metal-organic compounds
Tetraaquabis[4-(pyrazin-2-ylsulfanylmethyl-κN4)benzoato]cobalt(II)
aCollege of Chemistry and Chemical Engineering, Pingdingshan University, Pingdingshan 467000, People's Republic of China
*Correspondence e-mail: lifuanpds@163.com
In the title compound, [Co(C12H9N2O2S)2(H2O)4], the CoII ion, lying on an inversion center, has an octahedral coordination involving two N atoms of two 4-(pyrazin-2-ylsulfanylmethyl)benzoate ligands and four water molecules. In the crystal, O—H⋯O hydrogen bonds between the coordinated water molecules and uncoordinated carboxylate O atoms, and weak π–π interactions [centroid–centroid distance = 4.105 (2) Å] between the benzene and pyrazine rings lead to a three-dimensional supramolecular network.
Related literature
For general background to the network topologies and applications of coordination polymers, see: Han et al. (2003); Zhao, Hong et al. (2002a,b); Zhao, Zou et al. (2004). For the synthesis and structure of a similar ligand, 4-(2-pyrimidinylthiomethyl)benzoic acid, see: Han et al. (2006).
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: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).
Supporting information
10.1107/S1600536810037906/hy2354sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536810037906/hy2354Isup2.hkl
The synthesis method of Hpztmb is similar to that of Hpmtmb (Han et al., 2006) except that 2-mercaptopyrazine was used instead of 2-mercaptopyrimidine. A mixture of Co(NO3)2.6H2O (29 mg, 0.1 mmol) and Hpztmb (50 mg, 0.2 mmol) in 10 ml of H2O was sealed in a stainless-steel reactor with a Teflon liner and heated at 383 K for 72 h. A quantity of red single crystals were obtained after the solution was cooled to room temperature at a rate of 10 K h-1.
H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93 (aromatic) and 0.97 (CH2) Å and Uiso(H) = 1.2Ueq(C). Water H atoms were found in difference Fourier maps and initially included with a tight O—H restraint [0.85 (1) Å]. In the final
the positions of the water H atoms were fixed, with Uiso(H) = 1.5Ueq(O).Data collection: APEX2 (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).[Co(C12H9N2O2S)2(H2O)4] | F(000) = 642 |
Mr = 621.54 | Dx = 1.591 Mg m−3 Dm = 1.591 Mg m−3 Dm measured by not measured |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 1622 reflections |
a = 14.6561 (11) Å | θ = 3.1–25.8° |
b = 11.0666 (8) Å | µ = 0.88 mm−1 |
c = 7.9973 (6) Å | T = 296 K |
β = 90.640 (1)° | Block, red |
V = 1297.03 (17) Å3 | 0.20 × 0.18 × 0.15 mm |
Z = 2 |
Bruker APEXII CCD diffractometer | 3097 independent reflections |
Radiation source: fine-focus sealed tube | 2131 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.045 |
ϕ and ω scans | θmax = 27.9°, θmin = 1.4° |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | h = −19→18 |
Tmin = 0.844, Tmax = 0.879 | k = −14→10 |
7415 measured reflections | l = −5→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)] = 0.042 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.126 | H-atom parameters constrained |
S = 0.98 | w = 1/[σ2(Fo2) + (0.0691P)2] where P = (Fo2 + 2Fc2)/3 |
3097 reflections | (Δ/σ)max < 0.001 |
178 parameters | Δρmax = 0.41 e Å−3 |
0 restraints | Δρmin = −0.37 e Å−3 |
[Co(C12H9N2O2S)2(H2O)4] | V = 1297.03 (17) Å3 |
Mr = 621.54 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 14.6561 (11) Å | µ = 0.88 mm−1 |
b = 11.0666 (8) Å | T = 296 K |
c = 7.9973 (6) Å | 0.20 × 0.18 × 0.15 mm |
β = 90.640 (1)° |
Bruker APEXII CCD diffractometer | 3097 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | 2131 reflections with I > 2σ(I) |
Tmin = 0.844, Tmax = 0.879 | Rint = 0.045 |
7415 measured reflections |
R[F2 > 2σ(F2)] = 0.042 | 0 restraints |
wR(F2) = 0.126 | H-atom parameters constrained |
S = 0.98 | Δρmax = 0.41 e Å−3 |
3097 reflections | Δρmin = −0.37 e Å−3 |
178 parameters |
x | y | z | Uiso*/Ueq | ||
Co1 | 1.0000 | 0.5000 | 1.0000 | 0.02141 (16) | |
O1 | 0.17691 (15) | 0.4653 (2) | 0.4237 (3) | 0.0410 (6) | |
O2 | 0.11201 (13) | 0.3613 (2) | 0.6281 (2) | 0.0306 (5) | |
O1W | 1.01980 (14) | 0.4766 (2) | 1.2565 (2) | 0.0342 (5) | |
H1WA | 0.9824 | 0.5172 | 1.3073 | 0.051* | |
H1WB | 1.0659 | 0.4712 | 1.3069 | 0.051* | |
O2W | 0.94265 (16) | 0.66681 (19) | 1.0537 (3) | 0.0388 (6) | |
H2WB | 0.9184 | 0.6641 | 1.1455 | 0.058* | |
H2WA | 0.9283 | 0.7237 | 0.9993 | 0.058* | |
N1 | 0.86650 (16) | 0.4200 (2) | 1.0353 (3) | 0.0263 (5) | |
N2 | 0.70190 (17) | 0.2923 (2) | 1.0414 (3) | 0.0343 (6) | |
C1 | 0.79056 (19) | 0.4640 (3) | 0.9652 (4) | 0.0254 (6) | |
H1 | 0.7924 | 0.5392 | 0.9134 | 0.030* | |
C2 | 0.70864 (19) | 0.4004 (3) | 0.9674 (3) | 0.0262 (6) | |
C3 | 0.7784 (2) | 0.2507 (3) | 1.1130 (4) | 0.0373 (8) | |
H3 | 0.7764 | 0.1763 | 1.1669 | 0.045* | |
C4 | 0.8597 (2) | 0.3120 (3) | 1.1112 (4) | 0.0347 (8) | |
H4 | 0.9108 | 0.2784 | 1.1631 | 0.042* | |
C5 | 0.5369 (2) | 0.3367 (3) | 0.8688 (5) | 0.0406 (9) | |
H5A | 0.5643 | 0.2679 | 0.8136 | 0.049* | |
H5B | 0.5274 | 0.3149 | 0.9848 | 0.049* | |
C6 | 0.44575 (19) | 0.3625 (3) | 0.7878 (4) | 0.0278 (7) | |
C7 | 0.4284 (2) | 0.4607 (3) | 0.6838 (4) | 0.0313 (7) | |
H7 | 0.4745 | 0.5161 | 0.6629 | 0.038* | |
C8 | 0.3426 (2) | 0.4770 (3) | 0.6107 (4) | 0.0284 (7) | |
H8 | 0.3324 | 0.5422 | 0.5396 | 0.034* | |
C9 | 0.27219 (18) | 0.3965 (3) | 0.6431 (3) | 0.0237 (6) | |
C10 | 0.2892 (2) | 0.2995 (3) | 0.7504 (4) | 0.0300 (7) | |
H10 | 0.2424 | 0.2458 | 0.7752 | 0.036* | |
C11 | 0.3750 (2) | 0.2825 (3) | 0.8202 (4) | 0.0315 (7) | |
H11 | 0.3855 | 0.2166 | 0.8898 | 0.038* | |
C12 | 0.18071 (18) | 0.4100 (3) | 0.5590 (3) | 0.0254 (6) | |
S1 | 0.61446 (5) | 0.46202 (8) | 0.86052 (11) | 0.0350 (2) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Co1 | 0.0161 (3) | 0.0262 (3) | 0.0219 (3) | 0.0013 (2) | −0.00308 (19) | 0.0018 (2) |
O1 | 0.0273 (12) | 0.0612 (17) | 0.0342 (12) | −0.0043 (11) | −0.0104 (10) | 0.0150 (11) |
O2 | 0.0206 (11) | 0.0422 (13) | 0.0291 (11) | −0.0056 (9) | 0.0006 (9) | −0.0023 (9) |
O1W | 0.0243 (11) | 0.0539 (16) | 0.0241 (10) | 0.0068 (10) | −0.0071 (9) | −0.0008 (9) |
O2W | 0.0532 (15) | 0.0305 (13) | 0.0330 (12) | 0.0129 (11) | 0.0120 (11) | 0.0073 (10) |
N1 | 0.0198 (12) | 0.0315 (15) | 0.0274 (12) | −0.0017 (10) | −0.0027 (10) | 0.0012 (11) |
N2 | 0.0242 (14) | 0.0395 (17) | 0.0393 (16) | −0.0048 (11) | −0.0039 (12) | 0.0096 (12) |
C1 | 0.0221 (15) | 0.0297 (16) | 0.0243 (14) | 0.0000 (11) | −0.0029 (11) | 0.0007 (12) |
C2 | 0.0205 (14) | 0.0357 (18) | 0.0222 (14) | 0.0002 (12) | −0.0040 (11) | −0.0019 (12) |
C3 | 0.0318 (17) | 0.039 (2) | 0.0412 (19) | −0.0025 (14) | −0.0051 (14) | 0.0144 (15) |
C4 | 0.0247 (16) | 0.040 (2) | 0.0389 (18) | 0.0008 (14) | −0.0057 (13) | 0.0107 (15) |
C5 | 0.0238 (17) | 0.044 (2) | 0.054 (2) | −0.0065 (14) | −0.0137 (15) | 0.0147 (16) |
C6 | 0.0206 (14) | 0.0349 (18) | 0.0277 (15) | −0.0008 (12) | −0.0034 (12) | 0.0019 (13) |
C7 | 0.0205 (15) | 0.0365 (18) | 0.0369 (17) | −0.0060 (13) | −0.0056 (12) | 0.0076 (14) |
C8 | 0.0262 (15) | 0.0307 (19) | 0.0281 (15) | −0.0023 (12) | −0.0041 (12) | 0.0053 (12) |
C9 | 0.0190 (14) | 0.0294 (17) | 0.0225 (14) | 0.0012 (11) | −0.0025 (11) | −0.0040 (12) |
C10 | 0.0203 (15) | 0.0338 (18) | 0.0358 (17) | −0.0057 (12) | −0.0020 (12) | 0.0043 (13) |
C11 | 0.0247 (15) | 0.0320 (18) | 0.0376 (17) | −0.0008 (13) | −0.0058 (13) | 0.0102 (14) |
C12 | 0.0189 (14) | 0.0314 (17) | 0.0257 (15) | −0.0010 (12) | −0.0031 (11) | −0.0074 (12) |
S1 | 0.0230 (4) | 0.0354 (5) | 0.0464 (5) | −0.0027 (3) | −0.0123 (3) | 0.0062 (4) |
Co1—O1W | 2.085 (2) | C3—H3 | 0.9300 |
Co1—O2W | 2.075 (2) | C4—H4 | 0.9300 |
Co1—N1 | 2.169 (2) | C5—C6 | 1.505 (4) |
O1—C12 | 1.244 (4) | C5—S1 | 1.795 (3) |
O2—C12 | 1.274 (3) | C5—H5A | 0.9700 |
O1W—H1WA | 0.8200 | C5—H5B | 0.9700 |
O1W—H1WB | 0.7849 | C6—C7 | 1.390 (4) |
O2W—H2WB | 0.8200 | C6—C11 | 1.390 (4) |
O2W—H2WA | 0.7924 | C7—C8 | 1.392 (4) |
N1—C1 | 1.333 (4) | C7—H7 | 0.9300 |
N1—C4 | 1.345 (4) | C8—C9 | 1.390 (4) |
N2—C3 | 1.334 (4) | C8—H8 | 0.9300 |
N2—C2 | 1.339 (4) | C9—C10 | 1.395 (4) |
C1—C2 | 1.392 (4) | C9—C12 | 1.501 (4) |
C1—H1 | 0.9300 | C10—C11 | 1.383 (4) |
C2—S1 | 1.753 (3) | C10—H10 | 0.9300 |
C3—C4 | 1.371 (4) | C11—H11 | 0.9300 |
O2W—Co1—O2Wi | 180.000 (1) | C4—C3—H3 | 118.3 |
O2W—Co1—O1W | 87.66 (9) | N1—C4—C3 | 120.9 (3) |
O2Wi—Co1—O1W | 92.34 (9) | N1—C4—H4 | 119.6 |
O2W—Co1—O1Wi | 92.34 (9) | C3—C4—H4 | 119.6 |
O2Wi—Co1—O1Wi | 87.66 (9) | C6—C5—S1 | 113.4 (2) |
O1W—Co1—O1Wi | 180.000 (1) | C6—C5—H5A | 108.9 |
O2W—Co1—N1i | 91.83 (9) | S1—C5—H5A | 108.9 |
O2Wi—Co1—N1i | 88.17 (9) | C6—C5—H5B | 108.9 |
O1W—Co1—N1i | 93.62 (9) | S1—C5—H5B | 108.9 |
O1Wi—Co1—N1i | 86.38 (9) | H5A—C5—H5B | 107.7 |
O2W—Co1—N1 | 88.17 (9) | C7—C6—C11 | 118.5 (3) |
O2Wi—Co1—N1 | 91.83 (9) | C7—C6—C5 | 124.2 (3) |
O1W—Co1—N1 | 86.38 (9) | C11—C6—C5 | 117.3 (3) |
O1Wi—Co1—N1 | 93.62 (9) | C6—C7—C8 | 120.8 (3) |
N1i—Co1—N1 | 180.00 (13) | C6—C7—H7 | 119.6 |
Co1—O1W—H1WA | 109.5 | C8—C7—H7 | 119.6 |
Co1—O1W—H1WB | 128.6 | C9—C8—C7 | 120.5 (3) |
H1WA—O1W—H1WB | 111.3 | C9—C8—H8 | 119.8 |
Co1—O2W—H2WB | 109.5 | C7—C8—H8 | 119.8 |
Co1—O2W—H2WA | 134.4 | C8—C9—C10 | 118.7 (3) |
H2WB—O2W—H2WA | 113.9 | C8—C9—C12 | 120.9 (3) |
C1—N1—C4 | 116.6 (3) | C10—C9—C12 | 120.3 (3) |
C1—N1—Co1 | 123.1 (2) | C11—C10—C9 | 120.5 (3) |
C4—N1—Co1 | 119.6 (2) | C11—C10—H10 | 119.7 |
C3—N2—C2 | 115.6 (3) | C9—C10—H10 | 119.7 |
N1—C1—C2 | 121.8 (3) | C10—C11—C6 | 121.0 (3) |
N1—C1—H1 | 119.1 | C10—C11—H11 | 119.5 |
C2—C1—H1 | 119.1 | C6—C11—H11 | 119.5 |
N2—C2—C1 | 121.7 (3) | O1—C12—O2 | 123.9 (3) |
N2—C2—S1 | 120.1 (2) | O1—C12—C9 | 118.0 (3) |
C1—C2—S1 | 118.2 (2) | O2—C12—C9 | 118.1 (3) |
N2—C3—C4 | 123.4 (3) | C2—S1—C5 | 100.22 (15) |
N2—C3—H3 | 118.3 | ||
O2W—Co1—N1—C1 | 48.1 (2) | S1—C5—C6—C11 | −165.9 (2) |
O2Wi—Co1—N1—C1 | −131.9 (2) | C11—C6—C7—C8 | −1.5 (5) |
O1W—Co1—N1—C1 | 135.9 (2) | C5—C6—C7—C8 | 178.6 (3) |
O1Wi—Co1—N1—C1 | −44.1 (2) | C6—C7—C8—C9 | 1.3 (5) |
O2W—Co1—N1—C4 | −141.6 (2) | C7—C8—C9—C10 | 0.1 (4) |
O2Wi—Co1—N1—C4 | 38.4 (2) | C7—C8—C9—C12 | −177.2 (3) |
O1W—Co1—N1—C4 | −53.8 (2) | C8—C9—C10—C11 | −1.4 (4) |
O1Wi—Co1—N1—C4 | 126.2 (2) | C12—C9—C10—C11 | 176.0 (3) |
C4—N1—C1—C2 | −1.2 (4) | C9—C10—C11—C6 | 1.2 (5) |
Co1—N1—C1—C2 | 169.4 (2) | C7—C6—C11—C10 | 0.3 (5) |
C3—N2—C2—C1 | 0.4 (4) | C5—C6—C11—C10 | −179.8 (3) |
C3—N2—C2—S1 | 177.1 (2) | C8—C9—C12—O1 | 23.7 (4) |
N1—C1—C2—N2 | 0.6 (5) | C10—C9—C12—O1 | −153.6 (3) |
N1—C1—C2—S1 | −176.1 (2) | C8—C9—C12—O2 | −158.2 (3) |
C2—N2—C3—C4 | −0.7 (5) | C10—C9—C12—O2 | 24.5 (4) |
C1—N1—C4—C3 | 0.9 (5) | N2—C2—S1—C5 | −6.9 (3) |
Co1—N1—C4—C3 | −170.1 (3) | C1—C2—S1—C5 | 169.9 (2) |
N2—C3—C4—N1 | 0.1 (5) | C6—C5—S1—C2 | 178.9 (2) |
S1—C5—C6—C7 | 14.0 (4) |
Symmetry code: (i) −x+2, −y+1, −z+2. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1W—H1WA···O2ii | 0.82 | 2.00 | 2.801 (3) | 165 |
O1W—H1WB···O1iii | 0.78 | 1.87 | 2.653 (3) | 177 |
O2W—H2WA···O2iv | 0.79 | 1.92 | 2.713 (3) | 177 |
O2W—H2WB···O2ii | 0.82 | 1.89 | 2.695 (3) | 167 |
Symmetry codes: (ii) −x+1, −y+1, −z+2; (iii) x+1, y, z+1; (iv) −x+1, y+1/2, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | [Co(C12H9N2O2S)2(H2O)4] |
Mr | 621.54 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 296 |
a, b, c (Å) | 14.6561 (11), 11.0666 (8), 7.9973 (6) |
β (°) | 90.640 (1) |
V (Å3) | 1297.03 (17) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.88 |
Crystal size (mm) | 0.20 × 0.18 × 0.15 |
Data collection | |
Diffractometer | Bruker APEXII CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2001) |
Tmin, Tmax | 0.844, 0.879 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7415, 3097, 2131 |
Rint | 0.045 |
(sin θ/λ)max (Å−1) | 0.659 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.042, 0.126, 0.98 |
No. of reflections | 3097 |
No. of parameters | 178 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.41, −0.37 |
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
O1W—H1WA···O2i | 0.82 | 2.00 | 2.801 (3) | 165 |
O1W—H1WB···O1ii | 0.78 | 1.87 | 2.653 (3) | 177 |
O2W—H2WA···O2iii | 0.79 | 1.92 | 2.713 (3) | 177 |
O2W—H2WB···O2i | 0.82 | 1.89 | 2.695 (3) | 167 |
Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) x+1, y, z+1; (iii) −x+1, y+1/2, −z+3/2. |
Acknowledgements
This work was supported financially by the College of Chemistry and Chemical Engineering, Pingdingshan University, China.
References
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Crystal engineering based on metal–organic frameworks (MOFs) using asymmetric bridging ligands as building blocks has attracted much attention owing to their potential applications as second-order nonlinear optical (NLO) materials (Han et al., 2003; Zhao, Hong et al., 2002a,b). The combination of hydrogen bonding and π–π interactions has proved to be particularly useful for the assembly of MOFs (Zhao, Zou et al., 2004). Recently we have begun working on the architectures of polymeric structures containing a novel long and flexible monoanionic ligand with hybrid pyrazine and benzoate groups, namely 4-(2-pyrazinylthiomethyl)benzoic acid (Hpztmb). We report herein the synthesis and crystal structure of the title complex [Co(pztmb)2(H2O)4].
The title compound comprises of one CoII ion, two pztmb ligands and four coordinated water molecules (Fig. 1). The CoII ion lies on an inversion center in an octahedral coordination environment, with four O atoms from four coordinated water molecules in the equatorial positions and two N atoms from two different pztmb ligands in the axial sites (Table 1). The uncoordinated carboxylate O atoms and the coordinated water molecules form abundant strong hydrogen bonds (Table 2). In addition, two neighboring pztmb ligands are parallel and inversely arranged so that there is a weak π–π interaction [centroid–centroid distance = 4.105 (2) Å] between the benzene ring of one pztmb ligand and the pyrazine ring of the other one. Consequently, the hydrogen bonds and weak π–π interactions lead to a three-dimensional supramolecular network (Fig. 2).