metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

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

(Received 11 September 2010; accepted 22 September 2010; online 30 September 2010)

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 ππ 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[Han, L., Hong, M.-C., Wang, R.-H., Luo, J.-H., Lin, Z.-Z. & Yuan, D.-Q. (2003). Chem. Commun. pp. 2580-2581.]); Zhao, Hong et al. (2002a[Zhao, Y.-J., Hong, M.-C., Sun, D.-F. & Cao, R. (2002a). Inorg. Chim. Acta, 5, 565-568.],b[Zhao, Y.-J., Hong, M.-C., Sun, D.-F. & Cao, R. (2002b). J. Chem. Soc. Dalton Trans. pp. 1354-1357.]); Zhao, Zou et al. (2004[Zhao, W.-N., Zou, J.-W. & Yu, Q.-S. (2004). Acta Cryst. C60, m443-m444.]). For the synthesis and structure of a similar ligand, 4-(2-pyrimidinyl­thio­meth­yl)benzoic acid, see: Han et al. (2006[Han, L., Yuan, D.-Q., Wu, B.-L., Liu, C.-P. & Hong, M.-C. (2006). Inorg. Chim. Acta, 359, 2232-2240.]).

[Scheme 1]

Experimental

Crystal data
  • [Co(C12H9N2O2S)2(H2O)4]

  • Mr = 621.54

  • Monoclinic, P 21 /c

  • a = 14.6561 (11) Å

  • b = 11.0666 (8) Å

  • c = 7.9973 (6) Å

  • β = 90.640 (1)°

  • V = 1297.03 (17) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.88 mm−1

  • T = 296 K

  • 0.20 × 0.18 × 0.15 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2001[Bruker (2001). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.844, Tmax = 0.879

  • 7415 measured reflections

  • 3097 independent reflections

  • 2131 reflections with I > 2σ(I)

  • Rint = 0.045

Refinement
  • R[F2 > 2σ(F2)] = 0.042

  • wR(F2) = 0.126

  • S = 0.98

  • 3097 reflections

  • 178 parameters

  • H-atom parameters constrained

  • Δρmax = 0.41 e Å−3

  • Δρmin = −0.37 e Å−3

Table 1
Selected bond lengths (Å)

Co1—O1W 2.085 (2)
Co1—O2W 2.075 (2)
Co1—N1 2.169 (2)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA 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+{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: DIAMOND (Brandenburg, 1999[Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

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 ππ 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 ππ 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 ππ interactions lead to a three-dimensional supramolecular network (Fig. 2).

Related literature top

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 top

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.

Refinement top

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 refinement, the positions of the water H atoms were fixed, with Uiso(H) = 1.5Ueq(O).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: 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).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level. [Symmetry code: (i) 2-x, 1-y, 2-z.]
[Figure 2] Fig. 2. Three-dimensional supramolecular structure of the title compound. H atoms have been omitted for clarity. Dashed lines indicate hydrogen bonds and weak ππ interactions.
Tetraaquabis[4-(pyrazin-2-ylsulfanylmethyl-κN4)benzoato]cobalt(II) top
Crystal data top
[Co(C12H9N2O2S)2(H2O)4]F(000) = 642
Mr = 621.54Dx = 1.591 Mg m3
Dm = 1.591 Mg m3
Dm measured by not measured
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1622 reflections
a = 14.6561 (11) Åθ = 3.1–25.8°
b = 11.0666 (8) ŵ = 0.88 mm1
c = 7.9973 (6) ÅT = 296 K
β = 90.640 (1)°Block, red
V = 1297.03 (17) Å30.20 × 0.18 × 0.15 mm
Z = 2
Data collection top
Bruker APEXII CCD
diffractometer
3097 independent reflections
Radiation source: fine-focus sealed tube2131 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.045
ϕ and ω scansθmax = 27.9°, θmin = 1.4°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
h = 1918
Tmin = 0.844, Tmax = 0.879k = 1410
7415 measured reflectionsl = 510
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.042Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.126H-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 parametersΔρmax = 0.41 e Å3
0 restraintsΔρmin = 0.37 e Å3
Crystal data top
[Co(C12H9N2O2S)2(H2O)4]V = 1297.03 (17) Å3
Mr = 621.54Z = 2
Monoclinic, P21/cMo Kα radiation
a = 14.6561 (11) ŵ = 0.88 mm1
b = 11.0666 (8) ÅT = 296 K
c = 7.9973 (6) Å0.20 × 0.18 × 0.15 mm
β = 90.640 (1)°
Data collection top
Bruker APEXII CCD
diffractometer
3097 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
2131 reflections with I > 2σ(I)
Tmin = 0.844, Tmax = 0.879Rint = 0.045
7415 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0420 restraints
wR(F2) = 0.126H-atom parameters constrained
S = 0.98Δρmax = 0.41 e Å3
3097 reflectionsΔρmin = 0.37 e Å3
178 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Co11.00000.50001.00000.02141 (16)
O10.17691 (15)0.4653 (2)0.4237 (3)0.0410 (6)
O20.11201 (13)0.3613 (2)0.6281 (2)0.0306 (5)
O1W1.01980 (14)0.4766 (2)1.2565 (2)0.0342 (5)
H1WA0.98240.51721.30730.051*
H1WB1.06590.47121.30690.051*
O2W0.94265 (16)0.66681 (19)1.0537 (3)0.0388 (6)
H2WB0.91840.66411.14550.058*
H2WA0.92830.72370.99930.058*
N10.86650 (16)0.4200 (2)1.0353 (3)0.0263 (5)
N20.70190 (17)0.2923 (2)1.0414 (3)0.0343 (6)
C10.79056 (19)0.4640 (3)0.9652 (4)0.0254 (6)
H10.79240.53920.91340.030*
C20.70864 (19)0.4004 (3)0.9674 (3)0.0262 (6)
C30.7784 (2)0.2507 (3)1.1130 (4)0.0373 (8)
H30.77640.17631.16690.045*
C40.8597 (2)0.3120 (3)1.1112 (4)0.0347 (8)
H40.91080.27841.16310.042*
C50.5369 (2)0.3367 (3)0.8688 (5)0.0406 (9)
H5A0.56430.26790.81360.049*
H5B0.52740.31490.98480.049*
C60.44575 (19)0.3625 (3)0.7878 (4)0.0278 (7)
C70.4284 (2)0.4607 (3)0.6838 (4)0.0313 (7)
H70.47450.51610.66290.038*
C80.3426 (2)0.4770 (3)0.6107 (4)0.0284 (7)
H80.33240.54220.53960.034*
C90.27219 (18)0.3965 (3)0.6431 (3)0.0237 (6)
C100.2892 (2)0.2995 (3)0.7504 (4)0.0300 (7)
H100.24240.24580.77520.036*
C110.3750 (2)0.2825 (3)0.8202 (4)0.0315 (7)
H110.38550.21660.88980.038*
C120.18071 (18)0.4100 (3)0.5590 (3)0.0254 (6)
S10.61446 (5)0.46202 (8)0.86052 (11)0.0350 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.0161 (3)0.0262 (3)0.0219 (3)0.0013 (2)0.00308 (19)0.0018 (2)
O10.0273 (12)0.0612 (17)0.0342 (12)0.0043 (11)0.0104 (10)0.0150 (11)
O20.0206 (11)0.0422 (13)0.0291 (11)0.0056 (9)0.0006 (9)0.0023 (9)
O1W0.0243 (11)0.0539 (16)0.0241 (10)0.0068 (10)0.0071 (9)0.0008 (9)
O2W0.0532 (15)0.0305 (13)0.0330 (12)0.0129 (11)0.0120 (11)0.0073 (10)
N10.0198 (12)0.0315 (15)0.0274 (12)0.0017 (10)0.0027 (10)0.0012 (11)
N20.0242 (14)0.0395 (17)0.0393 (16)0.0048 (11)0.0039 (12)0.0096 (12)
C10.0221 (15)0.0297 (16)0.0243 (14)0.0000 (11)0.0029 (11)0.0007 (12)
C20.0205 (14)0.0357 (18)0.0222 (14)0.0002 (12)0.0040 (11)0.0019 (12)
C30.0318 (17)0.039 (2)0.0412 (19)0.0025 (14)0.0051 (14)0.0144 (15)
C40.0247 (16)0.040 (2)0.0389 (18)0.0008 (14)0.0057 (13)0.0107 (15)
C50.0238 (17)0.044 (2)0.054 (2)0.0065 (14)0.0137 (15)0.0147 (16)
C60.0206 (14)0.0349 (18)0.0277 (15)0.0008 (12)0.0034 (12)0.0019 (13)
C70.0205 (15)0.0365 (18)0.0369 (17)0.0060 (13)0.0056 (12)0.0076 (14)
C80.0262 (15)0.0307 (19)0.0281 (15)0.0023 (12)0.0041 (12)0.0053 (12)
C90.0190 (14)0.0294 (17)0.0225 (14)0.0012 (11)0.0025 (11)0.0040 (12)
C100.0203 (15)0.0338 (18)0.0358 (17)0.0057 (12)0.0020 (12)0.0043 (13)
C110.0247 (15)0.0320 (18)0.0376 (17)0.0008 (13)0.0058 (13)0.0102 (14)
C120.0189 (14)0.0314 (17)0.0257 (15)0.0010 (12)0.0031 (11)0.0074 (12)
S10.0230 (4)0.0354 (5)0.0464 (5)0.0027 (3)0.0123 (3)0.0062 (4)
Geometric parameters (Å, º) top
Co1—O1W2.085 (2)C3—H30.9300
Co1—O2W2.075 (2)C4—H40.9300
Co1—N12.169 (2)C5—C61.505 (4)
O1—C121.244 (4)C5—S11.795 (3)
O2—C121.274 (3)C5—H5A0.9700
O1W—H1WA0.8200C5—H5B0.9700
O1W—H1WB0.7849C6—C71.390 (4)
O2W—H2WB0.8200C6—C111.390 (4)
O2W—H2WA0.7924C7—C81.392 (4)
N1—C11.333 (4)C7—H70.9300
N1—C41.345 (4)C8—C91.390 (4)
N2—C31.334 (4)C8—H80.9300
N2—C21.339 (4)C9—C101.395 (4)
C1—C21.392 (4)C9—C121.501 (4)
C1—H10.9300C10—C111.383 (4)
C2—S11.753 (3)C10—H100.9300
C3—C41.371 (4)C11—H110.9300
O2W—Co1—O2Wi180.000 (1)C4—C3—H3118.3
O2W—Co1—O1W87.66 (9)N1—C4—C3120.9 (3)
O2Wi—Co1—O1W92.34 (9)N1—C4—H4119.6
O2W—Co1—O1Wi92.34 (9)C3—C4—H4119.6
O2Wi—Co1—O1Wi87.66 (9)C6—C5—S1113.4 (2)
O1W—Co1—O1Wi180.000 (1)C6—C5—H5A108.9
O2W—Co1—N1i91.83 (9)S1—C5—H5A108.9
O2Wi—Co1—N1i88.17 (9)C6—C5—H5B108.9
O1W—Co1—N1i93.62 (9)S1—C5—H5B108.9
O1Wi—Co1—N1i86.38 (9)H5A—C5—H5B107.7
O2W—Co1—N188.17 (9)C7—C6—C11118.5 (3)
O2Wi—Co1—N191.83 (9)C7—C6—C5124.2 (3)
O1W—Co1—N186.38 (9)C11—C6—C5117.3 (3)
O1Wi—Co1—N193.62 (9)C6—C7—C8120.8 (3)
N1i—Co1—N1180.00 (13)C6—C7—H7119.6
Co1—O1W—H1WA109.5C8—C7—H7119.6
Co1—O1W—H1WB128.6C9—C8—C7120.5 (3)
H1WA—O1W—H1WB111.3C9—C8—H8119.8
Co1—O2W—H2WB109.5C7—C8—H8119.8
Co1—O2W—H2WA134.4C8—C9—C10118.7 (3)
H2WB—O2W—H2WA113.9C8—C9—C12120.9 (3)
C1—N1—C4116.6 (3)C10—C9—C12120.3 (3)
C1—N1—Co1123.1 (2)C11—C10—C9120.5 (3)
C4—N1—Co1119.6 (2)C11—C10—H10119.7
C3—N2—C2115.6 (3)C9—C10—H10119.7
N1—C1—C2121.8 (3)C10—C11—C6121.0 (3)
N1—C1—H1119.1C10—C11—H11119.5
C2—C1—H1119.1C6—C11—H11119.5
N2—C2—C1121.7 (3)O1—C12—O2123.9 (3)
N2—C2—S1120.1 (2)O1—C12—C9118.0 (3)
C1—C2—S1118.2 (2)O2—C12—C9118.1 (3)
N2—C3—C4123.4 (3)C2—S1—C5100.22 (15)
N2—C3—H3118.3
O2W—Co1—N1—C148.1 (2)S1—C5—C6—C11165.9 (2)
O2Wi—Co1—N1—C1131.9 (2)C11—C6—C7—C81.5 (5)
O1W—Co1—N1—C1135.9 (2)C5—C6—C7—C8178.6 (3)
O1Wi—Co1—N1—C144.1 (2)C6—C7—C8—C91.3 (5)
O2W—Co1—N1—C4141.6 (2)C7—C8—C9—C100.1 (4)
O2Wi—Co1—N1—C438.4 (2)C7—C8—C9—C12177.2 (3)
O1W—Co1—N1—C453.8 (2)C8—C9—C10—C111.4 (4)
O1Wi—Co1—N1—C4126.2 (2)C12—C9—C10—C11176.0 (3)
C4—N1—C1—C21.2 (4)C9—C10—C11—C61.2 (5)
Co1—N1—C1—C2169.4 (2)C7—C6—C11—C100.3 (5)
C3—N2—C2—C10.4 (4)C5—C6—C11—C10179.8 (3)
C3—N2—C2—S1177.1 (2)C8—C9—C12—O123.7 (4)
N1—C1—C2—N20.6 (5)C10—C9—C12—O1153.6 (3)
N1—C1—C2—S1176.1 (2)C8—C9—C12—O2158.2 (3)
C2—N2—C3—C40.7 (5)C10—C9—C12—O224.5 (4)
C1—N1—C4—C30.9 (5)N2—C2—S1—C56.9 (3)
Co1—N1—C4—C3170.1 (3)C1—C2—S1—C5169.9 (2)
N2—C3—C4—N10.1 (5)C6—C5—S1—C2178.9 (2)
S1—C5—C6—C714.0 (4)
Symmetry code: (i) x+2, y+1, z+2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WA···O2ii0.822.002.801 (3)165
O1W—H1WB···O1iii0.781.872.653 (3)177
O2W—H2WA···O2iv0.791.922.713 (3)177
O2W—H2WB···O2ii0.821.892.695 (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]
Mr621.54
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)14.6561 (11), 11.0666 (8), 7.9973 (6)
β (°) 90.640 (1)
V3)1297.03 (17)
Z2
Radiation typeMo Kα
µ (mm1)0.88
Crystal size (mm)0.20 × 0.18 × 0.15
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2001)
Tmin, Tmax0.844, 0.879
No. of measured, independent and
observed [I > 2σ(I)] reflections
7415, 3097, 2131
Rint0.045
(sin θ/λ)max1)0.659
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.126, 0.98
No. of reflections3097
No. of parameters178
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.41, 0.37

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top
Co1—O1W2.085 (2)Co1—N12.169 (2)
Co1—O2W2.075 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WA···O2i0.822.002.801 (3)165
O1W—H1WB···O1ii0.781.872.653 (3)177
O2W—H2WA···O2iii0.791.922.713 (3)177
O2W—H2WB···O2i0.821.892.695 (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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