cd1—O3i | 2.321 (3) | O2—C1 | 1.244 (4) |
| Cd1—O3 | 2.321 (3) | O3—H3B | 0.8500 |
| N1—C3 | 1.321 (5) | O3—H3C | 0.8500 |
| N1—C2 | 1.361 (4) | C1—C2 | 1.495 (5) |
| N2—C2 | 1.323 (4) | C3—H3A | 0.9300 |
| N1—Cd1—N1i | 180.00 (17) | C2—N2—N3 | 102.0 (3) |
| N1—Cd1—O1i | 106.43 (9) | C3—N3—N2 | 111.2 (3) |
| N1i—Cd1—O1i | 73.57 (9) | C3—N3—H3 | 124.4 |
| N1—Cd1—O1 | 73.57 (9) | N2—N3—H3 | 124.4 |
| N1i—Cd1—O1 | 106.43 (9) | C1—O1—Cd1 | 117.1 (2) |
| O1i—Cd1—O1 | 180.0 | Cd1—O3—H3B | 111.7 |
| N1—Cd1—O3i | 87.30 (11) | Cd1—O3—H3C | 111.8 |
| N1i—Cd1—O3i | 92.70 (11) | H3B—O3—H3C | 109.5 |
| O1i—Cd1—O3i | 83.82 (9) | O2—C1—O1 | 125.0 (3) |
| O1—Cd1—O3i | 96.18 (9) | O2—C1—C2 | 119.2 (3) |
| N1—Cd1—O3 | 92.70 (11) | O1—C1—C2 | 115.8 (3) |
| N1i—Cd1—O3 | 87.30 (11) | N2—C2—N1 | 113.8 (3) |
| O1i—Cd1—O3 | 96.18 (9) | N2—C2—C1 | 124.7 (3) |
| O1—Cd1—O3 | 83.82 (9) | N1—C2—C1 | 121.4 (3) |
| O3i—Cd1—O3 | 180.00 (12) | N1—C3—N3 | 109.2 (3) |
| C3—N1—C2 | 103.7 (3) | N1—C3—H3A | 125.4 |
| C3—N1—Cd1 | 144.8 (3) | N3—C3—H3A | 125.4 |
| C2—N1—Cd1 | 111.4 (2) | ||
| O1i—Cd1—N1—C3 | 4.2 (5) | Cd1—O1—C1—C2 | 9.1 (4) |
| O1—Cd1—N1—C3 | −175.8 (5) | N3—N2—C2—N1 | −0.5 (4) |
| O3i—Cd1—N1—C3 | −78.6 (5) | N3—N2—C2—C1 | 178.4 (3) |
| O3—Cd1—N1—C3 | 101.4 (5) | C3—N1—C2—N2 | 0.9 (5) |
| O1i—Cd1—N1—C2 | −179.7 (2) | Cd1—N1—C2—N2 | −176.8 (2) |
| O1—Cd1—N1—C2 | 0.3 (2) | C3—N1—C2—C1 | −178.1 (3) |
| O3i—Cd1—N1—C2 | 97.5 (3) | Cd1—N1—C2—C1 | 4.2 (4) |
| O3—Cd1—N1—C2 | −82.5 (3) | O2—C1—C2—N2 | −9.7 (5) |
| C2—N2—N3—C3 | −0.1 (4) | O1—C1—C2—N2 | 171.8 (3) |
| N1—Cd1—O1—C1 | −5.4 (2) | O2—C1—C2—N1 | 169.2 (3) |
| N1i—Cd1—O1—C1 | 174.6 (2) | O1—C1—C2—N1 | −9.3 (5) |
| O3i—Cd1—O1—C1 | −90.8 (2) | C2—N1—C3—N3 | −0.9 (5) |
| O3—Cd1—O1—C1 | 89.2 (2) | Cd1—N1—C3—N3 | 175.3 (3) |
| Cd1—O1—C1—O2 | −169.3 (3) | N2—N3—C3—N1 | 0.7 (5) |
| Symmetry codes: (i) −x, −y, −z. |
| D—H···A | D—H | H···A | D···A | D—H···A |
| O3—H3C···O2ii | 0.85 | 1.90 | 2.715 (3) | 159 |
| O3—H3B···O1iii | 0.85 | 1.91 | 2.736 (3) | 162 |
| N3—H3···O2iv | 0.86 | 1.89 | 2.728 (4) | 164 |
| Symmetry codes: (ii) −x, y−1/2, −z+1/2; (iii) x, −y+1/2, z+1/2; (iv) −x+1, y−1/2, −z+1/2. |
| D—H···A | D—H | H···A | D···A | D—H···A |
| O3—H3C···O2i | 0.85 | 1.90 | 2.715 (3) | 159 |
| O3—H3B···O1ii | 0.85 | 1.91 | 2.736 (3) | 162 |
| N3—H3···O2iii | 0.86 | 1.89 | 2.728 (4) | 164 |
| Symmetry codes: (i) −x, y−1/2, −z+1/2; (ii) x, −y+1/2, z+1/2; (iii) −x+1, y−1/2, −z+1/2. |
The authors thank the National Natural Science Foundation of China (20761002) for support. This research was sponsored by the Fund of the Talent Highland Research Program of Guangxi University (205121), the Science Foundation of the State Ethnic Affairs Commission (07GX05), the Development Foundation of Guangxi Research Institute of Chemical Industry and the Science Foundation of Guangxi University for Nationalities (0409032, 0409012, 0509ZD047).
Guo, X.-H. & Wang, Q.-X. (2005). Acta Cryst. E61, o3217–o3218.
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.
Sheldrick, G. M. (1997a). SHELXL97 andSHELXS97. University of Göttingen, Germany.
Sheldrick, G. M. (1997b). SHELXTL. Version 5.1. Bruker AXS, Inc., Madison, Wisconsin, USA.
Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.
Zhu, J., Yin, X.-H., Feng, Y., Zhao, K. & Su, Z.-X. (2007a). Acta Cryst. E63, m3167–?.
Zhu, J., Yin, X. H., Feng, Y., Zhao, K. & Zhang, S. S. (2007b). Acta Cryst. E63. In the press.. [Paper reference tk2217].
Recently, although the crystal structure of methyl 1H-1,2,4-triazole-3-carboxylate has been reported (Guo & Wang, 2005), metal complexes with triazole ligands have been rarely of interest for decades despite the biological importance of the triazole group. We have reported the crystal structures of two new copper(II) complexes diaquobis(1H-1,2,4-triazole-3-carboxylato)copper(II) and (1H-1,2,4-triazole-3-carboxylato)(1,10-phen)copper(II)chloride (Zhu, et al., 2007, 2008). As a further investigation, we report in this paper the crystal structure of a new cadmium(II) complex, diaquobis(1H- 1,2,4-triazole-3-carboxylato)cadmium(II).
As shown in Fig. 1, the title compound consists of a centrosymmetric mononuclear cadmium(II) complex cation. In the cation the Cd atom is six-coordinated by two N and two O atoms from two TRIA ligands and two O atoms from two water molecules. The CdII atom is in a slightly distorted octahedral environment. The Cd—O distances range from 2.315 (2) to 2.321 (3) Å, and the Cd—N bond length is 2.293 (3) Å, i.e. normal values. The C1—C2 bond length is 1.495 (5) Å, being in the normal C—C ranges in cadmium carboxylate complexes. The angles around CdII atom are from 73.57 (9) to linear. The TRIA molecule acts as a bidentate ligand.
In the title compound, the water molecules contribute to the formation of intermolecular hydrogen bonds involving carboxylate O atoms. Additional hydrogen bonds exist between the N—H groups of the triazole and carboxylate O atoms.