metal-organic compounds
Hexaaquacobalt(II) 3,3′-dicarboxybiphenyl-4,4′-dicarboxylate
aSchool of Chemical Engineering and Technology, China University of Mining and Technology, Xuzhou, Jiangsu 221008, People's Republic of China, and bSchool of Chemical Science and Technology, Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, Yunnan University, Kunming 650091, People's Republic of China
*Correspondence e-mail: amudulin@gmail.com
In the 2O)6](C16H8O8), both the cation and anion are centrosymmetric. The Co cation displays a CoO6 octahedral geometry formed by six water molecules. In the anion, the two carboxyl groups are oriented at dihedral angles of 4.8 (5) and 10.4 (7)° with respect to the benzene ring. Very strong O—H⋯O hydrogen bonds between the protonated and deprotonated carboxylate groups occur. Neighbouring cations and anions are connected through O—H⋯O hydrogen bonds into a three-dimensional supramolecular structure.
of the title compound, [Co(HRelated literature
For related metal complexes with the biphenyl-3,3′,4,4′-tetracarboxylate ligand, see: Sun et al. (2009); Wang et al. (2005, 2006). For the structures containing the 4,4′-dicarboxybiphenyl-3,3′-dicarboxylate ligand, see: Kang et al. (2009a,b); Zhu et al. (2008).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (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/S1600536810028771/xu2789sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810028771/xu2789Isup2.hkl
A mixture of biphenyl-3,3',4,4'-tetracarboxylic acid (0.2 mmol) and Co(NO3)2.6H2O (0.4 mmol) in 12 ml methanol/water (8:3) sealed in a 25 ml Telflon-lined stainless steel autoclave was kept at 393 K for three days. Single crystals suitable for the X-ray experiment were obtained.
The carboxyl H atom was located in a difference map and refined isotropically. The H atoms of aromatic ring and water molecules were generated geometrically and were included in the
in the riding model approximation with C—H = 0.93 Å, Uiso(H)= 1.2 Ueq(C) and O—H = 0.96 Å, Uiso(H)= 1.5Ueq(O).Biphenyl–3,3',4,4'–tetracarboxylic acid have been used to construct high–dimensional supramolecular networks due to their versatile coordination modes and potential covalent or hydrogen bonding interactions with related parts in the assembly process (Sun et al. 2009; Wang et al. 2005) such as one-dimensional covalent zigzag chain coexist with one-dimensional hydrogen-bonded ladder (Wang et al. 2006). Here we reported a mononuclear complex, containing two ionic components of complex [Co(H2O)6](C16H18O8) (I) in which the two parts are connected via O—H···O hydrogen bonds forming a three-dimensional framework. The structure of the compound (I) consists of discrete ionic entities. A labeled diagram of the crystal [Co(H2O)6](C16H18O18) is shown in Fig. 1. In the cations, the metal atom is surrounded by six aqua ligands, exhibiting a slightly distorted octahedral stereochemistry. The cis/trans O—Co—O angles are nearly 90 °. The average Co—O distance for compound (I) is 2.077 Å. The anion 3,3',4,4'–biphenyltetralate contain inversion center. The mean plane was calculated throughout the six atoms of the benzene ring. Because of symmetric reason, the two benzene rings of the biphenyl ligand are coplanar. The carboxylate groups are almost coplanar with the benzene ring with the largest deviation of -0.205 (6) Å for O4. As expected, there are considerable hydrogen bonds in the structure. The bond distances and angles are listed in Table 2. A three–dimensional structure was formed via three kinds of hydrogen bonds between the coordinated water molecules and carboxyl groups which also help to consolide the crystal packing (Fig. 2).
For related metal complexes with the biphenyl-3,3',4,4'-tetracarboxylate ligand, see: Sun et al. (2009); Wang et al. (2005, 2006). For the structures containing the 4,4'-dicarboxybiphenyl-3,3'-dicarboxylate ligand, see: Kang et al. (2009a,b); Zhu et al. (2008).
Data collection: APEX2 (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).Fig. 1. The molecular structure of the title complex with the atom-numbering diagram. Ellipsoids were drawn at the 30% probability level. | |
Fig. 2. The packing diagram of (I). Hydrogen bonds are marked by dashed line. |
[Co(H2O)6](C16H8O8) | Z = 1 |
Mr = 495.25 | F(000) = 255 |
Triclinic, P1 | Dx = 1.694 Mg m−3 |
a = 6.5197 (14) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 7.9514 (17) Å | Cell parameters from 774 reflections |
c = 9.664 (2) Å | θ = 2.2–25.0° |
α = 76.339 (2)° | µ = 0.96 mm−1 |
β = 87.656 (2)° | T = 293 K |
γ = 86.221 (2)° | Block, pink |
V = 485.57 (18) Å3 | 0.23 × 0.19 × 0.12 mm |
Bruker APEXII CCD area-detector diffractometer | 1590 independent reflections |
Radiation source: fine-focus sealed tube | 1305 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.028 |
φ and ω scans | θmax = 25.0°, θmin = 2.2° |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | h = −7→7 |
Tmin = 0.804, Tmax = 0.895 | k = −9→9 |
2871 measured reflections | l = −11→10 |
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)] = 0.048 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.169 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | w = 1/[σ2(Fo2) + (0.1263P)2] where P = (Fo2 + 2Fc2)/3 |
1590 reflections | (Δ/σ)max < 0.001 |
146 parameters | Δρmax = 0.47 e Å−3 |
1 restraint | Δρmin = −0.43 e Å−3 |
[Co(H2O)6](C16H8O8) | γ = 86.221 (2)° |
Mr = 495.25 | V = 485.57 (18) Å3 |
Triclinic, P1 | Z = 1 |
a = 6.5197 (14) Å | Mo Kα radiation |
b = 7.9514 (17) Å | µ = 0.96 mm−1 |
c = 9.664 (2) Å | T = 293 K |
α = 76.339 (2)° | 0.23 × 0.19 × 0.12 mm |
β = 87.656 (2)° |
Bruker APEXII CCD area-detector diffractometer | 1590 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | 1305 reflections with I > 2σ(I) |
Tmin = 0.804, Tmax = 0.895 | Rint = 0.028 |
2871 measured reflections |
R[F2 > 2σ(F2)] = 0.048 | 1 restraint |
wR(F2) = 0.169 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | Δρmax = 0.47 e Å−3 |
1590 reflections | Δρmin = −0.43 e Å−3 |
146 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 | ||
Co1 | 1.0000 | 0.0000 | 0.5000 | 0.0281 (3) | |
O1 | 0.5091 (5) | 0.1808 (4) | 1.2457 (3) | 0.0408 (8) | |
O2 | 0.3077 (5) | 0.1278 (4) | 1.0880 (4) | 0.0396 (8) | |
O3 | 0.4682 (5) | 0.2634 (5) | 0.6417 (4) | 0.0494 (10) | |
O4 | 0.2791 (5) | 0.1755 (4) | 0.8356 (3) | 0.0417 (8) | |
O5 | 1.0135 (5) | −0.0174 (5) | 0.2911 (3) | 0.0434 (9) | |
H5B | 0.9751 | −0.1302 | 0.2858 | 0.065* | |
H5C | 1.1512 | −0.0002 | 0.2537 | 0.065* | |
O6 | 1.2248 (5) | 0.1707 (5) | 0.4594 (4) | 0.0444 (9) | |
H6A | 1.3079 | 0.1541 | 0.5419 | 0.067* | |
H6C | 1.3089 | 0.1508 | 0.3803 | 0.067* | |
O7 | 0.7843 (5) | 0.2081 (4) | 0.4461 (4) | 0.0441 (9) | |
H7A | 0.6763 | 0.1760 | 0.3946 | 0.066* | |
H7C | 0.7277 | 0.2372 | 0.5314 | 0.066* | |
C1 | 0.6112 (6) | 0.2899 (5) | 1.0027 (4) | 0.0255 (9) | |
C2 | 0.7719 (6) | 0.3637 (5) | 1.0551 (5) | 0.0257 (9) | |
H2B | 0.7823 | 0.3463 | 1.1532 | 0.031* | |
C3 | 0.9157 (6) | 0.4613 (5) | 0.9679 (5) | 0.0267 (9) | |
C4 | 0.8945 (7) | 0.4888 (6) | 0.8216 (5) | 0.0336 (10) | |
H4B | 0.9850 | 0.5580 | 0.7599 | 0.040* | |
C5 | 0.7413 (7) | 0.4147 (6) | 0.7674 (5) | 0.0358 (11) | |
H5A | 0.7335 | 0.4324 | 0.6691 | 0.043* | |
C6 | 0.5974 (6) | 0.3144 (5) | 0.8535 (5) | 0.0279 (9) | |
C7 | 0.4682 (6) | 0.1923 (5) | 1.1202 (5) | 0.0288 (10) | |
C8 | 0.4405 (7) | 0.2462 (6) | 0.7705 (5) | 0.0311 (10) | |
H2 | 0.293 (12) | 0.152 (9) | 0.999 (2) | 0.10 (3)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Co1 | 0.0215 (5) | 0.0511 (6) | 0.0143 (5) | −0.0164 (3) | 0.0002 (3) | −0.0092 (4) |
O1 | 0.0359 (17) | 0.070 (2) | 0.0193 (19) | −0.0237 (16) | 0.0020 (14) | −0.0103 (15) |
O2 | 0.0344 (17) | 0.062 (2) | 0.025 (2) | −0.0271 (15) | 0.0024 (15) | −0.0103 (16) |
O3 | 0.046 (2) | 0.087 (3) | 0.024 (2) | −0.0326 (19) | 0.0002 (16) | −0.0224 (17) |
O4 | 0.0316 (17) | 0.066 (2) | 0.032 (2) | −0.0238 (15) | 0.0005 (14) | −0.0133 (16) |
O5 | 0.0368 (18) | 0.077 (2) | 0.0222 (18) | −0.0290 (16) | 0.0048 (14) | −0.0167 (16) |
O6 | 0.0373 (18) | 0.074 (2) | 0.028 (2) | −0.0310 (16) | 0.0045 (15) | −0.0191 (16) |
O7 | 0.0361 (18) | 0.070 (2) | 0.0301 (19) | −0.0101 (16) | −0.0049 (15) | −0.0162 (16) |
C1 | 0.025 (2) | 0.032 (2) | 0.022 (2) | −0.0069 (16) | 0.0007 (17) | −0.0092 (17) |
C2 | 0.026 (2) | 0.034 (2) | 0.018 (2) | −0.0103 (17) | −0.0028 (17) | −0.0074 (17) |
C3 | 0.024 (2) | 0.033 (2) | 0.024 (2) | −0.0054 (17) | −0.0038 (18) | −0.0064 (17) |
C4 | 0.038 (2) | 0.045 (2) | 0.022 (2) | −0.023 (2) | −0.0027 (19) | −0.0090 (19) |
C5 | 0.042 (3) | 0.045 (3) | 0.024 (3) | −0.019 (2) | −0.002 (2) | −0.0117 (19) |
C6 | 0.024 (2) | 0.034 (2) | 0.029 (3) | −0.0078 (17) | −0.0020 (18) | −0.0103 (18) |
C7 | 0.028 (2) | 0.037 (2) | 0.026 (3) | −0.0109 (18) | 0.0014 (19) | −0.0126 (18) |
C8 | 0.029 (2) | 0.040 (2) | 0.029 (3) | −0.0118 (19) | −0.0047 (19) | −0.0137 (19) |
Co1—O5 | 2.054 (3) | O7—H7A | 0.9600 |
Co1—O5i | 2.054 (3) | O7—H7C | 0.9600 |
Co1—O6 | 2.027 (3) | C1—C2 | 1.401 (6) |
Co1—O6i | 2.027 (3) | C1—C6 | 1.415 (6) |
Co1—O7 | 2.082 (3) | C1—C7 | 1.534 (6) |
Co1—O7i | 2.082 (3) | C2—C3 | 1.383 (6) |
O1—C7 | 1.233 (5) | C2—H2B | 0.9300 |
O2—C7 | 1.276 (5) | C3—C4 | 1.390 (6) |
O2—H2 | 0.85 (2) | C3—C3ii | 1.516 (8) |
O3—C8 | 1.226 (6) | C4—C5 | 1.374 (6) |
O4—C8 | 1.295 (5) | C4—H4B | 0.9300 |
O5—H5B | 0.9600 | C5—C6 | 1.389 (6) |
O5—H5C | 0.9601 | C5—H5A | 0.9300 |
O6—H6A | 0.9600 | C6—C8 | 1.526 (6) |
O6—H6C | 0.9600 | ||
O6—Co1—O6i | 180.0 | C2—C1—C6 | 118.3 (4) |
O6—Co1—O5 | 90.40 (13) | C2—C1—C7 | 113.4 (4) |
O6i—Co1—O5 | 89.60 (13) | C6—C1—C7 | 128.3 (4) |
O6—Co1—O5i | 89.60 (13) | C3—C2—C1 | 123.2 (4) |
O6i—Co1—O5i | 90.40 (13) | C3—C2—H2B | 118.4 |
O5—Co1—O5i | 180.0 | C1—C2—H2B | 118.4 |
O6—Co1—O7 | 88.72 (14) | C2—C3—C4 | 117.5 (4) |
O6i—Co1—O7 | 91.28 (14) | C2—C3—C3ii | 120.3 (5) |
O5—Co1—O7 | 89.16 (14) | C4—C3—C3ii | 122.2 (5) |
O5i—Co1—O7 | 90.84 (14) | C5—C4—C3 | 120.6 (4) |
O6—Co1—O7i | 91.28 (14) | C5—C4—H4B | 119.7 |
O6i—Co1—O7i | 88.72 (14) | C3—C4—H4B | 119.7 |
O5—Co1—O7i | 90.83 (14) | C4—C5—C6 | 122.6 (4) |
O5i—Co1—O7i | 89.17 (14) | C4—C5—H5A | 118.7 |
O7—Co1—O7i | 180.000 (1) | C6—C5—H5A | 118.7 |
C7—O2—H2 | 111 (5) | C5—C6—C1 | 117.8 (4) |
Co1—O5—H5B | 109.3 | C5—C6—C8 | 113.7 (4) |
Co1—O5—H5C | 109.4 | C1—C6—C8 | 128.5 (4) |
H5B—O5—H5C | 109.5 | O1—C7—O2 | 120.9 (4) |
Co1—O6—H6A | 109.3 | O1—C7—C1 | 118.8 (4) |
Co1—O6—H6C | 109.1 | O2—C7—C1 | 120.3 (4) |
H6A—O6—H6C | 109.5 | O3—C8—O4 | 121.2 (4) |
Co1—O7—H7A | 109.1 | O3—C8—C6 | 118.9 (4) |
Co1—O7—H7C | 109.5 | O4—C8—C6 | 119.9 (4) |
H7A—O7—H7C | 109.5 | ||
C6—C1—C2—C3 | 0.9 (6) | C2—C1—C6—C8 | 179.1 (4) |
C7—C1—C2—C3 | −178.3 (4) | C7—C1—C6—C8 | −1.9 (7) |
C1—C2—C3—C4 | 1.4 (6) | C2—C1—C7—O1 | −2.9 (6) |
C1—C2—C3—C3ii | 179.4 (4) | C6—C1—C7—O1 | 178.0 (4) |
C2—C3—C4—C5 | −2.8 (7) | C2—C1—C7—O2 | 175.6 (4) |
C3ii—C3—C4—C5 | 179.2 (5) | C6—C1—C7—O2 | −3.5 (7) |
C3—C4—C5—C6 | 2.0 (7) | C5—C6—C8—O3 | 9.6 (6) |
C4—C5—C6—C1 | 0.3 (7) | C1—C6—C8—O3 | −171.2 (4) |
C4—C5—C6—C8 | 179.6 (4) | C5—C6—C8—O4 | −168.7 (4) |
C2—C1—C6—C5 | −1.8 (6) | C1—C6—C8—O4 | 10.4 (7) |
C7—C1—C6—C5 | 177.3 (4) |
Symmetry codes: (i) −x+2, −y, −z+1; (ii) −x+2, −y+1, −z+2. |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···O4 | 0.85 (2) | 1.55 (2) | 2.391 (5) | 173 (8) |
O5—H5B···O4iii | 0.96 | 2.17 | 2.820 (5) | 124 |
O5—H5C···O2iv | 0.96 | 1.97 | 2.789 (4) | 142 |
O6—H6A···O3v | 0.96 | 1.84 | 2.676 (4) | 144 |
O6—H6C···O1iv | 0.96 | 1.79 | 2.708 (4) | 159 |
O7—H7A···O1vi | 0.96 | 1.83 | 2.749 (5) | 159 |
O7—H7C···O3 | 0.96 | 1.99 | 2.822 (5) | 144 |
Symmetry codes: (iii) −x+1, −y, −z+1; (iv) x+1, y, z−1; (v) x+1, y, z; (vi) x, y, z−1. |
Experimental details
Crystal data | |
Chemical formula | [Co(H2O)6](C16H8O8) |
Mr | 495.25 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 293 |
a, b, c (Å) | 6.5197 (14), 7.9514 (17), 9.664 (2) |
α, β, γ (°) | 76.339 (2), 87.656 (2), 86.221 (2) |
V (Å3) | 485.57 (18) |
Z | 1 |
Radiation type | Mo Kα |
µ (mm−1) | 0.96 |
Crystal size (mm) | 0.23 × 0.19 × 0.12 |
Data collection | |
Diffractometer | Bruker APEXII CCD area-detector |
Absorption correction | Multi-scan (SADABS; Bruker, 2001) |
Tmin, Tmax | 0.804, 0.895 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2871, 1590, 1305 |
Rint | 0.028 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.048, 0.169, 1.00 |
No. of reflections | 1590 |
No. of parameters | 146 |
No. of restraints | 1 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.47, −0.43 |
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···O4 | 0.85 (2) | 1.55 (2) | 2.391 (5) | 173 (8) |
O5—H5B···O4i | 0.96 | 2.17 | 2.820 (5) | 124 |
O5—H5C···O2ii | 0.96 | 1.97 | 2.789 (4) | 142 |
O6—H6A···O3iii | 0.96 | 1.84 | 2.676 (4) | 144 |
O6—H6C···O1ii | 0.96 | 1.79 | 2.708 (4) | 159 |
O7—H7A···O1iv | 0.96 | 1.83 | 2.749 (5) | 159 |
O7—H7C···O3 | 0.96 | 1.99 | 2.822 (5) | 144 |
Symmetry codes: (i) −x+1, −y, −z+1; (ii) x+1, y, z−1; (iii) x+1, y, z; (iv) x, y, z−1. |
References
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Biphenyl–3,3',4,4'–tetracarboxylic acid have been used to construct high–dimensional supramolecular networks due to their versatile coordination modes and potential covalent or hydrogen bonding interactions with related parts in the assembly process (Sun et al. 2009; Wang et al. 2005) such as one-dimensional covalent zigzag chain coexist with one-dimensional hydrogen-bonded ladder (Wang et al. 2006). Here we reported a mononuclear complex, containing two ionic components of complex [Co(H2O)6](C16H18O8) (I) in which the two parts are connected via O—H···O hydrogen bonds forming a three-dimensional framework. The structure of the compound (I) consists of discrete ionic entities. A labeled diagram of the crystal [Co(H2O)6](C16H18O18) is shown in Fig. 1. In the cations, the metal atom is surrounded by six aqua ligands, exhibiting a slightly distorted octahedral stereochemistry. The cis/trans O—Co—O angles are nearly 90 °. The average Co—O distance for compound (I) is 2.077 Å. The anion 3,3',4,4'–biphenyltetralate contain inversion center. The mean plane was calculated throughout the six atoms of the benzene ring. Because of symmetric reason, the two benzene rings of the biphenyl ligand are coplanar. The carboxylate groups are almost coplanar with the benzene ring with the largest deviation of -0.205 (6) Å for O4. As expected, there are considerable hydrogen bonds in the structure. The bond distances and angles are listed in Table 2. A three–dimensional structure was formed via three kinds of hydrogen bonds between the coordinated water molecules and carboxyl groups which also help to consolide the crystal packing (Fig. 2).