Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270104007851/de1237sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270104007851/de1237Isup2.hkl |
CCDC reference: 243569
The title compound was synthesized by the hydrothermal method from a mixture of benzene-1,2,4-tricarboxylic acid (1 mmol, 0.21 g), CoCl2·4H2O (1 mmol, 0.20 g), 1,10-phenanthroline (4 mmol, 0.72 g) and water (20 ml) in a 30 ml Teflon-lined stainless steel reactor. The solution was heated to 438 K for 5 d. After slow cooling of the reaction system to room temperature, red prism crystals of (I) were collected and washed with distilled water.
The water H atoms were refined subject to the restraint O—H = 0.82 (1) Å. The other H atoms were positioned geometrically and allowed to ride on their parent atoms at C—H distances of 0.93 Å, with Uiso(H) = 1.2Ueq(C).
Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP (Bruker, 2002); software used to prepare material for publication: SHELXL97.
[Co3(C9H3O6)2(C12H8N2)2H2O)2] | Z = 1 |
Mr = 987.46 | F(000) = 499 |
Triclinic, P1 | Dx = 1.795 Mg m−3 |
Hall symbol: -p1 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.7548 (12) Å | Cell parameters from 824 reflections |
b = 10.5687 (16) Å | θ = 2.3–21.4° |
c = 12.1678 (19) Å | µ = 1.43 mm−1 |
α = 88.238 (3)° | T = 273 K |
β = 77.760 (2)° | Prism, red |
γ = 69.813 (2)° | 0.20 × 0.18 × 0.10 mm |
V = 913.7 (2) Å3 |
Bruker APEX CCD area-detector diffractometer | 3281 independent reflections |
Radiation source: fine-focus sealed tube | 3089 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.029 |
ϕ and ω scans | θmax = 25.2°, θmin = 1.7° |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | h = −9→9 |
Tmin = 0.763, Tmax = 0.870 | k = −12→12 |
6767 measured reflections | l = −14→14 |
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)] = 0.066 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.147 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.22 | w = 1/[σ2(Fo2) + (0.0524P)2 + 2.7427P] where P = (Fo2 + 2Fc2)/3 |
3281 reflections | (Δ/σ)max < 0.001 |
287 parameters | Δρmax = 0.95 e Å−3 |
0 restraints | Δρmin = −0.78 e Å−3 |
[Co3(C9H3O6)2(C12H8N2)2H2O)2] | γ = 69.813 (2)° |
Mr = 987.46 | V = 913.7 (2) Å3 |
Triclinic, P1 | Z = 1 |
a = 7.7548 (12) Å | Mo Kα radiation |
b = 10.5687 (16) Å | µ = 1.43 mm−1 |
c = 12.1678 (19) Å | T = 273 K |
α = 88.238 (3)° | 0.20 × 0.18 × 0.10 mm |
β = 77.760 (2)° |
Bruker APEX CCD area-detector diffractometer | 3281 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | 3089 reflections with I > 2σ(I) |
Tmin = 0.763, Tmax = 0.870 | Rint = 0.029 |
6767 measured reflections |
R[F2 > 2σ(F2)] = 0.066 | 0 restraints |
wR(F2) = 0.147 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.22 | Δρmax = 0.95 e Å−3 |
3281 reflections | Δρmin = −0.78 e Å−3 |
287 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 | 0.18178 (9) | 0.77024 (7) | 0.78642 (5) | 0.0230 (2) | |
Co2 | −0.5000 | 1.0000 | 1.0000 | 0.0198 (2) | |
O1 | 0.3576 (5) | 0.7775 (4) | 0.8855 (3) | 0.0301 (8) | |
O2 | 0.3791 (5) | 0.8464 (3) | 1.0513 (3) | 0.0255 (8) | |
O3 | −0.0393 (5) | 0.8701 (4) | 0.9137 (3) | 0.0346 (9) | |
O4 | −0.2674 (4) | 0.8877 (3) | 1.0634 (3) | 0.0266 (8) | |
O5 | −0.1972 (5) | 0.4266 (4) | 1.1925 (3) | 0.0381 (9) | |
O6 | 0.0510 (6) | 0.3142 (4) | 1.2596 (4) | 0.0463 (11) | |
O7 | −0.3920 (5) | 0.9036 (4) | 0.8417 (3) | 0.0281 (8) | |
H7A | −0.2831 | 0.8534 | 0.8379 | 0.042* | |
H7 | −0.4486 | 0.8531 | 0.8334 | 0.042* | |
N1 | 0.4003 (6) | 0.7110 (4) | 0.6358 (4) | 0.0292 (10) | |
N2 | 0.1144 (6) | 0.9428 (4) | 0.6922 (3) | 0.0264 (9) | |
C1 | 0.5423 (8) | 0.5953 (6) | 0.6097 (5) | 0.0417 (14) | |
H1 | 0.5558 | 0.5281 | 0.6617 | 0.050* | |
C2 | 0.6733 (9) | 0.5704 (7) | 0.5066 (6) | 0.0539 (18) | |
H2 | 0.7740 | 0.4892 | 0.4920 | 0.065* | |
C3 | 0.6514 (9) | 0.6661 (7) | 0.4284 (6) | 0.0517 (18) | |
H3 | 0.7351 | 0.6494 | 0.3589 | 0.062* | |
C4 | 0.5041 (9) | 0.7891 (7) | 0.4522 (5) | 0.0423 (15) | |
C5 | 0.4700 (10) | 0.8974 (8) | 0.3765 (5) | 0.0489 (17) | |
H5 | 0.5475 | 0.8857 | 0.3051 | 0.059* | |
C6 | 0.3279 (10) | 1.0159 (7) | 0.4065 (5) | 0.0477 (16) | |
H6 | 0.3113 | 1.0851 | 0.3564 | 0.057* | |
C7 | 0.2034 (9) | 1.0363 (6) | 0.5136 (5) | 0.0371 (13) | |
C8 | 0.0528 (9) | 1.1576 (6) | 0.5500 (5) | 0.0447 (15) | |
H8 | 0.0297 | 1.2300 | 0.5032 | 0.054* | |
C9 | −0.0572 (9) | 1.1674 (6) | 0.6533 (5) | 0.0432 (15) | |
H9 | −0.1555 | 1.2476 | 0.6786 | 0.052* | |
C10 | −0.0246 (8) | 1.0583 (6) | 0.7224 (5) | 0.0363 (13) | |
H10 | −0.1041 | 1.0671 | 0.7929 | 0.044* | |
C11 | 0.2289 (8) | 0.9318 (5) | 0.5888 (4) | 0.0291 (11) | |
C12 | 0.3819 (8) | 0.8062 (6) | 0.5578 (4) | 0.0303 (12) | |
C13 | 0.3225 (6) | 0.7818 (5) | 0.9921 (4) | 0.0220 (10) | |
C14 | 0.2160 (6) | 0.6951 (5) | 1.0539 (4) | 0.0208 (10) | |
C15 | 0.0242 (6) | 0.7190 (5) | 1.0617 (4) | 0.0218 (10) | |
C16 | −0.0561 (7) | 0.6300 (5) | 1.1167 (4) | 0.0228 (10) | |
H16 | −0.1837 | 0.6472 | 1.1222 | 0.027* | |
C17 | 0.0479 (7) | 0.5166 (5) | 1.1635 (4) | 0.0247 (11) | |
C18 | 0.2376 (7) | 0.4946 (5) | 1.1587 (4) | 0.0280 (11) | |
H18 | 0.3093 | 0.4192 | 1.1909 | 0.034* | |
C19 | 0.3192 (7) | 0.5841 (5) | 1.1064 (4) | 0.0260 (11) | |
H19 | 0.4444 | 0.5702 | 1.1062 | 0.031* | |
C20 | −0.1014 (7) | 0.8355 (5) | 1.0094 (4) | 0.0232 (10) | |
C21 | −0.0376 (8) | 0.4127 (5) | 1.2095 (4) | 0.0323 (13) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Co1 | 0.0208 (4) | 0.0255 (4) | 0.0232 (4) | −0.0108 (3) | −0.0016 (3) | 0.0047 (3) |
Co2 | 0.0144 (5) | 0.0242 (5) | 0.0207 (5) | −0.0082 (4) | −0.0016 (3) | 0.0034 (4) |
O1 | 0.0269 (19) | 0.044 (2) | 0.0243 (19) | −0.0199 (17) | −0.0032 (15) | 0.0022 (16) |
O2 | 0.0244 (18) | 0.0288 (18) | 0.0283 (19) | −0.0152 (15) | −0.0068 (15) | 0.0042 (15) |
O3 | 0.0232 (19) | 0.041 (2) | 0.028 (2) | −0.0033 (16) | 0.0041 (15) | 0.0144 (16) |
O4 | 0.0139 (17) | 0.034 (2) | 0.0263 (18) | −0.0038 (15) | −0.0013 (14) | 0.0060 (15) |
O5 | 0.031 (2) | 0.032 (2) | 0.054 (3) | −0.0182 (17) | −0.0002 (18) | 0.0019 (18) |
O6 | 0.048 (3) | 0.035 (2) | 0.053 (3) | −0.015 (2) | −0.005 (2) | 0.019 (2) |
O7 | 0.0184 (17) | 0.038 (2) | 0.0250 (18) | −0.0106 (16) | 0.0023 (14) | −0.0014 (15) |
N1 | 0.025 (2) | 0.034 (2) | 0.028 (2) | −0.0099 (19) | −0.0022 (18) | −0.0035 (19) |
N2 | 0.030 (2) | 0.028 (2) | 0.023 (2) | −0.0148 (19) | −0.0025 (18) | 0.0061 (17) |
C1 | 0.032 (3) | 0.041 (3) | 0.048 (4) | −0.010 (3) | −0.004 (3) | −0.003 (3) |
C2 | 0.034 (4) | 0.046 (4) | 0.072 (5) | −0.005 (3) | −0.001 (3) | −0.015 (4) |
C3 | 0.041 (4) | 0.066 (5) | 0.043 (4) | −0.025 (3) | 0.015 (3) | −0.018 (3) |
C4 | 0.043 (4) | 0.060 (4) | 0.028 (3) | −0.029 (3) | 0.004 (3) | −0.007 (3) |
C5 | 0.057 (4) | 0.081 (5) | 0.020 (3) | −0.044 (4) | 0.001 (3) | 0.003 (3) |
C6 | 0.063 (4) | 0.065 (4) | 0.028 (3) | −0.039 (4) | −0.011 (3) | 0.018 (3) |
C7 | 0.048 (4) | 0.049 (4) | 0.027 (3) | −0.031 (3) | −0.012 (3) | 0.013 (3) |
C8 | 0.055 (4) | 0.039 (3) | 0.050 (4) | −0.022 (3) | −0.025 (3) | 0.020 (3) |
C9 | 0.043 (4) | 0.035 (3) | 0.049 (4) | −0.010 (3) | −0.011 (3) | 0.010 (3) |
C10 | 0.039 (3) | 0.033 (3) | 0.034 (3) | −0.010 (3) | −0.003 (2) | −0.001 (2) |
C11 | 0.032 (3) | 0.035 (3) | 0.026 (3) | −0.019 (2) | −0.005 (2) | 0.002 (2) |
C12 | 0.032 (3) | 0.044 (3) | 0.023 (3) | −0.025 (3) | −0.004 (2) | −0.001 (2) |
C13 | 0.013 (2) | 0.023 (2) | 0.029 (3) | −0.0047 (19) | −0.0039 (19) | 0.003 (2) |
C14 | 0.014 (2) | 0.025 (2) | 0.022 (2) | −0.0073 (19) | −0.0001 (18) | −0.0009 (19) |
C15 | 0.017 (2) | 0.026 (3) | 0.022 (2) | −0.010 (2) | −0.0007 (19) | −0.0002 (19) |
C16 | 0.017 (2) | 0.024 (2) | 0.027 (3) | −0.009 (2) | 0.0003 (19) | 0.000 (2) |
C17 | 0.023 (3) | 0.027 (3) | 0.024 (3) | −0.012 (2) | 0.002 (2) | −0.002 (2) |
C18 | 0.026 (3) | 0.022 (3) | 0.035 (3) | −0.007 (2) | −0.008 (2) | 0.004 (2) |
C19 | 0.016 (2) | 0.032 (3) | 0.031 (3) | −0.010 (2) | −0.002 (2) | 0.001 (2) |
C20 | 0.022 (3) | 0.026 (3) | 0.024 (3) | −0.012 (2) | −0.005 (2) | 0.001 (2) |
C21 | 0.040 (3) | 0.027 (3) | 0.025 (3) | −0.015 (2) | 0.007 (2) | −0.004 (2) |
Co1—O1 | 2.024 (3) | C3—C4 | 1.391 (9) |
Co1—O3 | 2.044 (4) | C3—H3 | 0.9300 |
Co1—O5i | 2.053 (4) | C4—C12 | 1.400 (7) |
Co1—N2 | 2.093 (4) | C4—C5 | 1.435 (9) |
Co1—N1 | 2.155 (4) | C5—C6 | 1.349 (10) |
Co2—O7 | 2.073 (3) | C5—H5 | 0.9300 |
Co2—O7ii | 2.073 (3) | C6—C7 | 1.420 (8) |
Co2—O4 | 2.077 (3) | C6—H6 | 0.9300 |
Co2—O4ii | 2.077 (3) | C7—C11 | 1.401 (8) |
Co2—O2iii | 2.155 (3) | C7—C8 | 1.409 (9) |
Co2—O2iv | 2.155 (3) | C8—C9 | 1.345 (9) |
O1—C13 | 1.266 (6) | C8—H8 | 0.9300 |
O2—C13 | 1.245 (6) | C9—C10 | 1.389 (8) |
O2—Co2v | 2.155 (3) | C9—H9 | 0.9300 |
O3—C20 | 1.257 (6) | C10—H10 | 0.9300 |
O4—C20 | 1.252 (6) | C11—C12 | 1.437 (8) |
O5—C21 | 1.256 (7) | C13—C14 | 1.518 (6) |
O5—Co1i | 2.053 (4) | C14—C19 | 1.396 (7) |
O6—C21 | 1.253 (7) | C14—C15 | 1.403 (7) |
O7—H7A | 0.8200 | C15—C16 | 1.382 (7) |
O7—H7 | 0.8200 | C15—C20 | 1.502 (7) |
N1—C1 | 1.325 (7) | C16—C17 | 1.377 (7) |
N1—C12 | 1.354 (7) | C16—H16 | 0.9300 |
N2—C10 | 1.319 (7) | C17—C18 | 1.396 (7) |
N2—C11 | 1.360 (7) | C17—C21 | 1.505 (7) |
C1—C2 | 1.404 (9) | C18—C19 | 1.380 (7) |
C1—H1 | 0.9300 | C18—H18 | 0.9300 |
C2—C3 | 1.360 (10) | C19—H19 | 0.9300 |
C2—H2 | 0.9300 | ||
O1—Co1—O3 | 88.42 (15) | C6—C5—C4 | 121.5 (6) |
O1—Co1—O5i | 98.79 (16) | C6—C5—H5 | 119.3 |
O3—Co1—O5i | 102.01 (15) | C4—C5—H5 | 119.3 |
O1—Co1—N2 | 110.90 (16) | C5—C6—C7 | 120.9 (6) |
O3—Co1—N2 | 89.05 (15) | C5—C6—H6 | 119.5 |
O5i—Co1—N2 | 148.64 (17) | C7—C6—H6 | 119.5 |
O1—Co1—N1 | 94.23 (15) | C11—C7—C8 | 117.0 (5) |
O3—Co1—N1 | 166.54 (16) | C11—C7—C6 | 119.4 (6) |
O5i—Co1—N1 | 90.65 (16) | C8—C7—C6 | 123.7 (6) |
N2—Co1—N1 | 77.67 (17) | C9—C8—C7 | 119.3 (5) |
O7—Co2—O7ii | 180 | C9—C8—H8 | 120.4 |
O7—Co2—O4 | 93.96 (14) | C7—C8—H8 | 120.4 |
O7ii—Co2—O4 | 86.04 (14) | C8—C9—C10 | 120.3 (6) |
O7—Co2—O4ii | 86.04 (14) | C8—C9—H9 | 119.8 |
O7ii—Co2—O4ii | 93.96 (14) | C10—C9—H9 | 119.8 |
O4—Co2—O4ii | 180 | N2—C10—C9 | 122.7 (5) |
O7—Co2—O2iii | 88.77 (13) | N2—C10—H10 | 118.6 |
O7ii—Co2—O2iii | 91.23 (13) | C9—C10—H10 | 118.6 |
O4—Co2—O2iii | 88.54 (13) | N2—C11—C7 | 122.9 (5) |
O4ii—Co2—O2iii | 91.46 (13) | N2—C11—C12 | 117.2 (5) |
O7—Co2—O2iv | 91.23 (13) | C7—C11—C12 | 119.8 (5) |
O7ii—Co2—O2iv | 88.77 (13) | N1—C12—C4 | 123.8 (5) |
O4—Co2—O2iv | 91.46 (13) | N1—C12—C11 | 116.5 (5) |
O4ii—Co2—O2iv | 88.54 (13) | C4—C12—C11 | 119.7 (5) |
O2iii—Co2—O2iv | 180 | O2—C13—O1 | 124.6 (4) |
C13—O1—Co1 | 126.4 (3) | O2—C13—C14 | 116.4 (4) |
C13—O2—Co2v | 127.8 (3) | O1—C13—C14 | 118.8 (4) |
C20—O3—Co1 | 132.1 (3) | C19—C14—C15 | 118.6 (4) |
C20—O4—Co2 | 127.1 (3) | C19—C14—C13 | 116.5 (4) |
C21—O5—Co1i | 97.3 (3) | C15—C14—C13 | 124.8 (4) |
Co2—O7—H7A | 109.5 | C16—C15—C14 | 119.7 (4) |
Co2—O7—H7 | 109.5 | C16—C15—C20 | 116.8 (4) |
H7A—O7—H7 | 104.5 | C14—C15—C20 | 123.5 (4) |
C1—N1—C12 | 117.5 (5) | C17—C16—C15 | 121.7 (4) |
C1—N1—Co1 | 128.9 (4) | C17—C16—H16 | 119.1 |
C12—N1—Co1 | 113.5 (3) | C15—C16—H16 | 119.1 |
C10—N2—C11 | 117.8 (5) | C16—C17—C18 | 118.7 (4) |
C10—N2—Co1 | 127.2 (4) | C16—C17—C21 | 120.3 (5) |
C11—N2—Co1 | 115.0 (3) | C18—C17—C21 | 120.8 (5) |
N1—C1—C2 | 122.5 (6) | C19—C18—C17 | 120.4 (5) |
N1—C1—H1 | 118.8 | C19—C18—H18 | 119.8 |
C2—C1—H1 | 118.8 | C17—C18—H18 | 119.8 |
C3—C2—C1 | 119.3 (6) | C18—C19—C14 | 120.8 (5) |
C3—C2—H2 | 120.4 | C18—C19—H19 | 119.6 |
C1—C2—H2 | 120.4 | C14—C19—H19 | 119.6 |
C2—C3—C4 | 120.1 (6) | O4—C20—O3 | 124.1 (5) |
C2—C3—H3 | 119.9 | O4—C20—C15 | 116.4 (4) |
C4—C3—H3 | 119.9 | O3—C20—C15 | 119.4 (4) |
C3—C4—C12 | 116.7 (6) | O6—C21—O5 | 121.9 (5) |
C3—C4—C5 | 124.6 (6) | O6—C21—C17 | 120.7 (5) |
C12—C4—C5 | 118.6 (6) | O5—C21—C17 | 117.4 (5) |
Symmetry codes: (i) −x, −y+1, −z+2; (ii) −x−1, −y+2, −z+2; (iii) x−1, y, z; (iv) −x, −y+2, −z+2; (v) x+1, y, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O7—H7···O1iii | 0.82 | 1.92 | 2.671 (5) | 152 |
O7—H7A···O3 | 0.82 | 2.33 | 2.950 (5) | 133 |
O7—H7A···O6i | 0.82 | 2.19 | 2.899 (5) | 144 |
Symmetry codes: (i) −x, −y+1, −z+2; (iii) x−1, y, z. |
Experimental details
Crystal data | |
Chemical formula | [Co3(C9H3O6)2(C12H8N2)2H2O)2] |
Mr | 987.46 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 273 |
a, b, c (Å) | 7.7548 (12), 10.5687 (16), 12.1678 (19) |
α, β, γ (°) | 88.238 (3), 77.760 (2), 69.813 (2) |
V (Å3) | 913.7 (2) |
Z | 1 |
Radiation type | Mo Kα |
µ (mm−1) | 1.43 |
Crystal size (mm) | 0.20 × 0.18 × 0.10 |
Data collection | |
Diffractometer | Bruker APEX CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2002) |
Tmin, Tmax | 0.763, 0.870 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6767, 3281, 3089 |
Rint | 0.029 |
(sin θ/λ)max (Å−1) | 0.599 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.066, 0.147, 1.22 |
No. of reflections | 3281 |
No. of parameters | 287 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.95, −0.78 |
Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), XP (Bruker, 2002), SHELXL97.
Co1—O1 | 2.024 (3) | Co1—N1 | 2.155 (4) |
Co1—O3 | 2.044 (4) | Co2—O7 | 2.073 (3) |
Co1—O5i | 2.053 (4) | Co2—O4 | 2.077 (3) |
Co1—N2 | 2.093 (4) | Co2—O2ii | 2.155 (3) |
O1—Co1—O3 | 88.42 (15) | O3—Co1—N1 | 166.54 (16) |
O1—Co1—O5i | 98.79 (16) | O5i—Co1—N1 | 90.65 (16) |
O3—Co1—O5i | 102.01 (15) | N2—Co1—N1 | 77.67 (17) |
O1—Co1—N2 | 110.90 (16) | O7—Co2—O4 | 93.96 (14) |
O3—Co1—N2 | 89.05 (15) | O7—Co2—O2ii | 88.77 (13) |
O5i—Co1—N2 | 148.64 (17) | O4—Co2—O2ii | 88.54 (13) |
O1—Co1—N1 | 94.23 (15) | O7—Co2—O2iii | 91.23 (13) |
Symmetry codes: (i) −x, −y+1, −z+2; (ii) x−1, y, z; (iii) −x, −y+2, −z+2. |
In recent years, versatile benzene-polycarboxylate ligands, such as benzene-1,3,5-tricarboxylic acid and benzene-1,2,4,5-tetracarboxylic acid, have been widely applied in the rational design and syntheses of metal-organic coordination polymers, owing to their high symmetry and the intriguing coordination modes of the carboxylate groups (Eddaoudi et al., 2000; Hu et al., 2003; Yaghi et al., 1996). However, little attention has been paid so far to benzene-1,2,4-tricarboxylic. It is of great interest to us that the carboxylate groups of benzene-polycarboxylate anions are capable of rotating in different directions with respect to the aromatic rings (Pisareva et al., 2003), and the introduction of terminal ligands into the carboxylate system can result in the formation of low-dimensional frameworks (Plater et al., 1999). Thus, we have selected the phen-btc system in order to extend this research. In the present compound, Co3(btc)2(phen)2(H2O)2, (I), two different kinds of independent CoII centres are bridged by btc to form a novel two-dimensional network. \sch
In the structure of (I) (Fig. 1), there are two different Co centres. The Co1 centre has a deformed trigonal-bipyramidal geometry completed by three carboxylate O atoms belonging to two btc ligands and two N atoms from a terminal phen molecule. The Co2 centre possesses a distorted octahedral geometry. The basal plane consists of two aqua O atoms and two carboxylate O atoms from two btc ligands. The two apical positions are filled by two carboxylate O atoms from two other btc ligands, the corresponding axial Co—O bond distances [2.155 (3) Å] being longer than the equatorial Co—O bond distances [2.073 (3)–2.077 (3) Å]. The separation of the independent Co centres [5.097 Å] is in agreement with that reported for a cobalt-2,2'-bipyridine-btc analogue (Plater et al., 2001).
The neighbouring 1,2-dicarboxylate groups of one btc ligand bridge two adjacent Co2 centres, and each Co2 centre is coordinated by four carboxylate O atoms from four different btc ligands, forming a novel kind of intersecting double-chain structure, with a Co—Co separation of 7.755 Å along the a axis. This is comparable with what was found in [Co2(C10H2O8)(C10H8N2)2(H2O)2]n (Xiao et al., 2004), in which the Co centres are also bridged by neighbouring 1,2-dicarboxylate groups and 4,5-dicarboxylate groups.
On the other hand, pairs of Co1 centres are bridged by two btc ligands to produce a binuclear unit, with a Co—Co separation of 8.406 Å, and these binuclear units are linked by btc bridges and Co2 centres to extend hybrid chains of Co1 and Co2 along the [101] direction.
Thus, as can be seen, three carboxylate groups of each btc ligand connect two Co1 centres and Co2 centres, respectively, by two different coordination modes, as a monodentate ligand with one Co centre and as a bidentate ligand with two Co centres. This is also comparable with what was found in a Fe—H2O-btc analogue (Riou-Cavellec et al., 2003). In this way, each btc ligand acts as a pentadentate bridge, linking the Co2 double-chain structures and the hybrid chains of Co1 and Co2 to yield a two-dimensional network, and this leads to the formation of very different kinds of voids (Fig. 2). Please check rewording.