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Acta Cryst. (2008). E64, m797-m798    [ doi:10.1107/S1600536808011781 ]

Bis[hexaaquacobalt(II)] 25,26,27,28-tetrahydroxy-2,8,14,19-tetrathiacalix[4]arene-5,11,17,23-tetrasulfonate monohydrate

H. Akashi and M. Ichikawa

Abstract top

In the crystal structure of the title compound, [Co(H2O)6]2(C24H12O16S8)·H2O, the thiacalix[4]arenetetrasulfonate (= TCAS4-) anions adopt a cone-type conformation with an additional water molecule as a guest molecule in the hydrophobic cavity. The TCAS4- anions are arranged in layers in an up-down fashion. These anionic layers alternate with cationic layers consisting of rather regular octahedral cations (symmetry m). Several medium O-H...O hydrogen-bond interactions exist between the aqua ligands of the [Co(H2O)6]2+ cations and the O atoms of the sulfonate groups. In addition to the two crystallographically different Co atoms, two S and four O atoms are situated on mirror planes.

Comment top

The water soluble thiacalix[4]arene tetrasulfonate anion (= TCAS4-) is well-known as a second-sphere ligand of various transition metal coordination compounds containing complex metal aqua cations (Zhao, 2005). In the title compound, [Co(H2O)6]2(S8C24O16H12).H2O, (I), the second-sphere TCAS4- anionic ligands are linked to the aqua ligands of [Co(H2O)6] via several medium O-H···H hydrogen bonding interactions (see Table 2).

In the crystal structure of (I) the TCAS4- molecules adopt the cone-type conformation. The Co2+ ions are not directly bonded to the TCAS4- moieties, but exist as two octahedral aqua complexes, [Co(H2O)6]2+, both with m symmetry (Figure 1, Table 1). Layers of TCAS4- anions are arranged in an up-down fashion and alternate with cationic layers that contain the [Co(H2O)6]2+ cations (Figure 2).

The TCAS4- molecule include a water molecule as a guest-molecule in the hydrophobic cavity. Interactions between the H atoms of the aqua ligands of [Co(H2O)6]2+ and of O atoms of the TCAS4- moieties constitute a three-dimensional hydrogen bond network, and from there the second-sphere coordination is established.

Related literature top

For the structure of sodium thiacalix[4]arene tetrasulfonate hydrate, see: Akashi & Yamauchi (2003), and for the Cd salt of the same anion, see: Zhao et al. (2005). Assemblies of thiacalix[4]arene tetrasulfonates with several transition metal ions were described by Guo et al. (2004).

Experimental top

A solution of Na4(S8C24O16H12).14H2O (=Na4TCAS.14H2O) in 2 M HCl and a 2M HCl solution containing CoCl2.6H2O were mixed in the molar ratio (Co/Na4TCAS = 5), poured into a vial and stirred for 1 h. This solution was then kept at room temperature from which pale pink crystals of (I) were obtained within a few days. Elemental analysis of (I) is in agreement with the refined structure model. Found: C 24.85, H 2.89%; calculated for (I): C 24.74, H 3.29%.

Refinement top

Refinement was performed using 4296 reflections (5 < 2θ < 51°) out of 4319 independent reflections. The positions of all the H atoms were initially located from a difference map. All H atoms were refined by using the riding model approximation with C—H distances in the range 0.77–0.93Å. The isotropic displacement parameters for all H atoms were fixed at 1.2 times the value of the equivalent isotropic displacement parameter of their carrier atom. The H atoms attached to the water molecule in the hydrophobic cavity of thiacalix[4]arenetetrasulfonate could not be found from a difference map. Therefore the positions of the H atoms were not refined. The maximum of the remaining electron density is located 2.66Å away from atom O15.

Computing details top

Data collection: PROCESS-AUTO (Rigaku, 1998); cell refinement: PROCESS-AUTO (Rigaku, 1998); data reduction: CrystalStructure (Rigaku/MSC, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: CrystalStructure (Rigaku/MSC, 2006); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: CrystalStructure (Rigaku/MSC, 2006).

Figures top
[Figure 1] Fig. 1. The molecular entities of (I) with the atom-labelling scheme and displacement ellipsoids drawn at 50% probability level. Labelling of H atoms has been omitted for clarity. [Symmetry code: (i) x, 1/2 - y, z.]
[Figure 2] Fig. 2. The projection of the structure of (I) along the b axis.
Bis[hexaaquacobalt(II)] 25,26,27,28-tetrahydroxy-2,8,14,19- tetrathiacalix[4]arene-5,11,17,23-tetrasulfonate monohydrate top
Crystal data top
[Co(H2O)6]2(C24H12O16S8)·H2OF000 = 1192.00
Mr = 1164.89Dx = 1.788 Mg m−3
Monoclinic, P21/mMo Kα radiation
λ = 0.71069 Å
Hall symbol: -P 2ybCell parameters from 14562 reflections
a = 11.9955 (5) Åθ = 2.2–27.5º
b = 14.0628 (10) ŵ = 1.25 mm−1
c = 12.8907 (11) ÅT = 93 K
β = 95.638 (3)ºBlock, pale pink
V = 2164.0 (3) Å30.40 × 0.40 × 0.10 mm
Z = 2
Data collection top
Rigaku R-AXIS-IV
diffractometer		3640 reflections with F2 > 2σ(F2)
Detector resolution: 10.00 pixels mm-1Rint = 0.047
ω scansθmax = 25.5º
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)		h = −15→15
Tmin = 0.767, Tmax = 0.883k = −17→17
15194 measured reflectionsl = −16→16
4319 independent reflections
Refinement top
Refinement on F2H-atom parameters constrained
R[F2 > 2σ(F2)] = 0.044  w = 1/[0.0031Fo2 + σ(Fo2)]/(4Fo2)
wR(F2) = 0.144(Δ/σ)max < 0.001
S = 1.00Δρmax = 1.65 e Å−3
4296 reflectionsΔρmin = −0.81 e Å−3
320 parametersExtinction correction: none
Crystal data top
[Co(H2O)6]2(C24H12O16S8)·H2OV = 2164.0 (3) Å3
Mr = 1164.89Z = 2
Monoclinic, P21/mMo Kα
a = 11.9955 (5) ŵ = 1.25 mm−1
b = 14.0628 (10) ÅT = 93 K
c = 12.8907 (11) Å0.40 × 0.40 × 0.10 mm
β = 95.638 (3)º
Data collection top
Rigaku R-AXIS-IV
diffractometer		4319 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)		3640 reflections with F2 > 2σ(F2)
Tmin = 0.767, Tmax = 0.883Rint = 0.047
15194 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.044? restraints
wR(F2) = 0.144H-atom parameters constrained
S = 1.00Δρmax = 1.65 e Å−3
4296 reflectionsΔρmin = −0.81 e Å−3
320 parameters
Special details top

Refinement. Refinement was performed using 4296 reflections (5 < 2θ < 51°). The weighted R-factor (wR) and goodness of fit (S) are based on F2. R factor (gt) are based on F. The threshold expression of F2 > 2σ(F2) is used only for calculating R factor (gt).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Co10.04693 (6)0.25000.75294 (5)0.01428 (17)
Co20.00632 (6)0.25000.24647 (5)0.01639 (17)
S10.50722 (9)0.75000.56024 (9)0.0120 (2)
S20.53799 (7)0.47539 (6)0.25884 (6)0.01238 (19)
S30.52961 (10)0.7500−0.04805 (9)0.0129 (2)
S40.15582 (6)0.50788 (5)0.45489 (6)0.00843 (18)
S50.17521 (6)0.50752 (5)−0.03055 (6)0.00836 (18)
O10.60482 (18)0.64771 (18)0.38463 (19)0.0174 (5)
O20.61612 (19)0.64728 (17)0.14682 (18)0.0162 (5)
O30.10300 (19)0.50174 (16)0.34755 (17)0.0122 (5)
O40.10609 (19)0.58262 (17)0.51376 (17)0.0130 (5)
O50.15942 (19)0.41514 (16)0.50631 (17)0.0135 (5)
O60.1697 (2)0.50641 (16)−0.14431 (18)0.0132 (5)
O70.10106 (19)0.57942 (16)0.00710 (17)0.0121 (5)
O80.15982 (19)0.41379 (16)0.01357 (17)0.0117 (5)
O9−0.0351 (3)0.250000 (10)0.6031 (2)0.0206 (9)
O100.1310 (4)0.250000 (10)0.9006 (2)0.0393 (12)
O11−0.0636 (2)0.35446 (18)0.79486 (19)0.0257 (6)
O120.1547 (2)0.35660 (17)0.71050 (18)0.0184 (6)
O13−0.0660 (4)0.250000 (10)0.0934 (2)0.0380 (11)
O140.0769 (3)0.250000 (10)0.4013 (2)0.0178 (8)
O15−0.1064 (2)0.35324 (17)0.28526 (18)0.0201 (6)
O160.1180 (2)0.14395 (18)0.21098 (19)0.0240 (6)
O170.3199 (9)0.75000.2349 (9)0.154 (4)
C10.5066 (2)0.6116 (2)0.4082 (2)0.0123 (7)
C20.4618 (2)0.5311 (2)0.3545 (2)0.0107 (7)
C30.3575 (2)0.4978 (2)0.3728 (2)0.0113 (7)
C40.2960 (2)0.5438 (2)0.4440 (2)0.0103 (7)
C50.3419 (2)0.6201 (2)0.5015 (2)0.0107 (7)
C60.4478 (2)0.6531 (2)0.4843 (2)0.0102 (7)
C70.5189 (2)0.6115 (2)0.1034 (2)0.0114 (7)
C80.4647 (2)0.6537 (2)0.0126 (2)0.0098 (7)
C90.3610 (2)0.6200 (2)−0.0297 (2)0.0093 (7)
C100.3118 (2)0.5430 (2)0.0163 (2)0.0106 (7)
C110.3666 (2)0.4982 (2)0.1027 (2)0.0108 (7)
C120.4701 (2)0.5325 (2)0.1461 (2)0.0105 (7)
H10.33060.44700.33770.013*
H20.29960.64920.55100.013*
H30.32690.6542−0.09400.011*
H40.33800.44140.13150.013*
H50.61640.69940.40480.021*
H60.62720.63300.21330.020*
H7−0.05250.20400.56570.025*
H80.15290.29970.94500.046*
H9−0.08750.39560.75430.032*
H10−0.06480.37420.85010.031*
H110.15600.38060.64500.022*
H120.15560.40220.75020.022*
H13−0.07830.20550.05400.045*
H140.10570.29400.42860.021*
H15−0.12740.40020.24850.024*
H16−0.09960.38310.34500.024*
H170.11820.12570.15450.030*
H180.12170.09160.24200.030*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.0313 (4)0.0051 (3)0.0070 (3)0.00000.0045 (2)0.0000
Co20.0372 (4)0.0050 (3)0.0075 (3)0.00000.0052 (2)0.0000
S10.0131 (5)0.0110 (5)0.0113 (5)0.0000−0.0020 (4)0.0000
S20.0133 (3)0.0130 (4)0.0113 (3)0.0074 (2)0.0034 (3)0.0013 (2)
S30.0145 (5)0.0112 (5)0.0143 (5)0.00000.0088 (4)0.0000
S40.0107 (3)0.0076 (3)0.0075 (3)0.0005 (2)0.0029 (3)−0.0007 (2)
S50.0114 (3)0.0058 (3)0.0080 (3)0.0007 (2)0.0011 (3)−0.0010 (2)
O10.0095 (10)0.0191 (12)0.0240 (12)−0.0005 (9)0.0047 (10)0.0014 (10)
O20.0136 (10)0.0168 (12)0.0181 (11)−0.0003 (9)0.0001 (9)0.0011 (9)
O30.0180 (11)0.0100 (12)0.0089 (10)−0.0007 (8)0.0021 (9)−0.0004 (8)
O40.0146 (10)0.0111 (11)0.0142 (10)0.0021 (8)0.0063 (9)−0.0032 (8)
O50.0169 (11)0.0101 (11)0.0135 (10)−0.0003 (9)0.0009 (9)0.0023 (9)
O60.0186 (11)0.0106 (11)0.0100 (10)−0.0004 (9)−0.0007 (9)−0.0006 (8)
O70.0126 (10)0.0092 (11)0.0152 (10)0.0031 (8)0.0045 (9)−0.0004 (8)
O80.0167 (11)0.0077 (11)0.0104 (10)−0.0015 (8)0.0001 (9)0.0003 (8)
O90.042 (2)0.0102 (17)0.0094 (15)0.00000.0008 (15)0.0000
O100.095 (3)0.0078 (18)0.0115 (16)0.0000−0.015 (2)0.0000
O110.0573 (18)0.0121 (12)0.0094 (10)0.0091 (12)0.0126 (12)0.0010 (9)
O120.0365 (14)0.0086 (11)0.0108 (10)−0.0018 (10)0.0051 (10)−0.0022 (9)
O130.094 (3)0.0091 (18)0.0086 (15)0.0000−0.009 (2)0.0000
O140.034 (2)0.0075 (16)0.0118 (15)0.00000.0012 (15)0.0000
O150.0406 (15)0.0089 (11)0.0106 (10)0.0045 (10)0.0011 (11)−0.0006 (9)
O160.0523 (17)0.0089 (12)0.0132 (11)0.0059 (11)0.0150 (12)0.0015 (9)
O170.141 (9)0.149 (9)0.180 (10)0.00000.054 (8)0.0000
C10.0094 (13)0.0123 (16)0.0148 (14)0.0035 (12)−0.0011 (12)0.0048 (12)
C20.0150 (15)0.0087 (15)0.0084 (13)0.0059 (12)0.0009 (12)0.0008 (11)
C30.0148 (14)0.0095 (16)0.0098 (14)0.0032 (12)0.0016 (12)0.0002 (11)
C40.0133 (14)0.0071 (15)0.0110 (13)−0.0002 (11)0.0031 (12)0.0023 (11)
C50.0133 (14)0.0090 (15)0.0103 (14)0.0042 (11)0.0040 (12)0.0007 (11)
C60.0132 (14)0.0076 (14)0.0092 (13)0.0026 (11)−0.0019 (12)−0.0006 (11)
C70.0091 (13)0.0132 (16)0.0124 (14)0.0043 (12)0.0038 (12)−0.0030 (12)
C80.0114 (14)0.0091 (15)0.0103 (13)0.0006 (11)0.0075 (12)0.0006 (11)
C90.0101 (13)0.0091 (15)0.0088 (13)0.0005 (11)0.0008 (12)−0.0016 (11)
C100.0128 (14)0.0070 (15)0.0123 (13)0.0026 (11)0.0031 (12)−0.0004 (11)
C110.0175 (15)0.0078 (15)0.0077 (13)0.0030 (12)0.0040 (13)−0.0013 (11)
C120.0129 (14)0.0092 (15)0.0097 (13)0.0070 (11)0.0027 (12)−0.0008 (11)
Geometric parameters (Å, °) top
Co1—O92.079 (3)C3—C41.392 (4)
Co1—O102.064 (3)C4—C51.386 (4)
Co1—O112.085 (2)C5—C61.390 (4)
Co1—O11i2.085 (2)C7—C81.413 (4)
Co1—O122.088 (2)C7—C121.393 (4)
Co1—O12i2.088 (2)C8—C91.391 (4)
Co2—O132.076 (3)C9—C101.394 (4)
Co2—O142.090 (3)C10—C111.387 (4)
Co2—O152.078 (2)C11—C121.397 (4)
Co2—O15i2.078 (2)O1—H50.779
Co2—O162.085 (2)O2—H60.878
Co2—O16i2.085 (2)O9—H70.822
S1—C61.786 (3)O9—H7i0.822
S1—C6ii1.786 (3)O10—H80.925
S2—C21.786 (3)O10—H8i0.925
S2—C121.785 (3)O11—H90.813
S3—C81.781 (3)O11—H100.766
S3—C8ii1.781 (3)O12—H110.911
S4—O31.467 (2)O12—H120.820
S4—O41.458 (2)O13—H130.811
S4—O51.462 (2)O13—H13i0.811
S4—C41.775 (3)O14—H140.776
S5—O61.462 (2)O14—H14i0.776
S5—O71.461 (2)O15—H150.837
S5—O81.455 (2)O15—H160.874
S5—C101.762 (3)O16—H170.772
O1—C11.345 (3)O16—H180.837
O2—C71.341 (3)C3—H10.888
C1—C21.406 (4)C5—H20.947
C1—C61.392 (4)C9—H31.009
C2—C31.378 (4)C11—H40.958
O9—Co1—O10179.01 (18)C3—C4—C5120.3 (2)
O9—Co1—O1189.19 (10)C4—C5—C6119.6 (2)
O9—Co1—O11i89.19 (10)S1—C6—C1120.2 (2)
O9—Co1—O1290.31 (10)S1—C6—C5119.3 (2)
O9—Co1—O12i90.31 (10)C1—C6—C5120.4 (2)
O10—Co1—O1191.51 (12)O2—C7—C8119.9 (2)
O10—Co1—O11i91.51 (12)O2—C7—C12121.1 (2)
O10—Co1—O1289.00 (12)C8—C7—C12119.0 (2)
O10—Co1—O12i89.00 (12)S3—C8—C7119.9 (2)
O11—Co1—O11i89.58 (11)S3—C8—C9119.9 (2)
O11—Co1—O1289.31 (10)C7—C8—C9120.2 (2)
O11—Co1—O12i178.79 (10)C8—C9—C10119.8 (2)
O11i—Co1—O12178.79 (10)S5—C10—C9119.5 (2)
O11i—Co1—O12i89.31 (10)S5—C10—C11119.8 (2)
O12—Co1—O12i91.80 (10)C9—C10—C11120.5 (2)
O13—Co2—O14179.19 (18)C10—C11—C12119.8 (2)
O13—Co2—O1590.44 (12)S2—C12—C7120.3 (2)
O13—Co2—O15i90.44 (12)S2—C12—C11119.1 (2)
O13—Co2—O1690.52 (12)C7—C12—C11120.5 (2)
O13—Co2—O16i90.52 (12)C1—O1—H5114.1
O14—Co2—O1588.99 (9)C7—O2—H6111.3
O14—Co2—O15i88.99 (9)Co1—O9—H7128.0
O14—Co2—O1690.04 (10)Co1—O9—H7i128.0
O14—Co2—O16i90.04 (10)H7—O9—H7i103.8
O15—Co2—O15i88.64 (10)Co1—O10—H8130.8
O15—Co2—O16178.36 (10)Co1—O10—H8i130.8
O15—Co2—O16i90.02 (10)H8—O10—H8i98.2
O15i—Co2—O1690.02 (10)Co1—O11—H9121.8
O15i—Co2—O16i178.36 (10)Co1—O11—H10124.5
O16—Co2—O16i91.31 (10)H9—O11—H10107.6
C6—S1—C6ii99.56 (15)Co1—O12—H11125.2
C2—S2—C1298.15 (14)Co1—O12—H12111.6
C8—S3—C8ii99.04 (15)H11—O12—H12106.7
O3—S4—O4111.87 (13)Co2—O13—H13129.0
O3—S4—O5111.47 (12)Co2—O13—H13i129.0
O3—S4—C4105.50 (14)H13—O13—H13i101.1
O4—S4—O5113.74 (13)Co2—O14—H14123.7
O4—S4—C4105.98 (14)Co2—O14—H14i123.7
O5—S4—C4107.68 (13)H14—O14—H14i105.7
O6—S5—O7111.83 (13)Co2—O15—H15125.6
O6—S5—O8112.81 (13)Co2—O15—H16122.8
O6—S5—C10107.21 (14)H15—O15—H1696.7
O7—S5—O8113.11 (13)Co2—O16—H17120.4
O7—S5—C10105.42 (14)Co2—O16—H18121.9
O8—S5—C10105.79 (14)H17—O16—H1898.9
O1—C1—C2119.6 (2)C2—C3—H1118.5
O1—C1—C6121.1 (2)C4—C3—H1121.3
C2—C1—C6119.2 (2)C4—C5—H2118.9
S2—C2—C1119.7 (2)C6—C5—H2121.4
S2—C2—C3120.2 (2)C8—C9—H3115.8
C1—C2—C3120.0 (2)C10—C9—H3124.4
C2—C3—C4120.2 (2)C10—C11—H4122.0
S4—C4—C3119.1 (2)C12—C11—H4118.1
S4—C4—C5120.5 (2)
Symmetry codes: (i) x, −y+1/2, z; (ii) x, −y+3/2, z.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H5···O1ii0.782.172.877 (3)151
O2—H6···O10.882.263.082 (3)156
O2—H6···O12iii0.882.713.154 (3)113
O9—H7···O4iv0.822.062.878 (3)173
O9—H7···O4iv0.822.062.878 (3)173
O10—H8···O8v0.931.832.729 (2)163
O10—H8···O8v0.931.832.729 (2)163
O11—H9···O3vi0.811.952.741 (3)165
O11—H10···O7vi0.772.042.795 (3)169
O12—H11···O50.911.862.764 (3)173
O12—H12···O6v0.822.002.812 (3)174
O13—H13···O7vii0.811.952.739 (2)165
O13—H13···O7vii0.811.952.739 (2)165
O14—H14···O50.782.052.818 (2)172
O14—H14···O50.782.052.818 (2)172
O15—H15···O6viii0.841.912.739 (3)170
O15—H16···O4vi0.871.892.743 (3)164
O16—H17···O8ix0.772.012.764 (3)166
O16—H18···O3ix0.841.922.719 (3)159
Symmetry codes: (ii) x, −y+3/2, z; (iii) −x+1, −y+1, −z+1; (iv) −x, y−1/2, −z+1; (v) x, y, z+1; (vi) −x, −y+1, −z+1; (vii) −x, y−1/2, −z; (viii) −x, −y+1, −z; (ix) x, −y+1/2, z.
Table 1
Selected geometric parameters (Å) top
Co1—O92.079 (3)Co2—O132.076 (3)
Co1—O102.064 (3)Co2—O142.090 (3)
Co1—O112.085 (2)Co2—O152.078 (2)
Co1—O122.088 (2)Co2—O162.085 (2)
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H5···O1i0.782.172.877 (3)151
O2—H6···O10.882.263.082 (3)156
O2—H6···O12ii0.882.713.154 (3)113
O9—H7···O4iii0.822.062.878 (3)173
O9—H7···O4iii0.822.062.878 (3)173
O10—H8···O8iv0.931.832.729 (2)163
O10—H8···O8iv0.931.832.729 (2)163
O11—H9···O3v0.811.952.741 (3)165
O11—H10···O7v0.772.042.795 (3)169
O12—H11···O50.911.862.764 (3)173
O12—H12···O6iv0.822.002.812 (3)174
O13—H13···O7vi0.811.952.739 (2)165
O13—H13···O7vi0.811.952.739 (2)165
O14—H14···O50.782.052.818 (2)172
O14—H14···O50.782.052.818 (2)172
O15—H15···O6vii0.841.912.739 (3)170
O15—H16···O4v0.871.892.743 (3)164
O16—H17···O8viii0.772.012.764 (3)166
O16—H18···O3viii0.841.922.719 (3)159
Symmetry codes: (i) x, −y+3/2, z; (ii) −x+1, −y+1, −z+1; (iii) −x, y−1/2, −z+1; (iv) x, y, z+1; (v) −x, −y+1, −z+1; (vi) −x, y−1/2, −z; (vii) −x, −y+1, −z; (viii) x, −y+1/2, z.
Acknowledgements top

This research was partially supported by the Ministry of Education, Science, Sports and Culture, Grant-in-Aid for Scientific Research, 18550063, 2007.

references
References top

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