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Monoclinic polymorph of trans-tetra­aquabis­[(4-pyridylsulfanyl)­acetato-κN]cobalt(II)

aDepartment of Inorganic Chemistry, Slovak, Technical University, Radlinského 9, SK-812 37, Bratislava, Slovakia, and bDepartment of Chemistry, Faculty of Natural Science, University of St. Cyril and Methodius, SK-91701 Trnava, Slovakia
*Correspondence e-mail: jan.moncol@stuba.sk

(Received 12 June 2008; accepted 25 July 2008; online 31 July 2008)

The crystal structure of the title compound, [Co(C7H6NO2S)2(H2O)4], is a polymorph of the structure first reported by Du, Zhao & Wang [(2004). Dalton Trans, pp. 2065–2072]. The asymmetric unit of the title compound contains one half-mol­ecule; the CoII atom lies on an inversion centre in a distorted octa­hedral geometry coordinated by two N atoms of the pyridine rings of the 4-pyridylthio­acetate anions and four O atoms of water mol­ecules. In the crystal structure, inter­molecular O—H⋯O hydrogen bonds link the mol­ecules, forming a three-dimensional network.

Related literature

For related literature, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]); Chiang et al. (1993[Chiang, W., Ho, D. M., Van Engen, D. & Thompson, M. E. (1993). Inorg. Chem. 32, 2886-2893.]); Du et al. (2004[Du, M., Zhao, X.-J. & Wang, Y. (2004). Dalton Trans. pp. 2065-2072.]); Du & Li (2006[Du, M. & Li, C.-P. (2006). Inorg. Chim. Acta, 359, 1690-1696.]); Kondo et al. (2002[Kondo, M., Miyazawa, M., Irie, Y., Shinagawa, R., Horiba, T., Nakamura, A., Naito, T., Maeda, K., Utsuno, S. & Uchida, F. (2002). Chem. Commun. pp. 2156-2157.]); For related structures, see: Fang et al. (2004[Fang, R.-Q., Zhang, X.-M., Wu, H.-S. & Ng, S. W. (2004). Acta Cryst. E60, m401-m402.]); Zhang et al. (2004[Zhang, X.-M., Fang, R.-Q., Wu, H.-S. & Ng, S. W. (2004). Acta Cryst. E60, m135-m136.]).

[Scheme 1]

Experimental

Crystal data
  • [Co(C7H6NO2S)2(H2O)4]

  • Mr = 467.37

  • Monoclinic, P 21 /c

  • a = 12.173 (1) Å

  • b = 10.479 (1) Å

  • c = 7.523 (2) Å

  • β = 106.78 (3)°

  • V = 918.8 (3) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 1.21 mm−1

  • T = 293 (2) K

  • 0.45 × 0.40 × 0.30 mm

Data collection
  • Siemens P4 diffractometer

  • Absorption correction: ψ scan (XEMP; Siemens, 1994[Siemens (1994). XSCANS and XEMP. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]) Tmin = 0.608, Tmax = 0.684

  • 3491 measured reflections

  • 2651 independent reflections

  • 2283 reflections with I > 2σ(I)

  • Rint = 0.024

  • 3 standard reflections every 97 reflections intensity decay: 2.0%

Refinement
  • R[F2 > 2σ(F2)] = 0.032

  • wR(F2) = 0.102

  • S = 1.37

  • 2651 reflections

  • 125 parameters

  • H-atom parameters constrained

  • Δρmax = 0.41 e Å−3

  • Δρmin = −0.37 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1W—H1W⋯O1i 0.82 2.05 2.849 (2) 163
O1W—H2W⋯O1ii 0.82 1.95 2.757 (2) 167
O2W—H3W⋯O2ii 0.82 1.91 2.725 (2) 176
O2W—H4W⋯O2iii 0.82 1.95 2.743 (2) 163
Symmetry codes: (i) [-x+2, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) -x+2, -y+1, -z+1; (iii) x-1, y, z.

Data collection: XSCANS (Siemens, 1994[Siemens (1994). XSCANS and XEMP. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: XSCANS; data reduction: XSCANS; 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: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: enCIFer (Allen et al. 2004[Allen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335-338.]).

Supporting information


Comment top

Several transition metal coordination polymers that contain bridging 4-pyridylthioacetate ligands have been reported recently (Chiang et al., 1993; Du et al., 2004; Du & Li, 2006; Kondo et al., 2002). However, if the 4-pyridylthioacetate anions are coordinated only as terminal ligands there is a possibility that they may also be able to participate in a hydrogen-bonding network. As part of our efforts to investigate metal(II) complexes based on pyridyl-carboxylic acids, we report herein the crystal structure of the title compound, (I).

In the molecular structure of (I) (Fig. 1) the CoII atom lies on an inversion centre and adopts a distorted octahedral coordination geometry with the two N atoms of the pyridine rings of the 4-pyridylthioacetate anions and the four O atoms of the water molecules, where the two symmetry related 4-pyridylthioacetate ligands are in trans positions.

The bond lengths and angles may be compared with the corresponding values in the triclinic polymorph [Co(C7H6NO2S)2(H2O)4] [(II); Du et al., 2004]. In (II), the CoII atom displays similar distorted octahedral coordination geometry, but the angle between the plane through the pyridine rings and that through the four water O atoms of 87.9° is closer to a right angle than the angle of 77.8° in (I). Correspondingly, the distance between the two planes of pyridine rings in (II) is shorter (0.22 Å) than that (0.80 Å) in (I). On the other hand, complex (I) is isostructural with [Cu(C7H6NO2S)2(H2O)4] [(III); Fang et al., (2004)] and [Ni(C7H6NO2S)2(H2O)4] [(IV); Zhang et al., (2004)].

In the crystal structure, intermolecular O–H···O hydrogen bonds (Table 1) link the molecules to form a three-dimensional network. The molecules of (I) lying in layers parallel to the ac plane are linked by O1W–H2W···O1ii; O2W–H3W···O2ii and O2W–H4W···O2iii [Symmetry codes: (ii) -x + 2, -y + 1, -z + 1; (iii) x - 1, y, z] hydrogen bonds (Fig. 2). The hydrogen bonds between two coordinated water molecules O2W and two carboxylate groups through only one carboxylate O atom (O2) of the carboxylate group create R42(8) rings (Bernstein et al., 1995). On the other hand, both O atoms of the two carboxylate groups and two coordinated water molecules create R44(12) rings (Bernstein et al., 1995) in the triclinic polymorph (II). The hydrogen bonds O1W–H1W···O1i [Symmetry code: (i) -x + 2, y - 1/2, -z + 1/2] link the layers to form a 3-D hydrogen bonding network (Fig. 3).

Related literature top

For related literature, see: Bernstein et al. (1995); Chiang et al. (1993); Du et al. (2004); Du & Li (2006); Kondo et al. (2002); For related structures, see: Fang et al. (2004); Zhang et al. (2004).

Experimental top

Well shaped red crystals of (I) suitable for X-ray analysis were prepared in an H-tube. An aqueous solution of the sodium salt of 4-pyridylthioacetic acid, was placed in the first part of the H-tube, and an aqueous solution of Co(II) sulfate in the second part. Crystals formed after two weeks, whereafter they were separated and dried at room temperature (yield 70%). Anal. Calc. for C14H20CoN2O8S2: C, 35.98; H, 4.31; N, 5.99; S, 13.72; Co, 12.61. Found: C, 35.82; H, 4.41; N, 5.90; S, 13.59; Co, 12.75%. Selected IR data (cm-1): 1570 (versus,br) (νa(COO-) + ν(C=N)), 1376 (versus) (νs(COO-)), 430 (m) (γ(py), pyridine ring out-of-plane bending). Electronic data (cm-1): 21200, 20300, 9200br.

Refinement top

All H atoms of C–H (aromatic and methylene) were placed in calculated positions (0.93 and 0.97 Å, respectively); isotropic displaced parameters were fixed [Uiso(H) = 1.2 Uiso(C) of C atoms to which they were attached] using a riding model. The water H atoms were placed in calculated positions (O–H = 0.82 Å); isotropic displacement parameters were fixed [Uiso(H) = 1.5Uiso(O)) of O atoms to which they were attached].

Computing details top

Data collection: XSCANS (Siemens, 1994); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: enCIFer (Allen et al., 2004).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound, with atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. A layer of molecules of (I). Hydrogen bonds are shown as dashed lines [Symmetry codes: (ii) -x + 2, -y + 1, -z + 1; (iii) x - 1, y, z].
[Figure 3] Fig. 3. Hydrogen bonds between layers of molecules of (I) [Symmetry code: (i) -x + 2, y - 1/2, -z + 1/2].
trans-tetraaquabis](4-pyridylsulfanyl)acetato-κN]cobalt(II) top
Crystal data top
[Co(C7H6NO2S)2(H2O)4]F(000) = 482
Mr = 467.37Dx = 1.689 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 25 reflections
a = 12.173 (1) Åθ = 1.7–7.9°
b = 10.479 (1) ŵ = 1.21 mm1
c = 7.523 (2) ÅT = 293 K
β = 106.78 (3)°Block, pink
V = 918.8 (3) Å30.45 × 0.40 × 0.30 mm
Z = 2
Data collection top
Siemens P4
diffractometer
2283 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.024
Graphite monochromatorθmax = 30.0°, θmin = 1.8°
2θ/ω scansh = 1716
Absorption correction: ψ scan
(XEMP; Siemens, 1994)
k = 141
Tmin = 0.608, Tmax = 0.684l = 110
3491 measured reflections3 standard reflections every 97 reflections
2651 independent reflections intensity decay: 2.0%
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.032H-atom parameters constrained
wR(F2) = 0.102 w = 1/[σ2(Fo2) + (0.0291P)2 + 0.3487P]
where P = (Fo2 + 2Fc2)/3
S = 1.37(Δ/σ)max = 0.001
2651 reflectionsΔρmax = 0.41 e Å3
125 parametersΔρmin = 0.37 e Å3
0 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.073 (6)
Crystal data top
[Co(C7H6NO2S)2(H2O)4]V = 918.8 (3) Å3
Mr = 467.37Z = 2
Monoclinic, P21/cMo Kα radiation
a = 12.173 (1) ŵ = 1.21 mm1
b = 10.479 (1) ÅT = 293 K
c = 7.523 (2) Å0.45 × 0.40 × 0.30 mm
β = 106.78 (3)°
Data collection top
Siemens P4
diffractometer
2283 reflections with I > 2σ(I)
Absorption correction: ψ scan
(XEMP; Siemens, 1994)
Rint = 0.024
Tmin = 0.608, Tmax = 0.6843 standard reflections every 97 reflections
3491 measured reflections intensity decay: 2.0%
2651 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0320 restraints
wR(F2) = 0.102H-atom parameters constrained
S = 1.37Δρmax = 0.41 e Å3
2651 reflectionsΔρmin = 0.37 e Å3
125 parameters
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Co10.50000.50000.00000.01988 (13)
S11.03489 (4)0.69603 (5)0.41990 (8)0.03026 (16)
O11.27843 (14)0.69566 (16)0.5784 (2)0.0379 (4)
O21.32163 (14)0.52026 (19)0.4432 (3)0.0413 (4)
O1W0.56051 (12)0.31434 (14)0.0783 (2)0.0303 (3)
H1W0.59520.27900.01350.046*
H2W0.59960.31140.18710.046*
O2W0.48936 (14)0.5278 (2)0.2660 (2)0.0386 (4)
H3W0.54700.51690.35360.058*
H4W0.43000.52670.29670.058*
N10.67362 (13)0.57244 (16)0.0968 (2)0.0246 (3)
C11.25327 (16)0.6025 (2)0.4709 (3)0.0294 (4)
C21.12871 (16)0.5827 (2)0.3577 (3)0.0296 (4)
H2A1.10510.49690.37820.036*
H2B1.12230.59150.22670.036*
C30.76428 (16)0.50244 (19)0.0894 (3)0.0249 (4)
H30.75080.42740.02050.030*
C40.87692 (16)0.5353 (2)0.1785 (3)0.0257 (4)
H40.93690.48340.16860.031*
C50.89935 (15)0.64675 (19)0.2828 (3)0.0228 (4)
C60.80572 (17)0.7236 (2)0.2835 (3)0.0305 (4)
H60.81710.80140.34580.037*
C70.69607 (17)0.6831 (2)0.1909 (3)0.0314 (5)
H70.63460.73500.19380.038*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.01396 (18)0.0244 (2)0.02025 (19)0.00132 (12)0.00333 (12)0.00054 (13)
S10.0187 (2)0.0350 (3)0.0329 (3)0.00349 (18)0.00085 (18)0.0080 (2)
O10.0261 (7)0.0401 (9)0.0392 (9)0.0061 (7)0.0036 (6)0.0038 (7)
O20.0210 (7)0.0621 (12)0.0403 (9)0.0061 (7)0.0078 (6)0.0027 (8)
O1W0.0248 (7)0.0294 (7)0.0337 (8)0.0049 (6)0.0034 (6)0.0022 (6)
O2W0.0234 (7)0.0702 (12)0.0225 (7)0.0067 (7)0.0068 (6)0.0021 (7)
N10.0169 (7)0.0273 (8)0.0281 (8)0.0001 (6)0.0041 (6)0.0015 (6)
C10.0168 (8)0.0434 (12)0.0263 (9)0.0039 (8)0.0034 (7)0.0109 (9)
C20.0172 (8)0.0392 (11)0.0297 (10)0.0010 (7)0.0026 (7)0.0015 (8)
C30.0189 (8)0.0261 (9)0.0287 (9)0.0022 (7)0.0049 (7)0.0042 (8)
C40.0169 (8)0.0272 (9)0.0317 (10)0.0009 (7)0.0050 (7)0.0023 (8)
C50.0173 (8)0.0266 (9)0.0230 (8)0.0013 (6)0.0033 (6)0.0005 (7)
C60.0226 (9)0.0286 (10)0.0382 (11)0.0003 (7)0.0053 (8)0.0108 (8)
C70.0197 (9)0.0307 (10)0.0416 (12)0.0037 (7)0.0053 (8)0.0067 (9)
Geometric parameters (Å, º) top
Co1—O2Wi2.0632 (16)N1—C31.340 (2)
Co1—O2W2.0632 (16)N1—C71.345 (3)
Co1—O1Wi2.1034 (15)C1—C21.524 (3)
Co1—O1W2.1034 (15)C2—H2A0.9700
Co1—N1i2.1644 (16)C2—H2B0.9700
Co1—N12.1644 (16)C3—C41.385 (3)
S1—C51.7523 (19)C3—H30.9300
S1—C21.800 (2)C4—C51.389 (3)
O1—C11.248 (3)C4—H40.9300
O2—C11.257 (3)C5—C61.397 (3)
O1W—H1W0.8200C6—C71.382 (3)
O1W—H2W0.8200C6—H60.9300
O2W—H3W0.8200C7—H70.9300
O2W—H4W0.8200
O2Wi—Co1—O2W180.0O1—C1—O2126.42 (19)
O2Wi—Co1—O1Wi88.52 (7)O1—C1—C2119.1 (2)
O2W—Co1—O1Wi91.48 (7)O2—C1—C2114.4 (2)
O2Wi—Co1—O1W91.48 (7)C1—C2—S1111.63 (16)
O2W—Co1—O1W88.52 (7)C1—C2—H2A109.3
O1Wi—Co1—O1W180.0S1—C2—H2A109.3
O2Wi—Co1—N1i87.28 (7)C1—C2—H2B109.3
O2W—Co1—N1i92.72 (7)S1—C2—H2B109.3
O1Wi—Co1—N1i90.07 (6)H2A—C2—H2B108.0
O1W—Co1—N1i89.93 (6)N1—C3—C4123.78 (18)
O2Wi—Co1—N192.72 (7)N1—C3—H3118.1
O2W—Co1—N187.28 (7)C4—C3—H3118.1
O1Wi—Co1—N189.93 (6)C3—C4—C5119.23 (18)
O1W—Co1—N190.07 (6)C3—C4—H4120.4
N1i—Co1—N1180.0C5—C4—H4120.4
C5—S1—C2102.29 (10)C4—C5—C6117.35 (17)
Co1—O1W—H1W116.8C4—C5—S1125.34 (15)
Co1—O1W—H2W111.7C6—C5—S1117.27 (15)
H1W—O1W—H2W109.0C7—C6—C5119.40 (19)
Co1—O2W—H3W118.7C7—C6—H6120.3
Co1—O2W—H4W125.3C5—C6—H6120.3
H3W—O2W—H4W113.0N1—C7—C6123.38 (18)
C3—N1—C7116.71 (16)N1—C7—H7118.3
C3—N1—Co1122.00 (13)C6—C7—H7118.3
C7—N1—Co1120.65 (13)
O2Wi—Co1—N1—C359.79 (17)Co1—N1—C3—C4168.13 (16)
O2W—Co1—N1—C3120.21 (17)N1—C3—C4—C50.2 (3)
O1Wi—Co1—N1—C3148.31 (17)C3—C4—C5—C63.3 (3)
O1W—Co1—N1—C331.69 (17)C3—C4—C5—S1174.30 (16)
O2Wi—Co1—N1—C7129.63 (17)C2—S1—C5—C48.6 (2)
O2W—Co1—N1—C750.37 (17)C2—S1—C5—C6173.75 (17)
O1Wi—Co1—N1—C741.12 (17)C4—C5—C6—C73.5 (3)
O1W—Co1—N1—C7138.88 (17)S1—C5—C6—C7174.29 (18)
O1—C1—C2—S15.4 (3)C3—N1—C7—C62.6 (3)
O2—C1—C2—S1175.01 (16)Co1—N1—C7—C6168.50 (19)
C5—S1—C2—C1176.55 (15)C5—C6—C7—N10.6 (4)
C7—N1—C3—C42.8 (3)
Symmetry code: (i) x+1, y+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1W···O1ii0.822.052.849 (2)163
O1W—H2W···O1iii0.821.952.757 (2)167
O2W—H3W···O2iii0.821.912.725 (2)176
O2W—H4W···O2iv0.821.952.743 (2)163
Symmetry codes: (ii) x+2, y1/2, z+1/2; (iii) x+2, y+1, z+1; (iv) x1, y, z.

Experimental details

Crystal data
Chemical formula[Co(C7H6NO2S)2(H2O)4]
Mr467.37
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)12.173 (1), 10.479 (1), 7.523 (2)
β (°) 106.78 (3)
V3)918.8 (3)
Z2
Radiation typeMo Kα
µ (mm1)1.21
Crystal size (mm)0.45 × 0.40 × 0.30
Data collection
DiffractometerSiemens P4
diffractometer
Absorption correctionψ scan
(XEMP; Siemens, 1994)
Tmin, Tmax0.608, 0.684
No. of measured, independent and
observed [I > 2σ(I)] reflections
3491, 2651, 2283
Rint0.024
(sin θ/λ)max1)0.703
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.032, 0.102, 1.37
No. of reflections2651
No. of parameters125
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.41, 0.37

Computer programs: XSCANS (Siemens, 1994), XSCANS, SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), enCIFer (Allen et al., 2004).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1W···O1i0.822.052.849 (2)163.1
O1W—H2W···O1ii0.821.952.757 (2)167.1
O2W—H3W···O2ii0.821.912.725 (2)176.2
O2W—H4W···O2iii0.821.952.743 (2)162.8
Symmetry codes: (i) x+2, y1/2, z+1/2; (ii) x+2, y+1, z+1; (iii) x1, y, z.
 

Acknowledgements

We thank the Scientific Grant Agency of the Ministry of Education of the Slovak Republic and the Slovak Academy of Sciences (grant Nos. 1/4454/07 and 1/0353/08).

References

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