supplementary materials


HTML versionpdf versioncif file3d viewstructure factorssupplementary materialsCIF check reportsimilar papers buy article online

Acta Cryst. (2007). E63, m1828-m1829    [ doi:10.1107/S1600536807025901 ]

Poly[[tetraaqua([mu]6-benzene-1,2,4,5-tetracarboxylato)dicobalt(II)] dihydrate]

Y.-H. Liu and M.-T. Ding

Abstract top

The asymmetric unit of the title coordination polymer, {[Co2(C10H2O8)(H2O)4]·2H2O}n, contains two crystallographically distinct CoII cations, located on inversion centers. Each CoII cation exists in an octahedral coordination environment formed by two water molecules and four carboxylate groups. The deprotonated benzene-1,2,4,5-tetracarboxylic acid ligand, with the center of the benzene ring located on an inversion center, bridges CoII cations to form a (3,4)-connected three-dimensional network that is topologically related to Pt3O4 (waserite). O-H...O hydrogen bonding between coordinated water molecules and carboxylate groups helps to stabilize the crystal structure. One water molecules is disordered over two positions, with almost equal occupancies.

Comment top

As shown in figure 1, a half of the Benzene-1,2,4,5-tetracarboxylic acid (H4btec) is observed in the crystallographic asymmetric unit with center of the benzene ring located on a crystallographic 1 position. The observation of symmetrical C═O bond lengths ranges from 1.250 (2) to 1.265 (3) Å indicates that all of the carboxyl groups of the H4btec are deprotonated to become the btec4− anion. The asymmetric unit of the title compound contains two crystallographic distinct CoII cations, located on crystallographic inversion centers with site occupation factor of 0.5. Each Co ion exists in an octahedral coordination environment (Table 1) formed by two water molecules and four carboxylate groups. The btec4− ligands bridges Co ions to form a three-dimensional metal-organic framework with one-dimensional channels in the [010] direction that are occupied by disordered guest water molecules and coordinated water molecules (Fig. 2). The formula of the compound is assigned to be [Co2(C10H2O8)(H2O)4·2H2O]n. A NiII analogue, and a CoII-btec coordination polymer with different contents of unit-cell packing were previously reported (Yang et al., 2003; Kumagai et al., 2002).

The network topology of the title compound is analyzed. The carbon atom of the carboxylate group serves as a simple three-connected node linking benzene ring and two Co ions. The benzene ring of the Benzene-1,2,4,5-tetracarboxylate ligand serves as a planar four-connected node. If coordinated water molecules are neglected, each Co ion also serves as a planar four-connected secondary building unit on the basis of four coordinated carboxylate groups. As a result, the title compound represents a new example of a (3,4)-connected net that is topologically related to Pt3O4 (waserite) (O'Keeffe et al., 2000; Wells, 1977).

The O—H···O hydroge bonding between coordinated water molecules and carboxyl groups helps to stabilize the crystal structure (Table 2).

Related literature top

For related structures, see: Kumagai et al. (2002); O'Keeffe et al. (2000); Wells (1977); Yang et al. (2003).

Experimental top

All reagents and solvents were used as obtained without further purification. CoCl2·6H2O (0.6 mmol), H4btec (0.5 mmol) and NaOH (1.0 mmol) were dissolved in 8 ml of distilled water. The mixture was sealed in a Teflon-lined stainless steel vessel and held at 383 K for 72 h. The vessel was gradually cooled to room temperature, and red crystals suitable for crystallographic analysis were obtained after 4 d.

Refinement top

The C-bound H atoms were placed in calculated positions (C—H = 0.93 Å) and refined in the riding-model approximation with Uiso(H) = 1.2Ueq(C). The H atoms of the coordinated water molecules were located in a difference Fourier map, and refined as riding model with O—H distances range from 0.82 to 0.85 Å, and with Uiso(H) = 1.5Ueq(O). The PLATON SQUEEZE procedure was used to treat regions of disordered guest molecules that could not be judiciously modeled in terms of atomic sites (Spek, 2003). The number of electrons thus located, 17 per unit cell, is assigned to two molecules of water solvent and is included in the formula, formula weight, calculated density, µ and F(000). There is difference between the reported and calculated values. Two largest residual densities located from the difference Fourier map separated by 1.93 Å are assigned to two disordered guest water molecules O31A and O31B. The refinement of relative site occupation factor leads to 0.53 and 0.47 for O31A and O31B, respectively. No attempt was made to locate hydrogen atoms of the disordered guest water molecules.

Computing details top

Data collection: XSCANS (Bruker, 1991); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997) and PLATON (Spek, 2003); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The asymmetric unit, expanded to show the complete coordination of the Co ions, with displacement ellipsoids drawn at the 50% probability level. Guest water molecules are omitted for clarity. (Symmetry codes are the same as geometric tables.)
[Figure 2] Fig. 2. Solid-state packing diagram of the three-dimensional framework.
[Figure 3] Fig. 3. Topological view of the Pt3O4 related (3,4)-connected net of the titel compound. (black sphere: C atom of carboxylate group; white sphere: center of btec4− ligand; grey sphere: Co ion.)
Poly[[tetraaqua(µ6-benzene-1,2,4,5-tetracarboxylato)dicobalt(II)] dihydrate] top
Crystal data top
[Co2(C10H2O8)(H2O)4]·2H2OZ = 2
Mr = 238.04F000 = 240
Triclinic, P1Dx = 1.966 Mg m−3
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 6.9362 (7) ÅCell parameters from 34 reflections
b = 7.4559 (6) Åθ = 5.6–12.8º
c = 8.2797 (7) ŵ = 2.14 mm−1
α = 90.342 (8)ºT = 298 (2) K
β = 109.848 (7)ºColumn, red
γ = 93.161 (7)º0.3 × 0.1 × 0.1 mm
V = 402.00 (6) Å3
Data collection top
Bruker P4
diffractometer		Rint = 0.028
Radiation source: sealed tubeθmax = 28.0º
Monochromator: graphiteθmin = 2.6º
T = 298(2) Kh = −9→1
2θ/ω scansk = −9→9
Absorption correction: ψ scan
(North et al., 1968)		l = −10→10
Tmin = 0.685, Tmax = 0.8113 standard reflections
2314 measured reflections every 24 reflections
1883 independent reflections intensity decay: 1.0%
1570 reflections with I > 2σ(I)
Refinement top
Refinement on F2H-atom parameters constrained
Least-squares matrix: full  w = 1/[σ2(Fo2) + (0.0533P)2 + 0.4406P]
where P = (Fo2 + 2Fc2)/3
R[F2 > 2σ(F2)] = 0.038(Δ/σ)max < 0.001
wR(F2) = 0.103Δρmax = 0.59 e Å−3
S = 1.05Δρmin = −0.77 e Å−3
1883 reflectionsExtinction correction: none
131 parameters
Crystal data top
[Co2(C10H2O8)(H2O)4]·2H2Oγ = 93.161 (7)º
Mr = 238.04V = 402.00 (6) Å3
Triclinic, P1Z = 2
a = 6.9362 (7) ÅMo Kα
b = 7.4559 (6) ŵ = 2.14 mm−1
c = 8.2797 (7) ÅT = 298 (2) K
α = 90.342 (8)º0.3 × 0.1 × 0.1 mm
β = 109.848 (7)º
Data collection top
Bruker P4
diffractometer		1570 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)		Rint = 0.028
Tmin = 0.685, Tmax = 0.8113 standard reflections
2314 measured reflections every 24 reflections
1883 independent reflections intensity decay: 1.0%
Refinement top
R[F2 > 2σ(F2)] = 0.038131 parameters
wR(F2) = 0.103H-atom parameters constrained
S = 1.05Δρmax = 0.59 e Å−3
1883 reflectionsΔρmin = −0.77 e Å−3
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Co1000.50.01624 (16)
Co20.50.50.50.01426 (16)
O10.1694 (3)0.2325 (3)0.6119 (3)0.0223 (4)
O20.4875 (3)0.3576 (3)0.7123 (3)0.0227 (4)
O30.2645 (3)−0.1283 (3)0.5378 (3)0.0268 (5)
O40.5570 (3)−0.2620 (3)0.6499 (2)0.0175 (4)
O210.0391 (4)0.0928 (4)0.2669 (3)0.0342 (6)
H21A0.1510.15380.28260.051*
H21B−0.03370.08860.16560.051*
O220.1793 (3)0.5155 (3)0.3953 (3)0.0265 (5)
H22A0.12240.60920.4040.04*
H22B0.14210.43970.45590.04*
O31A−0.0980 (8)0.2254 (8)−0.0766 (7)0.0469 (18)0.527 (8)
O31B−0.1415 (13)0.4510 (14)0.0178 (11)0.089 (4)0.473 (8)
C10.3523 (4)0.2411 (4)0.7155 (3)0.0155 (5)
C20.4193 (4)0.1081 (4)0.8574 (3)0.0150 (5)
C30.4640 (4)−0.0677 (4)0.8333 (3)0.0136 (5)
C40.4246 (4)−0.1563 (4)0.6596 (3)0.0145 (5)
C50.4549 (4)0.1741 (4)1.0238 (3)0.0163 (5)
H5A0.42410.29121.03990.02*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.0143 (3)0.0151 (3)0.0165 (3)0.00031 (19)0.0018 (2)−0.00175 (19)
Co20.0178 (3)0.0117 (3)0.0122 (2)−0.00056 (19)0.00392 (19)−0.00044 (18)
O10.0210 (10)0.0161 (10)0.0224 (10)−0.0007 (8)−0.0018 (8)0.0031 (8)
O20.0236 (11)0.0234 (11)0.0181 (9)−0.0065 (8)0.0042 (8)0.0048 (8)
O30.0238 (11)0.0343 (13)0.0170 (10)0.0117 (9)−0.0015 (8)−0.0091 (9)
O40.0177 (9)0.0163 (9)0.0170 (9)0.0033 (7)0.0035 (8)−0.0042 (7)
O210.0222 (11)0.0541 (16)0.0214 (11)−0.0087 (11)0.0028 (9)0.0053 (10)
O220.0219 (10)0.0225 (11)0.0346 (12)0.0025 (9)0.0088 (9)−0.0006 (9)
O31A0.038 (3)0.059 (4)0.040 (3)−0.001 (3)0.009 (2)0.004 (3)
O31B0.068 (6)0.092 (7)0.067 (5)−0.026 (5)−0.023 (4)0.007 (5)
C10.0210 (13)0.0127 (12)0.0120 (11)0.0002 (10)0.0048 (10)−0.0032 (9)
C20.0143 (12)0.0158 (12)0.0127 (11)−0.0026 (10)0.0025 (10)−0.0019 (9)
C30.0140 (12)0.0147 (12)0.0107 (11)−0.0023 (9)0.0032 (9)−0.0035 (9)
C40.0174 (12)0.0129 (12)0.0130 (11)−0.0008 (10)0.0052 (10)−0.0026 (9)
C50.0201 (13)0.0131 (12)0.0158 (12)0.0007 (10)0.0062 (10)−0.0018 (9)
Geometric parameters (Å, °) top
Co1—O12.065 (2)O3—C41.250 (3)
Co1—O1i2.065 (2)O4—C41.264 (3)
Co1—O3i2.046 (2)O4—Co2v2.0996 (19)
Co1—O32.046 (2)O21—H21A0.8472
Co1—O212.151 (2)O21—H21B0.8188
Co1—O21i2.151 (2)O22—H22A0.8359
Co2—O2ii2.083 (2)O22—H22B0.8447
Co2—O22.083 (2)C1—C21.508 (4)
Co2—O4iii2.0996 (19)C2—C31.392 (4)
Co2—O4iv2.0996 (19)C2—C51.395 (3)
Co2—O222.105 (2)C3—C5vi1.398 (4)
Co2—O22ii2.105 (2)C3—C41.511 (3)
O1—C11.265 (3)C5—C3vi1.398 (4)
O2—C11.250 (3)C5—H5A0.93
O3i—Co1—O3180.00 (12)O4iv—Co2—O22ii96.15 (8)
O3i—Co1—O189.65 (9)O22—Co2—O22ii180.0000 (10)
O3—Co1—O190.35 (9)C1—O1—Co1125.58 (19)
O3i—Co1—O1i90.35 (9)C1—O2—Co2126.83 (18)
O3—Co1—O1i89.65 (9)C4—O3—Co1137.74 (18)
O1—Co1—O1i180C4—O4—Co2v126.45 (17)
O3i—Co1—O2194.40 (10)Co1—O21—H21A113.9
O3—Co1—O2185.60 (10)Co1—O21—H21B134.3
O1—Co1—O2185.35 (9)H21A—O21—H21B111.6
O1i—Co1—O2194.65 (9)Co2—O22—H22A121.8
O3i—Co1—O21i85.60 (10)Co2—O22—H22B99.9
O3—Co1—O21i94.40 (10)H22A—O22—H22B105.4
O1—Co1—O21i94.65 (9)O2—C1—O1124.3 (3)
O1i—Co1—O21i85.35 (9)O2—C1—C2115.2 (2)
O21—Co1—O21i180.0000 (10)O1—C1—C2120.4 (2)
O2ii—Co2—O2180.0000 (10)C3—C2—C5119.3 (2)
O2ii—Co2—O4iii91.12 (8)C3—C2—C1124.0 (2)
O2—Co2—O4iii88.88 (8)C5—C2—C1116.4 (2)
O2ii—Co2—O4iv88.88 (8)C2—C3—C5vi119.4 (2)
O2—Co2—O4iv91.12 (8)C2—C3—C4124.2 (2)
O4iii—Co2—O4iv180C5vi—C3—C4116.4 (2)
O2ii—Co2—O2286.24 (9)O3—C4—O4123.9 (2)
O2—Co2—O2293.76 (9)O3—C4—C3119.9 (2)
O4iii—Co2—O2296.15 (8)O4—C4—C3116.1 (2)
O4iv—Co2—O2283.85 (8)C2—C5—C3vi121.4 (2)
O2ii—Co2—O22ii93.76 (9)C2—C5—H5A119.3
O2—Co2—O22ii86.24 (9)C3vi—C5—H5A119.3
O4iii—Co2—O22ii83.85 (8)
Symmetry codes: (i) −x, −y, −z+1; (ii) −x+1, −y+1, −z+1; (iii) x, y+1, z; (iv) −x+1, −y, −z+1; (v) x, y−1, z; (vi) −x+1, −y, −z+2.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O21—H21A···O4iv0.852.032.864 (3)169
O21—H21B···O31A0.822.172.876 (6)144
O22—H22A···O3iii0.842.252.848 (3)129
O22—H22B···O10.841.992.790 (3)157
Symmetry codes: (iv) −x+1, −y, −z+1; (iii) x, y+1, z.
Table 1
Selected geometric parameters (Å) top
Co1—O12.065 (2)Co2—O22.083 (2)
Co1—O32.046 (2)Co2—O4i2.0996 (19)
Co1—O212.151 (2)Co2—O222.105 (2)
Symmetry codes: (i) x, y+1, z.
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O21—H21A···O4ii0.852.032.864 (3)169
O21—H21B···O31A0.822.172.876 (6)144
O22—H22A···O3i0.842.252.848 (3)129
O22—H22B···O10.841.992.790 (3)157
Symmetry codes: (ii) −x+1, −y, −z+1; (i) x, y+1, z.
Acknowledgements top

The authors thank the National Science Council and Fu Jen Catholic University, Taiwan, for financial support.

references
References top

Bruker (1991). XSCANS. Version 4.27. Bruker AXS Inc., Madison, Wisconsin, USA.

Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565–?.

Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838.

Kumagai, H., Kepert, C. J. & Kurmoo, M. (2002). Inorg. Chem. 41, 3410–3422.

North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351–359.

O'Keeffe, M., Eddaoudi, M., Li, H., Reineke, T. & Yaghi, O. M. (2000). J. Solid State Chem. 152, 3–20.

Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.

Spek, A. L. (2003). J. Appl. Cryst. 36, 7–13.

Wells, A. F. (1977). Three-dimensional Nets and Polyhedra, pp. 91–103. New York: John Wiley & Sons Inc.

Yang, S.-Y., Long, L.-S., Huang, R.-B., Zheng, L.-S. & Ng, S. W. (2003). Acta Cryst. E59, m849–m850.