Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807050659/om2167sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807050659/om2167Isup2.hkl |
CCDC reference: 667206
The proton-transfer compound was prepared by a reaction between propane-1,3-diamine and benzene-1,2,4,5-tetracarboxylic acid [Aghabozorg, Ghadermazi et al., 2007]. Starting with a 1:1 molar ratio of the reactants in THF, a puffy white precipitate was obtained. By recrystallization in an aqueous solution, pale-yellow crystals were obtained. A solution of Co(NO3)2.6H2O (196 mg, 0.5 mmol) in water (15 ml) was added to an aqueous solution of (pnH2)2(btc).2H2O (253 mg, 1.0 mmol) in water (15 ml) in a 1:2 molar ratio. Colorless crystals suitable for X-ray characterization were obtained after a few days at room temperature.
The hydrogen atoms of the NH~3~ group and water molecules were found in the difference Fourier map. The H(C) atom positions were calculated. All hydrogen atoms were refined in isotropic approximation in riding model with with the Uĩso~(H) parameters equal to 1.2 U~eq~(Ci), 1.2 U~eq~(Oi) and 1.2 U~eq~(Ni) where U(Ci), U(Oi) and U(Ni) are respectively the equivalent thermal parameters of the carbon, oxygen and nitrigen atoms to which corresponding H atoms are bonded. Water molecule H(6 A)—O(6)—H(6B) has a total ocuppancy equal to 1/2 and is disordered by two positions, H(6B) atom is common for two positions. There is pseudo-symmetry in the crystal (space group Imma). However, the cation and water molecule are strongly disordered in the suggested Imma setting. One of the carbonyl O atoms is also disordered in Imma by two positions. Our attempt to solve the disordered structure in Imma group did not lead to acceptable R1 and wR2 values. The space group Ima2 is non-centrosymmetric so the Flack parameter can be calculated. The crystal is a racemic twin, so we used the TWIN instruction to refine the structure. In this case the Flack parameter is equal to the twin parameter of TWIN refinement (BASF). A total of 1206 Friedel pairs was measured.
We have reported cases in which proton transfer from benzene-1,2,4,5-tetracarboxylic acid (btcH4) to propane-1,3-diamine (pn), piperazine (pipz) and 1,10-phenanthroline (phen), resulted in the formation of novel self assembled (pnH2)2(btc).2H2O (Aghabozorg, Ghadermazi et al., 2007), (pipzH2)2(btc).6.2H2O (Aghabozorg, Manteghi, Ghadermazi 2007) and (phenH)4(btcH3)2(btcH2) (Aghabozorg, Ghadermazi & Attar Gharamaleki, 2006) systems, respectively. The resulting compounds, with some remaining sites as electron donors, can coordinate to metal ions (Aghabozorg, Ghasemikhah, Ghadermazi et al., 2006; Aghabozorg, Ghasemikhah, Soleimannejad et al., 2006). For the crystal structures of related complexes, see: Aghabozorg, Bahrami, et al., (2007); Aghabozorg, Zabihi et al., 2006; Aghabozorg, Attar Gharamaleki et al., 2007).
Here, we report a new polymeric compound obtained from reaction of (pnH2)2(btc).2H2O with cobalt(II) nitrate. The crystal structure of the title polymeric compound is shown in Fig. 1. The negative charge of the anionic complex is neutralized by dicationic propane-1,3-diammonium ions. The Co2+ atom is situated on a crystallographic twofold rotation axis.
Co2+ is six-coordinated by four (btc)4– groups and two coordinated water molecules, i.e. each (btc)4– fragments coordinates through one O atom of the (COO)- fragments, which also act as bridging ligands between other Co2+ ions. O5 and O5a atoms of two coordinated water molecules occupy the axial positions, while four O atoms of (btc)4– fragments form the equatorial plane. The axial bond is slightly longer than the equatorial bond lengths. The O5iii—Co1—O5 bond angle is slightly deviated from linearity. The coordination around Co2+ is distorted octahedral.
A considerable feature of the compound (Sharif et al., 2007) is the presence of C—H···π stacking interactions between C—H groups of (pnH2)2+ cations and aromatic rings of (btc)4– fragments (Fig. 2). The most important feature of the crystal structure is the presence of a large number of O—H···O, N—H···O and C—H···O hydrogen bonds between (pnH2)2+ and [Co(H2O)2(btc)]2– fragments and uncoordinated water molecules with D···A distances ranging from 2.679 (1) Å to 3.251 (2) Å. Hydrogen bonding, ion pairing, C—H···π stacking and van der Waals forces are effective in the stabilization of the crystal structure, resulting in the formation of an interesting supramolecular structure (Fig. 3).
For related literature, see: Aghabozorg, Attar Gharamaleki et al. (2007); Aghabozorg, Bahrami et al. (2007); Aghabozorg, Ghadermazi & Attar Gharamaleki (2006); Aghabozorg, Ghadermazi et al. (2007); Aghabozorg, Ghasemikhah, Ghadermazi et al. (2006); Aghabozorg, Ghasemikhah, Soleimannejad et al. (2006); Aghabozorg, Manteghi & Ghadermazi (2007); Aghabozorg, Zabihi et al. (2006); Sharif et al. (2007).
Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL Bruker, 2005); software used to prepare material for publication: SHELXTL Bruker, 2005).
(C3H12N2)[Co(C10H2O8)(H2O)2]·0.5H2O | F(000) = 888 |
Mr = 430.23 | Dx = 1.702 Mg m−3 |
Orthorhombic, Ima2 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: I 2 -2a | Cell parameters from 6735 reflections |
a = 16.4011 (3) Å | θ = 2.5–46.7° |
b = 7.1786 (1) Å | µ = 1.09 mm−1 |
c = 14.2586 (2) Å | T = 100 K |
V = 1678.76 (5) Å3 | Prism, colourless |
Z = 4 | 0.22 × 0.18 × 0.13 mm |
Bruker APEXII CCD diffractometer | 2526 independent reflections |
Radiation source: fine-focus sealed tube | 2479 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.026 |
ω scans | θmax = 30.0°, θmin = 3.1° |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | h = −23→23 |
Tmin = 0.796, Tmax = 0.872 | k = −10→10 |
19141 measured reflections | l = −20→20 |
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)] = 0.022 | H-atom parameters constrained |
wR(F2) = 0.066 | w = 1/[σ2(Fo2) + (0.05P)2 + P] where P = (Fo2 + 2Fc2)/3 |
S = 1.00 | (Δ/σ)max = 0.004 |
2526 reflections | Δρmax = 0.81 e Å−3 |
134 parameters | Δρmin = −0.35 e Å−3 |
1 restraint | Absolute structure: Flack (1983) |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.375 (11) |
(C3H12N2)[Co(C10H2O8)(H2O)2]·0.5H2O | V = 1678.76 (5) Å3 |
Mr = 430.23 | Z = 4 |
Orthorhombic, Ima2 | Mo Kα radiation |
a = 16.4011 (3) Å | µ = 1.09 mm−1 |
b = 7.1786 (1) Å | T = 100 K |
c = 14.2586 (2) Å | 0.22 × 0.18 × 0.13 mm |
Bruker APEXII CCD diffractometer | 2526 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | 2479 reflections with I > 2σ(I) |
Tmin = 0.796, Tmax = 0.872 | Rint = 0.026 |
19141 measured reflections |
R[F2 > 2σ(F2)] = 0.022 | H-atom parameters constrained |
wR(F2) = 0.066 | Δρmax = 0.81 e Å−3 |
S = 1.00 | Δρmin = −0.35 e Å−3 |
2526 reflections | Absolute structure: Flack (1983) |
134 parameters | Absolute structure parameter: 0.375 (11) |
1 restraint |
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 | Occ. (<1) | |
Co1 | 0.5000 | 0.5000 | 0.82749 (2) | 0.00585 (4) | |
O1 | 0.59187 (6) | 0.93889 (14) | 1.23336 (6) | 0.01174 (18) | |
O2 | 0.54019 (5) | 0.69011 (13) | 1.15830 (6) | 0.01297 (17) | |
O3 | 0.56026 (5) | 0.86184 (13) | 0.96344 (7) | 0.01294 (16) | |
O4 | 0.58410 (6) | 0.55896 (14) | 0.93363 (6) | 0.01095 (17) | |
C1 | 0.7500 | 0.8092 (3) | 1.17061 (12) | 0.0095 (3) | |
H1A | 0.7500 | 0.8483 | 1.2343 | 0.011* | |
C2 | 0.67589 (7) | 0.78092 (16) | 1.12452 (9) | 0.0090 (2) | |
C3 | 0.67626 (7) | 0.72442 (17) | 1.03074 (8) | 0.0083 (2) | |
C4 | 0.7500 | 0.6944 (2) | 0.98435 (12) | 0.0095 (3) | |
H4A | 0.7500 | 0.6535 | 0.9210 | 0.011* | |
C5 | 0.59580 (7) | 0.80529 (17) | 1.17606 (8) | 0.0093 (2) | |
C6 | 0.59980 (7) | 0.71361 (17) | 0.97228 (8) | 0.0090 (2) | |
O5 | 0.45721 (5) | 0.77721 (11) | 0.82396 (8) | 0.01252 (15) | |
H5B | 0.4770 | 0.8192 | 0.8781 | 0.015* | |
H5A | 0.4806 | 0.8255 | 0.7732 | 0.015* | |
N1 | 0.40163 (6) | 0.73402 (16) | 0.54638 (8) | 0.0136 (2) | |
H1B | 0.4460 | 0.7422 | 0.5844 | 0.020* | |
H1C | 0.4044 | 0.8241 | 0.5016 | 0.020* | |
H1D | 0.4006 | 0.6200 | 0.5185 | 0.020* | |
C7 | 0.32604 (8) | 0.75991 (19) | 0.60320 (9) | 0.0136 (2) | |
H7A | 0.3248 | 0.8881 | 0.6288 | 0.016* | |
H7B | 0.3264 | 0.6718 | 0.6566 | 0.016* | |
C8 | 0.2500 | 0.7265 (3) | 0.54340 (14) | 0.0133 (3) | |
H8A | 0.2500 | 0.5971 | 0.5195 | 0.016* | |
H8B | 0.2500 | 0.8123 | 0.4890 | 0.016* | |
O6 | 0.2991 (5) | 0.9781 (12) | 0.8219 (7) | 0.071 (2) | 0.25 |
H6A | 0.3333 | 0.8845 | 0.8105 | 0.085* | 0.25 |
H6B | 0.2500 | 0.9320 | 0.8101 | 0.085* | 0.50 |
U11 | U22 | U33 | U12 | U13 | U23 | |
Co1 | 0.00543 (8) | 0.00700 (8) | 0.00512 (8) | −0.00108 (6) | 0.000 | 0.000 |
O1 | 0.0107 (4) | 0.0125 (4) | 0.0120 (4) | −0.0006 (4) | 0.0035 (3) | −0.0034 (3) |
O2 | 0.0105 (4) | 0.0155 (4) | 0.0129 (4) | −0.0035 (3) | 0.0009 (3) | −0.0023 (3) |
O3 | 0.0122 (3) | 0.0118 (4) | 0.0149 (4) | 0.0024 (3) | −0.0036 (3) | −0.0017 (3) |
O4 | 0.0107 (4) | 0.0114 (4) | 0.0107 (4) | −0.0002 (3) | −0.0025 (3) | −0.0008 (3) |
C1 | 0.0094 (7) | 0.0114 (6) | 0.0077 (7) | 0.000 | 0.000 | −0.0018 (6) |
C2 | 0.0103 (5) | 0.0077 (5) | 0.0091 (5) | 0.0004 (4) | 0.0010 (4) | −0.0016 (4) |
C3 | 0.0061 (4) | 0.0094 (5) | 0.0095 (5) | 0.0000 (4) | 0.0000 (4) | −0.0007 (4) |
C4 | 0.0095 (7) | 0.0090 (6) | 0.0099 (8) | 0.000 | 0.000 | −0.0009 (6) |
C5 | 0.0084 (5) | 0.0106 (5) | 0.0089 (5) | 0.0006 (4) | 0.0000 (4) | 0.0009 (4) |
C6 | 0.0080 (4) | 0.0114 (5) | 0.0078 (5) | −0.0011 (4) | 0.0011 (4) | 0.0003 (4) |
O5 | 0.0144 (3) | 0.0129 (3) | 0.0103 (3) | 0.0005 (3) | −0.0004 (4) | 0.0000 (3) |
N1 | 0.0095 (4) | 0.0143 (5) | 0.0170 (5) | 0.0001 (4) | 0.0009 (4) | 0.0029 (4) |
C7 | 0.0121 (5) | 0.0122 (5) | 0.0166 (6) | 0.0004 (4) | 0.0004 (4) | 0.0010 (5) |
C8 | 0.0099 (6) | 0.0132 (7) | 0.0169 (7) | 0.000 | 0.000 | 0.0012 (6) |
O6 | 0.056 (3) | 0.120 (6) | 0.036 (3) | 0.056 (4) | 0.014 (4) | 0.001 (4) |
Co1—O1i | 2.0650 (9) | C4—H4A | 0.9500 |
Co1—O4 | 2.0910 (9) | O5—H5B | 0.8899 |
Co1—O5 | 2.1107 (8) | O5—H5A | 0.8901 |
O1—C5 | 1.2615 (16) | N1—C7 | 1.4926 (16) |
O1—Co1ii | 2.0650 (9) | N1—H1B | 0.9100 |
O2—C5 | 1.2569 (15) | N1—H1C | 0.9100 |
O3—C6 | 1.2525 (15) | N1—H1D | 0.9100 |
O4—C6 | 1.2659 (16) | C7—C8 | 1.5297 (17) |
C1—C2 | 1.3967 (15) | C7—H7A | 0.9900 |
C1—C2iii | 1.3967 (15) | C7—H7B | 0.9900 |
C1—H1A | 0.9500 | C8—C7iv | 1.5297 (17) |
C2—C3 | 1.3973 (14) | C8—H8A | 0.9900 |
C2—C5 | 1.5153 (17) | C8—H8B | 0.9900 |
C3—C4 | 1.3952 (14) | O6—O6iv | 1.612 (15) |
C3—C6 | 1.5077 (17) | O6—H6A | 0.8900 |
C4—C3iii | 1.3952 (14) | O6—H6B | 0.8873 |
O1i—Co1—O1v | 98.92 (5) | O1—C5—C2 | 116.50 (11) |
O1i—Co1—O4 | 174.14 (4) | O3—C6—O4 | 126.57 (11) |
O1v—Co1—O4 | 86.91 (3) | O3—C6—C3 | 116.27 (11) |
O4—Co1—O4vi | 87.26 (5) | O4—C6—C3 | 117.07 (11) |
O1i—Co1—O5vi | 91.54 (4) | Co1—O5—H5B | 100.2 |
O1v—Co1—O5vi | 86.68 (4) | Co1—O5—H5A | 104.1 |
O4—Co1—O5vi | 89.36 (4) | H5B—O5—H5A | 114.6 |
O4vi—Co1—O5vi | 92.62 (4) | C7—N1—H1B | 109.5 |
O1v—Co1—O5 | 91.54 (4) | C7—N1—H1C | 109.5 |
O4—Co1—O5 | 92.62 (4) | H1B—N1—H1C | 109.5 |
O4vi—Co1—O5 | 89.36 (4) | C7—N1—H1D | 109.5 |
O5vi—Co1—O5 | 177.26 (6) | H1B—N1—H1D | 109.5 |
C5—O1—Co1ii | 128.29 (8) | H1C—N1—H1D | 109.5 |
C6—O4—Co1 | 128.82 (8) | N1—C7—C8 | 110.80 (11) |
C2—C1—C2iii | 120.99 (16) | N1—C7—H7A | 109.5 |
C2—C1—H1A | 119.5 | C8—C7—H7A | 109.5 |
C2iii—C1—H1A | 119.5 | N1—C7—H7B | 109.5 |
C1—C2—C3 | 119.25 (13) | C8—C7—H7B | 109.5 |
C1—C2—C5 | 120.62 (11) | H7A—C7—H7B | 108.1 |
C3—C2—C5 | 120.10 (12) | C7—C8—C7iv | 109.24 (15) |
C4—C3—C2 | 120.15 (13) | C7—C8—H8A | 109.8 |
C4—C3—C6 | 116.80 (11) | C7iv—C8—H8A | 109.8 |
C2—C3—C6 | 122.71 (12) | C7—C8—H8B | 109.8 |
C3—C4—C3iii | 120.18 (15) | C7iv—C8—H8B | 109.8 |
C3—C4—H4A | 119.9 | H8A—C8—H8B | 108.3 |
C3iii—C4—H4A | 119.9 | O6iv—O6—H6A | 129.1 |
O2—C5—O1 | 126.41 (11) | H6A—O6—H6B | 104.9 |
O2—C5—C2 | 117.09 (11) | ||
O1v—Co1—O4—C6 | 88.68 (11) | Co1ii—O1—C5—C2 | −172.14 (8) |
O4vi—Co1—O4—C6 | −91.95 (11) | C1—C2—C5—O2 | −140.38 (14) |
O5vi—Co1—O4—C6 | 175.39 (11) | C3—C2—C5—O2 | 37.76 (15) |
O5—Co1—O4—C6 | −2.72 (11) | C1—C2—C5—O1 | 39.04 (18) |
C2iii—C1—C2—C3 | −0.4 (2) | C3—C2—C5—O1 | −142.82 (11) |
C2iii—C1—C2—C5 | 177.80 (11) | Co1—O4—C6—O3 | 10.12 (19) |
C1—C2—C3—C4 | 0.84 (16) | Co1—O4—C6—C3 | −166.26 (8) |
C5—C2—C3—C4 | −177.32 (13) | C4—C3—C6—O3 | −114.56 (14) |
C1—C2—C3—C6 | −172.23 (14) | C2—C3—C6—O3 | 58.73 (15) |
C5—C2—C3—C6 | 9.60 (15) | C4—C3—C6—O4 | 62.21 (17) |
C2—C3—C4—C3iii | −1.3 (2) | C2—C3—C6—O4 | −124.50 (12) |
C6—C3—C4—C3iii | 172.13 (10) | N1—C7—C8—C7iv | −178.35 (9) |
Co1ii—O1—C5—O2 | 7.22 (19) |
Symmetry codes: (i) −x+1, y−1/2, z−1/2; (ii) x, −y+3/2, z+1/2; (iii) −x+3/2, y, z; (iv) −x+1/2, y, z; (v) x, −y+3/2, z−1/2; (vi) −x+1, −y+1, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O5—H5B···O3 | 0.89 | 1.85 | 2.680 (1) | 153 |
O5—H5A···O2v | 0.89 | 1.91 | 2.737 (1) | 154 |
N1—H1B···O2v | 0.91 | 1.93 | 2.831 (1) | 168 |
N1—H1C···O4vii | 0.91 | 1.95 | 2.843 (2) | 166 |
N1—H1D···O3i | 0.91 | 2.11 | 2.988 (2) | 161 |
C7—H7B···Cgviii | 0.99 | 2.98 | 3.767 (2) | 137 |
C8—H8B···Cgix | 0.99 | 2.61 | 3.439 (2) | 141 |
Symmetry codes: (i) −x+1, y−1/2, z−1/2; (v) x, −y+3/2, z−1/2; (vii) −x+1, y+1/2, z−1/2; (viii) x+1/2, y−1/2, z+1/2; (ix) x+1/2, y+1/2, z+1/2. |
Experimental details
Crystal data | |
Chemical formula | (C3H12N2)[Co(C10H2O8)(H2O)2]·0.5H2O |
Mr | 430.23 |
Crystal system, space group | Orthorhombic, Ima2 |
Temperature (K) | 100 |
a, b, c (Å) | 16.4011 (3), 7.1786 (1), 14.2586 (2) |
V (Å3) | 1678.76 (5) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 1.09 |
Crystal size (mm) | 0.22 × 0.18 × 0.13 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2005) |
Tmin, Tmax | 0.796, 0.872 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 19141, 2526, 2479 |
Rint | 0.026 |
(sin θ/λ)max (Å−1) | 0.703 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.022, 0.066, 1.00 |
No. of reflections | 2526 |
No. of parameters | 134 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.81, −0.35 |
Absolute structure | Flack (1983) |
Absolute structure parameter | 0.375 (11) |
Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL Bruker, 2005).
Co1—O1i | 2.0650 (9) | Co1—O5 | 2.1107 (8) |
Co1—O4 | 2.0910 (9) | ||
O1i—Co1—O4 | 174.14 (4) | O5ii—Co1—O5 | 177.26 (6) |
Symmetry codes: (i) −x+1, y−1/2, z−1/2; (ii) −x+1, −y+1, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O5—H5B···O3 | 0.89 | 1.85 | 2.680 (1) | 153 |
O5—H5A···O2iii | 0.89 | 1.91 | 2.737 (1) | 154 |
N1—H1B···O2iii | 0.91 | 1.93 | 2.831 (1) | 168 |
N1—H1C···O4iv | 0.91 | 1.95 | 2.843 (2) | 166 |
N1—H1D···O3i | 0.91 | 2.11 | 2.988 (2) | 161 |
C7—H7B···Cgv | 0.99 | 2.98 | 3.767 (2) | 137 |
C8—H8B···Cgvi | 0.99 | 2.61 | 3.439 (2) | 141 |
Symmetry codes: (i) −x+1, y−1/2, z−1/2; (iii) x, −y+3/2, z−1/2; (iv) −x+1, y+1/2, z−1/2; (v) x+1/2, y−1/2, z+1/2; (vi) x+1/2, y+1/2, z+1/2. |
We have reported cases in which proton transfer from benzene-1,2,4,5-tetracarboxylic acid (btcH4) to propane-1,3-diamine (pn), piperazine (pipz) and 1,10-phenanthroline (phen), resulted in the formation of novel self assembled (pnH2)2(btc).2H2O (Aghabozorg, Ghadermazi et al., 2007), (pipzH2)2(btc).6.2H2O (Aghabozorg, Manteghi, Ghadermazi 2007) and (phenH)4(btcH3)2(btcH2) (Aghabozorg, Ghadermazi & Attar Gharamaleki, 2006) systems, respectively. The resulting compounds, with some remaining sites as electron donors, can coordinate to metal ions (Aghabozorg, Ghasemikhah, Ghadermazi et al., 2006; Aghabozorg, Ghasemikhah, Soleimannejad et al., 2006). For the crystal structures of related complexes, see: Aghabozorg, Bahrami, et al., (2007); Aghabozorg, Zabihi et al., 2006; Aghabozorg, Attar Gharamaleki et al., 2007).
Here, we report a new polymeric compound obtained from reaction of (pnH2)2(btc).2H2O with cobalt(II) nitrate. The crystal structure of the title polymeric compound is shown in Fig. 1. The negative charge of the anionic complex is neutralized by dicationic propane-1,3-diammonium ions. The Co2+ atom is situated on a crystallographic twofold rotation axis.
Co2+ is six-coordinated by four (btc)4– groups and two coordinated water molecules, i.e. each (btc)4– fragments coordinates through one O atom of the (COO)- fragments, which also act as bridging ligands between other Co2+ ions. O5 and O5a atoms of two coordinated water molecules occupy the axial positions, while four O atoms of (btc)4– fragments form the equatorial plane. The axial bond is slightly longer than the equatorial bond lengths. The O5iii—Co1—O5 bond angle is slightly deviated from linearity. The coordination around Co2+ is distorted octahedral.
A considerable feature of the compound (Sharif et al., 2007) is the presence of C—H···π stacking interactions between C—H groups of (pnH2)2+ cations and aromatic rings of (btc)4– fragments (Fig. 2). The most important feature of the crystal structure is the presence of a large number of O—H···O, N—H···O and C—H···O hydrogen bonds between (pnH2)2+ and [Co(H2O)2(btc)]2– fragments and uncoordinated water molecules with D···A distances ranging from 2.679 (1) Å to 3.251 (2) Å. Hydrogen bonding, ion pairing, C—H···π stacking and van der Waals forces are effective in the stabilization of the crystal structure, resulting in the formation of an interesting supramolecular structure (Fig. 3).