Acta Cryst. (2007). E63, m1984 [ doi:10.1107/S1600536807030309 ]
![[mu]](/logos/entities/mu_rmgif.gif)
2-acetato-2-benzimidazolato-zinc(II)]The title compound, [Zn(C7H5N2)(C2H3O2)]n, was obtained unintentionally as the product of an attempted synthesis of a polycarboxylate-bridged network complex of zinc(II) using naphthalene-1,4,5,8-tetracarboxylic acid as the organic acid. The Zn atom is four-coordinated by two O atoms from two acetate (OAc) ligands and two N atoms from two different benzimidazole (bzim) ligands, resulting in a ZnN2O2 tetrahedron. The OAc and bzim ligands bridge the Zn atoms to form an infinite three-dimensional network.
Naphthalene-1,4,5,8-tetracarboxylic acid, benzimidazole and zinc acetate dihydrate were reacted in a molar ratio of 1:2:2. The mixture was stirred for 30 min, then the pH was adjusted to 8.0 with an aqueous solution of KOH (0.1 M). The mixture with a total volume of 21 ml was heated at 393 K for 5 d in a sealed 24 ml Teflon-lined stainless steel vessel under autogenous pressure. After the reaction mixture was slowly cooled to room temperature at a rate of 3 K h−1, pale yellow crystals of (I) were obtained.
The H atoms were positioned geometrically (C—H = 0.93–0.96 Å) and refined as riding with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C).
Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2001); software used to prepare material for publication: SHELXL97.
![[Figure 1]](./hb2445fig1thm.gif)
| Fig. 1. The asymmetric unit of (I) expanded to show the Zn coordination sphere. Displacement ellipsoids are drawn at the 30% probability level (arbitrary spheres for the H atoms). Symmetry codes: (i)1 − x, −1/2 + y, 3/2 − z, (ii)x, −1/2 − y, −1/2 + z. |
![[Figure 2]](./hb2445fig2thm.gif)
| Fig. 2. The packing diagrame for (I), showing the three-dimentional network structure. |
| [Zn(C7H5N2)(C2H3O2)] | F000 = 488 |
| Mr = 241.54 | Dx = 1.730 Mg m−3 |
| Monoclinic, P21/c | Mo Kα radiation λ = 0.71073 Å |
| Hall symbol: -P 2ybc | Cell parameters from 1655 reflections |
| a = 10.8177 (8) Å | θ = 6.0–26.1º |
| b = 9.8371 (7) Å | µ = 2.62 mm−1 |
| c = 8.8206 (6) Å | T = 292 (2) K |
| β = 98.938 (1)º | Block, pale yellow |
| V = 927.24 (11) Å3 | 0.47 × 0.35 × 0.12 mm |
| Z = 4 |
| Bruker SMART CCD diffractometer | 1825 independent reflections |
| Radiation source: fine-focus sealed tube | 1646 reflections with I > 2σ(I) |
| Monochromator: graphite | Rint = 0.020 |
| T = 293(2) K | θmax = 26.0º |
| ω scans | θmin = 2.8º |
| Absorption correction: multi-scan (SADABS; Bruker, 2001) | h = −13→13 |
| Tmin = 0.344, Tmax = 0.728 | k = −12→12 |
| 7653 measured reflections | l = −10→10 |
| 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)] = 0.023 | H-atom parameters constrained |
| wR(F2) = 0.063 | w = 1/[σ2(Fo2) + (0.0373P)2 + 0.3915P] where P = (Fo2 + 2Fc2)/3 |
| S = 1.04 | (Δ/σ)max = 0.001 |
| 1825 reflections | Δρmax = 0.33 e Å−3 |
| 127 parameters | Δρmin = −0.35 e Å−3 |
| Primary atom site location: structure-invariant direct methods | Extinction correction: none |
| [Zn(C7H5N2)(C2H3O2)] | V = 927.24 (11) Å3 |
| Mr = 241.54 | Z = 4 |
| Monoclinic, P21/c | Mo Kα |
| a = 10.8177 (8) Å | µ = 2.62 mm−1 |
| b = 9.8371 (7) Å | T = 292 (2) K |
| c = 8.8206 (6) Å | 0.47 × 0.35 × 0.12 mm |
| β = 98.938 (1)º |
| Bruker SMART CCD diffractometer | 1825 independent reflections |
| Absorption correction: multi-scan (SADABS; Bruker, 2001) | 1646 reflections with I > 2σ(I) |
| Tmin = 0.344, Tmax = 0.728 | Rint = 0.020 |
| 7653 measured reflections |
| R[F2 > 2σ(F2)] = 0.023 | 127 parameters |
| wR(F2) = 0.063 | H-atom parameters constrained |
| S = 1.04 | Δρmax = 0.33 e Å−3 |
| 1825 reflections | Δρmin = −0.35 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 | ||
| Zn1 | 0.35482 (2) | −0.27314 (2) | 0.65710 (2) | 0.02707 (10) | |
| O2 | 0.19757 (15) | −0.19050 (17) | 0.70465 (16) | 0.0377 (4) | |
| O1 | 0.31062 (14) | −0.18521 (17) | 0.93276 (16) | 0.0343 (3) | |
| N2 | 0.60329 (16) | 0.04848 (17) | 0.74407 (19) | 0.0291 (4) | |
| N1 | 0.48884 (16) | −0.13627 (18) | 0.66275 (19) | 0.0305 (4) | |
| C1 | 0.49555 (19) | −0.0187 (2) | 0.7378 (2) | 0.0306 (5) | |
| H1A | 0.4295 | 0.0145 | 0.7830 | 0.037* | |
| C3 | 0.6497 (2) | −0.2471 (2) | 0.5230 (3) | 0.0402 (5) | |
| H3A | 0.6023 | −0.3231 | 0.4889 | 0.048* | |
| C7 | 0.67473 (19) | −0.0327 (2) | 0.6622 (2) | 0.0285 (4) | |
| C6 | 0.7953 (2) | −0.0167 (2) | 0.6286 (3) | 0.0401 (5) | |
| H6A | 0.8439 | 0.0581 | 0.6642 | 0.048* | |
| C4 | 0.7678 (3) | −0.2287 (3) | 0.4880 (3) | 0.0506 (7) | |
| H4A | 0.8006 | −0.2930 | 0.4279 | 0.061* | |
| C2 | 0.60357 (19) | −0.1473 (2) | 0.6118 (2) | 0.0284 (4) | |
| C5 | 0.8401 (3) | −0.1151 (3) | 0.5410 (3) | 0.0533 (7) | |
| H5A | 0.9202 | −0.1062 | 0.5163 | 0.064* | |
| C8 | 0.2094 (2) | −0.1628 (2) | 0.8459 (2) | 0.0316 (5) | |
| C9 | 0.1003 (3) | −0.1018 (3) | 0.9057 (3) | 0.0608 (8) | |
| H9A | 0.0316 | −0.0923 | 0.8233 | 0.091* | |
| H9B | 0.1231 | −0.0141 | 0.9489 | 0.091* | |
| H9C | 0.0760 | −0.1598 | 0.9835 | 0.091* |
| U11 | U22 | U33 | U12 | U13 | U23 | |
| Zn1 | 0.02846 (16) | 0.02436 (15) | 0.02842 (15) | −0.00019 (9) | 0.00446 (10) | 0.00056 (9) |
| O2 | 0.0378 (9) | 0.0475 (9) | 0.0278 (8) | 0.0105 (7) | 0.0052 (6) | −0.0014 (7) |
| O1 | 0.0332 (8) | 0.0444 (9) | 0.0260 (7) | 0.0030 (7) | 0.0062 (6) | 0.0027 (6) |
| N2 | 0.0327 (9) | 0.0243 (9) | 0.0302 (9) | −0.0011 (7) | 0.0050 (7) | −0.0005 (7) |
| N1 | 0.0335 (10) | 0.0267 (9) | 0.0312 (9) | −0.0039 (7) | 0.0049 (7) | −0.0004 (7) |
| C1 | 0.0327 (11) | 0.0271 (11) | 0.0332 (11) | 0.0002 (9) | 0.0092 (9) | 0.0017 (8) |
| C3 | 0.0477 (15) | 0.0337 (12) | 0.0391 (13) | −0.0036 (10) | 0.0069 (11) | −0.0115 (9) |
| C7 | 0.0336 (11) | 0.0256 (10) | 0.0259 (10) | 0.0018 (8) | 0.0032 (8) | 0.0020 (8) |
| C6 | 0.0337 (12) | 0.0346 (12) | 0.0529 (14) | −0.0047 (10) | 0.0095 (10) | −0.0047 (10) |
| C4 | 0.0529 (16) | 0.0459 (15) | 0.0563 (16) | 0.0036 (12) | 0.0191 (13) | −0.0173 (12) |
| C2 | 0.0308 (11) | 0.0294 (11) | 0.0243 (10) | −0.0003 (8) | 0.0020 (8) | 0.0010 (8) |
| C5 | 0.0417 (14) | 0.0524 (17) | 0.0708 (18) | −0.0015 (12) | 0.0243 (13) | −0.0114 (14) |
| C8 | 0.0337 (12) | 0.0308 (11) | 0.0317 (11) | 0.0052 (9) | 0.0091 (9) | 0.0023 (9) |
| C9 | 0.0490 (16) | 0.089 (2) | 0.0461 (15) | 0.0285 (15) | 0.0146 (13) | −0.0058 (14) |
| Zn1—N1 | 1.9735 (17) | C3—C2 | 1.396 (3) |
| Zn1—N2i | 1.9802 (17) | C3—H3A | 0.9300 |
| Zn1—O2 | 1.9880 (15) | C7—C6 | 1.390 (3) |
| Zn1—O1ii | 2.0046 (14) | C7—C2 | 1.398 (3) |
| C8—O2 | 1.262 (3) | C6—C5 | 1.373 (3) |
| C8—O1 | 1.254 (3) | C6—H6A | 0.9300 |
| O1—Zn1iii | 2.0046 (14) | C4—C5 | 1.402 (4) |
| N2—C1 | 1.334 (3) | C4—H4A | 0.9300 |
| N2—C7 | 1.389 (3) | C5—H5A | 0.9300 |
| N2—Zn1iv | 1.9802 (17) | C8—C9 | 1.492 (3) |
| N1—C1 | 1.329 (3) | C9—H9A | 0.9600 |
| N1—C2 | 1.388 (3) | C9—H9B | 0.9600 |
| C1—H1A | 0.9300 | C9—H9C | 0.9600 |
| C3—C4 | 1.372 (4) | ||
| N1—Zn1—N2i | 118.46 (7) | C6—C7—C2 | 120.78 (19) |
| N1—Zn1—O2 | 111.41 (7) | C5—C6—C7 | 117.7 (2) |
| N2i—Zn1—O2 | 114.47 (7) | C5—C6—H6A | 121.2 |
| N1—Zn1—O1ii | 103.06 (7) | C7—C6—H6A | 121.2 |
| N2i—Zn1—O1ii | 104.87 (7) | C3—C4—C5 | 121.3 (2) |
| O2—Zn1—O1ii | 102.19 (6) | C3—C4—H4A | 119.3 |
| C8—O2—Zn1 | 109.73 (13) | C5—C4—H4A | 119.3 |
| C8—O1—Zn1iii | 133.67 (14) | N1—C2—C3 | 130.7 (2) |
| C1—N2—C7 | 104.28 (17) | N1—C2—C7 | 108.05 (18) |
| C1—N2—Zn1iv | 126.61 (14) | C3—C2—C7 | 121.2 (2) |
| C7—N2—Zn1iv | 129.08 (14) | C6—C5—C4 | 121.5 (2) |
| C1—N1—C2 | 104.28 (17) | C6—C5—H5A | 119.2 |
| C1—N1—Zn1 | 126.11 (15) | C4—C5—H5A | 119.2 |
| C2—N1—Zn1 | 128.97 (14) | O1—C8—O2 | 120.65 (19) |
| N1—C1—N2 | 115.59 (18) | O1—C8—C9 | 121.22 (19) |
| N1—C1—H1A | 122.2 | O2—C8—C9 | 118.1 (2) |
| N2—C1—H1A | 122.2 | C8—C9—H9A | 109.5 |
| C4—C3—C2 | 117.4 (2) | C8—C9—H9B | 109.5 |
| C4—C3—H3A | 121.3 | H9A—C9—H9B | 109.5 |
| C2—C3—H3A | 121.3 | C8—C9—H9C | 109.5 |
| N2—C7—C6 | 131.4 (2) | H9A—C9—H9C | 109.5 |
| N2—C7—C2 | 107.79 (18) | H9B—C9—H9C | 109.5 |
| Symmetry codes: (i) −x+1, y−1/2, −z+3/2; (ii) x, −y−1/2, z−1/2; (iii) x, −y−1/2, z+1/2; (iv) −x+1, y+1/2, −z+3/2. |
| Zn1—N1 | 1.9735 (17) | Zn1—O2 | 1.9880 (15) |
| Zn1—N2i | 1.9802 (17) | Zn1—O1ii | 2.0046 (14) |
| Symmetry codes: (i) −x+1, y−1/2, −z+3/2; (ii) x, −y−1/2, z−1/2. |
Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19 Is this the correct referencec?
Bruker (2001). SMART, SAINT, SADABS and SHELXTL. Bruker AXS Inc., Madison, Wisconsin, USA.
Eddaoudi, M., Kim, J., O'Keeffe, M. & Yaghi, O. M. (2002). J. Am. Chem. Soc. 124, 376–377.
Huang, X.-C., Zhang, J.-P. & Chen, X.-M. (2003). Chin. Sci. Bull. 48, 1491–1494.
Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.
Coordination polymers with a variety of supramolecular structures have been studied extensively because of their novel topologies and potential applications as functional materials (Eddaoudi et al., 2002). However, such compounds containing deprotonated benzimidazole (C7H5N2−, bzim) ligands have been rarely studied (Huang et al.,2003). We now report the title compound, (I), which is a new coordination polymer containing Zn2+ cations, bzim anions, and acetate (C2H3O2−) anions. These species combine in a 1:1:1 ratio, to esnsure charge balance.
In compond (I), the Zn atom is coordinated by two N atoms of two different bzim ligands and two O atoms from two different acetate anions, in a slightly distorted tetrahedral geometry (Fig. 1). The bond lengths (Table 1) are normal (Orpen et al., 1989). The C—O bond lengths of the acetate ion imply charge delocalization.
The acetic acid anion serves to link two Zn2+ ions together and the bzim species also acts as a bridge between two zinc ions. This connectivity results the coordination plymer in a three-dimensional network framwork structure (Fig. 2).