metal-organic compounds
Bis(3,5-dinitrobenzoato-κO1)tetramethanolcobalt(II)
aDepartment of Chemistry, North Bengal University, Darjeeling, West Bengal 734 430, India, and bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: edward.tiekink@gmail.com
The CoII atom (site symmetry ) in the title complex, [Co(C7H3N2O6)2(CH3OH)4], exists within an octahedral O6 donor set defined by two O-monodentate 3,5-dinitrobenzoate anions and four methanol O atoms. An intramolecular Om—H⋯Oc (m = methanol and c = carbonyl) hydrogen bond leads to the formation of an S(6) ring. In the crystal, centrosymmetrically related molecules associate via further Om—H⋯Oc hydrogen bonds, leading to linear supramolecular chains propagating along the a-axis direction.
Related literature
For the structures of related complexes, see: Tahir et al. (1996); Yang et al. (2000); Jin et al. (2008). For a description of the Cambridge Structural Database, see: Allen (2002).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2008); cell SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).
Supporting information
10.1107/S1600536810007580/hb5347sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536810007580/hb5347Isup2.hkl
All chemicals purchased from commercial sources (AR/GR grade) were used without further purification. The crystalline sodium salt of 3,5-dinitrobenzoic acid was prepared by neutralising 3,5-dinitrobenzoic acid (1.00 g, 4.70 mmol) by NaOH (1.88 g, 4.70 mmol) in water. On concentration the solution yielded the sodium salt (1). To a purple solution of CoCl2.6H2O (0.50 g, 2.10 mmol) in water (15 ml) was added, with stirring, a solution of (1) (0.98 g, 4.20 mmol) in a mixture of water (3 ml) and methanol (140 ml) when the colour of the mixture turned pink. The solution was then heated under reflux for 6 h. Pink prisms of (I) were obtained from the filtrate after 25 days on slow evaporation.
Carbon-bound H-atoms were placed in calculated positions (C—H 0.93 to 0.96 Å) and were included in the
in the riding model approximation, with Uiso(H) set to 1.2 to 1.5Uequiv(C). The methanol H-atoms were located in a difference Fourier map, and were refined with a distance restraint of O–H 0.85±0.01 Å; their Uiso values were freely refinedData collection: APEX2 (Bruker, 2008); cell
SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).[Co(C7H3N2O6)2(CH4O)4] | Z = 1 |
Mr = 609.33 | F(000) = 313 |
Triclinic, P1 | Dx = 1.543 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 6.4068 (8) Å | Cell parameters from 1592 reflections |
b = 8.7660 (11) Å | θ = 2.4–22.8° |
c = 12.1603 (16) Å | µ = 0.74 mm−1 |
α = 90.411 (2)° | T = 293 K |
β = 100.407 (2)° | Prism, pink |
γ = 102.214 (2)° | 0.35 × 0.30 × 0.05 mm |
V = 655.77 (14) Å3 |
Bruker SMART APEX diffractometer | 2999 independent reflections |
Radiation source: fine-focus sealed tube | 2388 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.028 |
ω scans | θmax = 27.5°, θmin = 1.7° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −8→8 |
Tmin = 0.669, Tmax = 0.746 | k = −11→11 |
6372 measured reflections | l = −15→15 |
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)] = 0.043 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.110 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0522P)2 + 0.1427P] where P = (Fo2 + 2Fc2)/3 |
2999 reflections | (Δ/σ)max = 0.001 |
188 parameters | Δρmax = 0.38 e Å−3 |
2 restraints | Δρmin = −0.30 e Å−3 |
[Co(C7H3N2O6)2(CH4O)4] | γ = 102.214 (2)° |
Mr = 609.33 | V = 655.77 (14) Å3 |
Triclinic, P1 | Z = 1 |
a = 6.4068 (8) Å | Mo Kα radiation |
b = 8.7660 (11) Å | µ = 0.74 mm−1 |
c = 12.1603 (16) Å | T = 293 K |
α = 90.411 (2)° | 0.35 × 0.30 × 0.05 mm |
β = 100.407 (2)° |
Bruker SMART APEX diffractometer | 2999 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2388 reflections with I > 2σ(I) |
Tmin = 0.669, Tmax = 0.746 | Rint = 0.028 |
6372 measured reflections |
R[F2 > 2σ(F2)] = 0.043 | 2 restraints |
wR(F2) = 0.110 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.38 e Å−3 |
2999 reflections | Δρmin = −0.30 e Å−3 |
188 parameters |
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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 | ||
Co | 0.5000 | 0.5000 | 0.5000 | 0.03530 (16) | |
O1 | 0.6891 (3) | 0.3924 (2) | 0.61732 (14) | 0.0514 (5) | |
O2 | 0.8795 (3) | 0.2811 (2) | 0.51696 (14) | 0.0471 (4) | |
O3 | 1.4087 (5) | 0.0083 (4) | 0.7142 (2) | 0.1213 (12) | |
O4 | 1.4957 (5) | 0.0210 (4) | 0.8875 (2) | 0.1234 (12) | |
O5 | 1.0327 (5) | 0.2304 (4) | 1.1038 (2) | 0.1159 (11) | |
O6 | 0.8093 (6) | 0.3608 (4) | 1.0193 (2) | 0.1090 (10) | |
O7 | 0.3342 (3) | 0.5533 (2) | 0.62522 (14) | 0.0458 (4) | |
H7O | 0.255 (4) | 0.614 (3) | 0.595 (2) | 0.075 (11)* | |
O8 | 0.2673 (3) | 0.2953 (2) | 0.46261 (18) | 0.0550 (5) | |
H8O | 0.145 (3) | 0.291 (4) | 0.481 (3) | 0.075 (10)* | |
N1 | 1.3845 (5) | 0.0471 (3) | 0.8033 (2) | 0.0710 (8) | |
N2 | 0.9450 (5) | 0.2836 (4) | 1.0197 (2) | 0.0775 (8) | |
C1 | 0.8312 (4) | 0.3181 (3) | 0.60687 (19) | 0.0379 (5) | |
C2 | 0.9496 (4) | 0.2659 (3) | 0.7142 (2) | 0.0383 (5) | |
C3 | 1.1103 (4) | 0.1830 (3) | 0.7114 (2) | 0.0420 (6) | |
H3 | 1.1468 | 0.1592 | 0.6436 | 0.050* | |
C4 | 1.2149 (4) | 0.1366 (3) | 0.8100 (2) | 0.0498 (6) | |
C5 | 1.1687 (5) | 0.1679 (3) | 0.9125 (2) | 0.0547 (7) | |
H5 | 1.2420 | 0.1356 | 0.9783 | 0.066* | |
C6 | 1.0075 (5) | 0.2500 (3) | 0.9125 (2) | 0.0525 (7) | |
C7 | 0.8985 (4) | 0.2998 (3) | 0.8158 (2) | 0.0468 (6) | |
H7 | 0.7914 | 0.3558 | 0.8191 | 0.056* | |
C8 | 0.4162 (5) | 0.5914 (4) | 0.7407 (2) | 0.0604 (8) | |
H8A | 0.3034 | 0.6156 | 0.7755 | 0.091* | |
H8B | 0.5356 | 0.6803 | 0.7491 | 0.091* | |
H8C | 0.4652 | 0.5041 | 0.7755 | 0.091* | |
C9 | 0.2797 (6) | 0.1460 (3) | 0.4244 (3) | 0.0787 (11) | |
H9A | 0.2018 | 0.1255 | 0.3487 | 0.118* | |
H9B | 0.2166 | 0.0686 | 0.4712 | 0.118* | |
H9C | 0.4292 | 0.1422 | 0.4271 | 0.118* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Co | 0.0357 (3) | 0.0419 (3) | 0.0339 (3) | 0.01829 (19) | 0.00943 (18) | 0.00124 (18) |
O1 | 0.0558 (11) | 0.0699 (12) | 0.0409 (10) | 0.0385 (10) | 0.0118 (8) | 0.0069 (8) |
O2 | 0.0428 (9) | 0.0662 (12) | 0.0387 (9) | 0.0257 (8) | 0.0080 (7) | 0.0001 (8) |
O3 | 0.151 (3) | 0.177 (3) | 0.083 (2) | 0.133 (3) | 0.0311 (18) | 0.0207 (19) |
O4 | 0.125 (2) | 0.193 (3) | 0.086 (2) | 0.117 (2) | 0.0082 (17) | 0.044 (2) |
O5 | 0.157 (3) | 0.168 (3) | 0.0389 (14) | 0.074 (2) | 0.0149 (15) | 0.0175 (16) |
O6 | 0.167 (3) | 0.132 (2) | 0.0629 (16) | 0.085 (2) | 0.0510 (17) | 0.0109 (15) |
O7 | 0.0501 (11) | 0.0574 (11) | 0.0379 (9) | 0.0259 (9) | 0.0125 (8) | 0.0023 (8) |
O8 | 0.0428 (11) | 0.0497 (11) | 0.0767 (13) | 0.0086 (9) | 0.0242 (10) | −0.0125 (9) |
N1 | 0.0722 (17) | 0.088 (2) | 0.0672 (18) | 0.0498 (16) | 0.0113 (14) | 0.0207 (15) |
N2 | 0.109 (2) | 0.086 (2) | 0.0466 (16) | 0.0382 (18) | 0.0211 (15) | 0.0030 (14) |
C1 | 0.0346 (12) | 0.0411 (13) | 0.0400 (13) | 0.0133 (10) | 0.0064 (10) | 0.0019 (10) |
C2 | 0.0375 (12) | 0.0384 (12) | 0.0398 (13) | 0.0105 (10) | 0.0064 (10) | 0.0032 (10) |
C3 | 0.0429 (13) | 0.0482 (14) | 0.0377 (13) | 0.0173 (11) | 0.0060 (10) | 0.0027 (10) |
C4 | 0.0463 (14) | 0.0495 (15) | 0.0560 (16) | 0.0200 (12) | 0.0046 (12) | 0.0081 (12) |
C5 | 0.0603 (17) | 0.0605 (17) | 0.0422 (15) | 0.0184 (14) | −0.0003 (12) | 0.0095 (12) |
C6 | 0.0645 (17) | 0.0566 (16) | 0.0380 (14) | 0.0176 (14) | 0.0080 (12) | 0.0011 (12) |
C7 | 0.0509 (15) | 0.0488 (14) | 0.0458 (14) | 0.0205 (12) | 0.0107 (11) | 0.0031 (11) |
C8 | 0.078 (2) | 0.0658 (19) | 0.0409 (15) | 0.0215 (16) | 0.0146 (14) | −0.0014 (13) |
C9 | 0.084 (2) | 0.0532 (18) | 0.104 (3) | 0.0050 (17) | 0.044 (2) | −0.0217 (18) |
Co—O8 | 2.0645 (18) | N2—C6 | 1.476 (4) |
Co—O8i | 2.0645 (18) | C1—C2 | 1.511 (3) |
Co—O1 | 2.0666 (17) | C2—C7 | 1.380 (3) |
Co—O1i | 2.0666 (16) | C2—C3 | 1.385 (3) |
Co—O7 | 2.1094 (16) | C3—C4 | 1.373 (3) |
Co—O7i | 2.1094 (16) | C3—H3 | 0.9300 |
O1—C1 | 1.250 (3) | C4—C5 | 1.371 (4) |
O2—C1 | 1.247 (3) | C5—C6 | 1.378 (4) |
O3—N1 | 1.179 (4) | C5—H5 | 0.9300 |
O4—N1 | 1.190 (3) | C6—C7 | 1.379 (4) |
O5—N2 | 1.220 (4) | C7—H7 | 0.9300 |
O6—N2 | 1.209 (4) | C8—H8A | 0.9600 |
O7—C8 | 1.418 (3) | C8—H8B | 0.9600 |
O7—H7O | 0.85 (3) | C8—H8C | 0.9600 |
O8—C9 | 1.408 (3) | C9—H9A | 0.9600 |
O8—H8O | 0.85 (3) | C9—H9B | 0.9600 |
N1—C4 | 1.482 (3) | C9—H9C | 0.9600 |
O8—Co—O1 | 91.36 (8) | C7—C2—C3 | 119.3 (2) |
O8i—Co—O1 | 88.64 (8) | C7—C2—C1 | 120.5 (2) |
O8—Co—O1i | 88.64 (8) | C3—C2—C1 | 120.2 (2) |
O8i—Co—O1i | 91.36 (8) | C4—C3—C2 | 119.1 (2) |
O8—Co—O7 | 88.14 (7) | C4—C3—H3 | 120.5 |
O8i—Co—O7 | 91.86 (7) | C2—C3—H3 | 120.5 |
O1—Co—O7 | 89.22 (7) | C5—C4—C3 | 123.3 (2) |
O1i—Co—O7 | 90.78 (7) | C5—C4—N1 | 119.3 (2) |
O8—Co—O7i | 91.86 (7) | C3—C4—N1 | 117.4 (2) |
O8i—Co—O7i | 88.14 (7) | C4—C5—C6 | 116.3 (2) |
O1—Co—O7i | 90.78 (7) | C4—C5—H5 | 121.9 |
O1i—Co—O7i | 89.22 (7) | C6—C5—H5 | 121.9 |
O1—Co—O1i | 180.0 | C5—C6—C7 | 122.6 (2) |
O7—Co—O7i | 180.0 | C5—C6—N2 | 119.1 (3) |
O8—Co—O8i | 180.0 | C7—C6—N2 | 118.3 (3) |
C1—O1—Co | 130.70 (16) | C6—C7—C2 | 119.4 (2) |
C8—O7—Co | 128.82 (16) | C6—C7—H7 | 120.3 |
C8—O7—H7O | 113 (2) | C2—C7—H7 | 120.3 |
Co—O7—H7O | 105 (2) | O7—C8—H8A | 109.5 |
C9—O8—Co | 131.57 (18) | O7—C8—H8B | 109.5 |
C9—O8—H8O | 110 (2) | H8A—C8—H8B | 109.5 |
Co—O8—H8O | 118 (2) | O7—C8—H8C | 109.5 |
O3—N1—O4 | 122.3 (3) | H8A—C8—H8C | 109.5 |
O3—N1—C4 | 118.6 (3) | H8B—C8—H8C | 109.5 |
O4—N1—C4 | 119.1 (3) | O8—C9—H9A | 109.5 |
O6—N2—O5 | 123.7 (3) | O8—C9—H9B | 109.5 |
O6—N2—C6 | 118.5 (3) | H9A—C9—H9B | 109.5 |
O5—N2—C6 | 117.8 (3) | O8—C9—H9C | 109.5 |
O2—C1—O1 | 126.1 (2) | H9A—C9—H9C | 109.5 |
O2—C1—C2 | 118.0 (2) | H9B—C9—H9C | 109.5 |
O1—C1—C2 | 115.9 (2) | ||
O8—Co—O1—C1 | 87.5 (2) | C1—C2—C3—C4 | −179.8 (2) |
O8i—Co—O1—C1 | −92.5 (2) | C2—C3—C4—C5 | 0.0 (4) |
O7—Co—O1—C1 | 175.6 (2) | C2—C3—C4—N1 | 179.5 (2) |
O7i—Co—O1—C1 | −4.4 (2) | O3—N1—C4—C5 | 173.0 (3) |
O8—Co—O7—C8 | 125.9 (2) | O4—N1—C4—C5 | −9.2 (5) |
O8i—Co—O7—C8 | −54.1 (2) | O3—N1—C4—C3 | −6.5 (5) |
O1—Co—O7—C8 | 34.5 (2) | O4—N1—C4—C3 | 171.2 (3) |
O1i—Co—O7—C8 | −145.5 (2) | C3—C4—C5—C6 | 0.2 (4) |
O1—Co—O8—C9 | −58.0 (3) | N1—C4—C5—C6 | −179.3 (3) |
O1i—Co—O8—C9 | 122.0 (3) | C4—C5—C6—C7 | −0.5 (4) |
O7—Co—O8—C9 | −147.1 (3) | C4—C5—C6—N2 | 178.2 (3) |
O7i—Co—O8—C9 | 32.9 (3) | O6—N2—C6—C5 | 177.2 (3) |
Co—O1—C1—O2 | −6.2 (4) | O5—N2—C6—C5 | −3.4 (5) |
Co—O1—C1—C2 | 175.42 (15) | O6—N2—C6—C7 | −4.0 (5) |
O2—C1—C2—C7 | −178.2 (2) | O5—N2—C6—C7 | 175.4 (3) |
O1—C1—C2—C7 | 0.3 (4) | C5—C6—C7—C2 | 0.6 (4) |
O2—C1—C2—C3 | 1.6 (4) | N2—C6—C7—C2 | −178.1 (3) |
O1—C1—C2—C3 | −179.9 (2) | C3—C2—C7—C6 | −0.3 (4) |
C7—C2—C3—C4 | 0.0 (4) | C1—C2—C7—C6 | 179.5 (2) |
Symmetry code: (i) −x+1, −y+1, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O7—H7o···O2i | 0.85 (3) | 1.84 (2) | 2.645 (2) | 158 (3) |
O8—H8o···O2ii | 0.85 (3) | 1.82 (1) | 2.662 (2) | 179 (3) |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x−1, y, z. |
Experimental details
Crystal data | |
Chemical formula | [Co(C7H3N2O6)2(CH4O)4] |
Mr | 609.33 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 293 |
a, b, c (Å) | 6.4068 (8), 8.7660 (11), 12.1603 (16) |
α, β, γ (°) | 90.411 (2), 100.407 (2), 102.214 (2) |
V (Å3) | 655.77 (14) |
Z | 1 |
Radiation type | Mo Kα |
µ (mm−1) | 0.74 |
Crystal size (mm) | 0.35 × 0.30 × 0.05 |
Data collection | |
Diffractometer | Bruker SMART APEX diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.669, 0.746 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6372, 2999, 2388 |
Rint | 0.028 |
(sin θ/λ)max (Å−1) | 0.650 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.043, 0.110, 1.03 |
No. of reflections | 2999 |
No. of parameters | 188 |
No. of restraints | 2 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.38, −0.30 |
Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006), publCIF (Westrip, 2010).
D—H···A | D—H | H···A | D···A | D—H···A |
O7—H7o···O2i | 0.85 (3) | 1.840 (15) | 2.645 (2) | 158 (3) |
O8—H8o···O2ii | 0.85 (3) | 1.817 (10) | 2.662 (2) | 179 (3) |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x−1, y, z. |
Footnotes
‡Additional correspondence author, e-mail: abhijitchem1947@yahoo.co.in.
Acknowledgements
The authors are grateful to the SAP (UGC), New Delhi, India, for financial support.
References
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The Co(II) atom in (I), Fig. 1, is located on a crystallographic centre of inversion and exists within an octahedral O6 donor set defined by two carboxylate-O1 atoms and four methanol-O atoms. The Co–O1 bond distance [Co–O1 = 2.0666 (17) Å] is comparable to those, i.e. 2.0525 (20) and 2.0587 (19) Å, found in the related tetra-aqua-bis(3,5-dinitrobenzoato-O)cobalt(II) tetrahydrate structure (Tahir et al., 1996; Yang et al., 2000; Jin et al., 2008). A small disparity in the Co—Omethanol bond distances in (I) [Co–O7 = 2.1094 (16) and Co–O8 = 2.0645 (18) Å] is noted. The methanol-O7–H hydrogen forms an intramolecular O–H···O hydrogen bond with the carbonyl-O2 atom to close an almost planar {Co–O–C–O···H–O} S(6) ring, Table 1. The methanol-O8–H also forms a hydrogen bond to the carbonyl-O2 atom on a centrosymmetrically related complex, Table 1. This results in the formation of 12-membered {Co–O–H···O–C–O}2 synthons and linear supramolecular chains along the a axis, Fig. 2. It is noted that the packing of molecules brings into close proximity two nitro-O atoms, i.e. O4···O4ii = 2.756 (3) Å for 3-x, -y, 2-z. While the nature of this interaction is not obvious, there are approximately 50 precedents for such Onitro···Onitro contacts < 2.70 Å in the crystallographic literature (Allen, 2002).