supplementary materials


tk5188 scheme

Acta Cryst. (2013). E69, m97    [ doi:10.1107/S1600536813000196 ]

[[mu]-6,9-Bis(carboxylatomethyl)-3,12-bis(carboxymethyl)-3,6,9,12-tetraazatetradecanedioato]bis[aquacobalt(II)] tetrahydrate

Q. Qian, J. Wu and J. Qian

Abstract top

The binuclear title complex, [Co2(C18H26N4O12)(H2O)2]·4H2O, lies about a centre of inversion, the CoII atom being coordinated in a distorted octahedral arrangement defined by one water molecule and N2O3 donors derived from one end of a 6,9-bis(carboxylatomethyl)-3,12-bis(carboxymethyl)-3,6,9,12-tetraazatetradecanedioate (H2TTHA4-) tetraanion. In the crystal, numerous O-H...O hydrogen bonds link the molecules into a three-dimensional network.

Comment top

H6TTHA (triethylenetetraminehexaacetic acid) is a multicarboxyl ligand with ten potential coordinating sites and plays an important role in the self-assembly of various functional materials (Xu et al., 2008; Ouyang et al., 2007). In an effort to explore new enzyme-mimics involved with cobalt(II) and poly-carboxyl-group ligands, we have synthesized and crystallized the title complex, [Co2(H2TTHA)(H2O)2].4H2O, (I), in water under ambient conditions via the reaction of Co(OH)2 and H6TTHA. Herein, we report its crystal structure.

The asymmetric unit of (I) comprises half a neutral [Co2(H2TTHA)(H2O)2] binuclear unit and two solvent water molecules (Fig. 1). The binuclear [Co2(H2TTHA)(H2O)2] is centrosymmetric with the midpoint of the ethylene C—C bond on an inversion centre. Each CoII ion has a distorted octahedral geometry and is bonded to two N atoms and three carboxylate-O atoms from half of the H2TTHA4- ligand, as well as a water molecule. The Co1—N1 and Co1—N2 bond lengths are 2.216 (3) and 2.134 (3) Å, respectively, and the Co—O bond lengths range from 2.031 (3) to 2.120 (3) Å which are similar to those in its analogous structure (Song et al., 2003)

Analysis indicates (Spek, 2009) that in the crystal packing there are extensive O—H···O hydrogen-bond interactions (Table 1) between the O atoms of the six carboxylate/carboxylic acid groups of the H2TTHA4- ligand and/or the water molecules, leading to a three-dimensional array (Fig. 2).

Related literature top

For related coordination complexes of species derived from triethylenetetraminehexaacetic acid, see: Ouyang et al. (2007); Xu et al. (2008). For a related structure, see: Song et al. (2003).

Experimental top

A mixture of Co(OH)2 (0.18 g, 2 mmol) and H6TTHA (0.20 g, 0.5 mmol) was stirred in H2O (30 ml) solution for 30 min at room temperature. The resulting solution was filtered and the clear solution was left standing for two weeks. Purple crystals of (I) suitable for X-ray diffraction were obtained at the bottom of the vessel.

Refinement top

C-bound H atoms were positioned geometrically (C—H = 0.97 Å) and refined with Uiso= 1.2Ueq(carrier atom). The carboxyl H1 and H5 atoms are each located close to a crystallographic inversion centre between pairs of symmetry equivalent atoms of O1 and O5. Both H atoms were thus refined as 50% occupied. The O—H distances were constrained to be 0.82 Å and Uiso= 1.5Ueq(O). Water H atoms were initially found in a difference map and refined with O—H = 0.82 Å and Uiso= 1.5Ueq(O). Several reflections, i.e. (0 0 1), (0 1 0), (2 0 0) and (-4 3 2), were omitted from the refinement owing to poor agreement.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structures of the components of (I) with displacement ellipsoids drawn at the 50% probability level. Unlabelled atoms are related by the symmetry operation: 2-x, 1-y, 1-z.
[Figure 2] Fig. 2. Part of the crystal structure of (I), showing the formation of a three-dimensional network by hydrogen bonds (dashed lines). Hydrogen atoms not involved in hydrogen bonding have been omitted for clarity.
[µ-6,9-Bis(carboxylatomethyl)-3,12-bis(carboxymethyl)-3,6,9,12- tetraazatetradecanedioato]bis[aquacobalt(II)] tetrahydrate top
Crystal data top
[Co2(C18H26N4O12)(H2O)2]·4H2OZ = 1
Mr = 716.38F(000) = 372
Triclinic, P1Dx = 1.742 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.0972 (15) ÅCell parameters from 1506 reflections
b = 8.7025 (19) Åθ = 2.6–23.8°
c = 11.968 (3) ŵ = 1.31 mm1
α = 104.238 (4)°T = 292 K
β = 100.986 (3)°Plate, violet
γ = 100.425 (4)°0.10 × 0.08 × 0.05 mm
V = 682.9 (3) Å3
Data collection top
Bruker SMART APEX CCD
diffractometer
3099 independent reflections
Radiation source: fine focus sealed Siemens Mo tube2182 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.097
0.3° wide ω exposures scansθmax = 27.5°, θmin = 2.6°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008)
h = 99
Tmin = 0.881, Tmax = 0.938k = 1111
8012 measured reflectionsl = 1515
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)] = 0.053Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.117H-atom parameters constrained
S = 0.94 w = 1/[σ2(Fo2) + (0.047P)2]
where P = (Fo2 + 2Fc2)/3
3099 reflections(Δ/σ)max < 0.001
190 parametersΔρmax = 0.61 e Å3
0 restraintsΔρmin = 0.53 e Å3
Crystal data top
[Co2(C18H26N4O12)(H2O)2]·4H2Oγ = 100.425 (4)°
Mr = 716.38V = 682.9 (3) Å3
Triclinic, P1Z = 1
a = 7.0972 (15) ÅMo Kα radiation
b = 8.7025 (19) ŵ = 1.31 mm1
c = 11.968 (3) ÅT = 292 K
α = 104.238 (4)°0.10 × 0.08 × 0.05 mm
β = 100.986 (3)°
Data collection top
Bruker SMART APEX CCD
diffractometer
3099 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008)
2182 reflections with I > 2σ(I)
Tmin = 0.881, Tmax = 0.938Rint = 0.097
8012 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.053H-atom parameters constrained
wR(F2) = 0.117Δρmax = 0.61 e Å3
S = 0.94Δρmin = 0.53 e Å3
3099 reflectionsAbsolute structure: ?
190 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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*/UeqOcc. (<1)
Co10.72982 (7)0.71114 (6)0.70687 (4)0.02486 (17)
N10.9888 (4)0.6394 (4)0.6502 (2)0.0260 (7)
N20.9015 (4)0.9540 (4)0.7434 (2)0.0255 (7)
O11.0763 (4)0.5057 (4)0.9155 (2)0.0457 (8)
H11.02400.51530.97150.069*0.50
O20.8739 (4)0.6544 (3)0.8584 (2)0.0306 (6)
O30.6757 (5)0.9168 (4)0.4387 (2)0.0548 (9)
O40.6154 (4)0.7492 (3)0.5486 (2)0.0308 (6)
O50.6500 (4)1.0653 (3)0.9745 (2)0.0401 (7)
H50.54491.01840.98300.060*0.50
O60.5890 (4)0.8431 (3)0.8222 (2)0.0335 (6)
O70.5376 (4)0.4898 (3)0.6630 (2)0.0416 (7)
H7A0.57790.42740.69780.062*
H7B0.51430.43170.59430.062*
C10.9172 (5)0.5213 (5)0.5288 (3)0.0322 (9)
H1A0.83420.56700.47810.039*
H1B0.83620.42170.53340.039*
C21.0911 (6)0.5704 (5)0.7386 (3)0.0395 (10)
H2A1.22920.62860.76570.047*
H2B1.08510.45700.70040.047*
C31.0033 (6)0.5803 (5)0.8454 (3)0.0302 (9)
C41.1120 (6)0.7947 (5)0.6468 (3)0.0313 (9)
H4A1.06300.81540.57190.038*
H4B1.24720.78520.65180.038*
C51.1076 (6)0.9363 (5)0.7487 (3)0.0351 (10)
H5A1.16220.91810.82370.042*
H5B1.18871.03620.74460.042*
C60.8262 (6)1.0170 (5)0.6438 (3)0.0362 (10)
H6A0.93771.07450.62240.043*
H6B0.75071.09500.67060.043*
C70.6972 (6)0.8852 (5)0.5344 (3)0.0330 (9)
C80.8807 (6)1.0525 (5)0.8581 (3)0.0310 (9)
H8A0.88291.16320.85540.037*
H8B0.99121.05650.92150.037*
C90.6896 (6)0.9799 (5)0.8838 (3)0.0284 (8)
O80.5622 (5)0.2722 (4)0.7785 (3)0.0729 (11)
H8C0.58550.31760.85010.109*
H8D0.44410.23020.76580.109*
O90.3797 (6)0.3141 (5)0.9602 (4)0.1021 (15)
H9A0.37220.29691.02370.153*
H9B0.28450.35200.94180.153*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.0255 (3)0.0292 (3)0.0196 (3)0.0075 (2)0.0068 (2)0.0049 (2)
N10.0287 (17)0.0341 (18)0.0182 (15)0.0108 (14)0.0098 (13)0.0076 (13)
N20.0281 (17)0.0298 (17)0.0190 (15)0.0065 (14)0.0094 (13)0.0057 (13)
O10.055 (2)0.068 (2)0.0344 (16)0.0356 (17)0.0201 (15)0.0306 (16)
O20.0338 (15)0.0446 (17)0.0198 (13)0.0194 (13)0.0112 (12)0.0102 (12)
O30.077 (2)0.055 (2)0.0289 (16)0.0015 (17)0.0066 (16)0.0207 (15)
O40.0358 (16)0.0321 (15)0.0222 (13)0.0067 (12)0.0031 (12)0.0077 (12)
O50.0412 (17)0.0452 (18)0.0286 (15)0.0088 (14)0.0185 (13)0.0050 (13)
O60.0301 (15)0.0372 (16)0.0306 (15)0.0082 (13)0.0126 (12)0.0010 (13)
O70.0489 (18)0.0369 (17)0.0311 (16)0.0011 (14)0.0062 (14)0.0051 (13)
C10.033 (2)0.034 (2)0.030 (2)0.0091 (18)0.0158 (18)0.0037 (18)
C20.045 (3)0.057 (3)0.031 (2)0.029 (2)0.018 (2)0.021 (2)
C30.031 (2)0.037 (2)0.0220 (19)0.0077 (18)0.0068 (17)0.0078 (17)
C40.027 (2)0.035 (2)0.031 (2)0.0057 (17)0.0105 (17)0.0063 (18)
C50.027 (2)0.039 (2)0.033 (2)0.0019 (18)0.0085 (18)0.0038 (19)
C60.051 (3)0.032 (2)0.026 (2)0.0106 (19)0.0110 (19)0.0079 (18)
C70.036 (2)0.041 (2)0.025 (2)0.0128 (19)0.0092 (18)0.0110 (18)
C80.036 (2)0.032 (2)0.0201 (19)0.0051 (18)0.0072 (17)0.0009 (16)
C90.030 (2)0.033 (2)0.0223 (19)0.0117 (18)0.0046 (17)0.0078 (17)
O80.073 (3)0.077 (3)0.064 (2)0.005 (2)0.010 (2)0.027 (2)
O90.121 (4)0.106 (4)0.115 (4)0.058 (3)0.069 (3)0.043 (3)
Geometric parameters (Å, º) top
Co1—O72.031 (3)C1—C1i1.527 (7)
Co1—O42.043 (2)C1—H1A0.9700
Co1—O62.094 (2)C1—H1B0.9700
Co1—O22.120 (2)C2—C31.516 (5)
Co1—N22.134 (3)C2—H2A0.9700
Co1—N12.216 (3)C2—H2B0.9700
N1—C21.477 (4)C4—C51.515 (5)
N1—C41.486 (4)C4—H4A0.9700
N1—C11.490 (4)C4—H4B0.9700
N2—C81.478 (4)C5—H5A0.9700
N2—C61.480 (4)C5—H5B0.9700
N2—C51.490 (5)C6—C71.514 (5)
O1—C31.272 (4)C6—H6A0.9700
O1—H10.8200C6—H6B0.9700
O2—C31.226 (4)C8—C91.509 (5)
O3—C71.230 (4)C8—H8A0.9700
O4—C71.286 (4)C8—H8B0.9700
O5—C91.267 (4)O8—H8D0.8200
O5—H50.8200O8—H8C0.8200
O6—C91.237 (4)O8—H8D0.8200
O7—H7A0.8201O9—H9A0.8200
O7—H7B0.8200O9—H9B0.8200
O7—Co1—O492.28 (11)N1—C2—H2A108.9
O7—Co1—O697.80 (11)C3—C2—H2A108.9
O4—Co1—O6102.38 (10)N1—C2—H2B108.9
O7—Co1—O287.25 (11)C3—C2—H2B108.9
O4—Co1—O2172.02 (10)H2A—C2—H2B107.7
O6—Co1—O285.56 (10)O2—C3—O1125.6 (3)
O7—Co1—N2172.89 (11)O2—C3—C2120.8 (3)
O4—Co1—N282.40 (11)O1—C3—C2113.6 (3)
O6—Co1—N278.85 (11)N1—C4—C5111.0 (3)
O2—Co1—N298.68 (11)N1—C4—H4A109.4
O7—Co1—N1100.97 (11)C5—C4—H4A109.4
O4—Co1—N193.72 (10)N1—C4—H4B109.4
O6—Co1—N1154.68 (11)C5—C4—H4B109.4
O2—Co1—N178.57 (10)H4A—C4—H4B108.0
N2—Co1—N184.15 (11)N2—C5—C4110.7 (3)
C2—N1—C4112.2 (3)N2—C5—H5A109.5
C2—N1—C1112.8 (3)C4—C5—H5A109.5
C4—N1—C1110.5 (3)N2—C5—H5B109.5
C2—N1—Co1108.9 (2)C4—C5—H5B109.5
C4—N1—Co1103.8 (2)H5A—C5—H5B108.1
C1—N1—Co1108.1 (2)N2—C6—C7113.7 (3)
C8—N2—C6111.9 (3)N2—C6—H6A108.8
C8—N2—C5112.3 (3)C7—C6—H6A108.8
C6—N2—C5111.7 (3)N2—C6—H6B108.8
C8—N2—Co1108.2 (2)C7—C6—H6B108.8
C6—N2—Co1107.5 (2)H6A—C6—H6B107.7
C5—N2—Co1104.7 (2)O3—C7—O4124.8 (4)
C3—O1—H1109.5O3—C7—C6117.7 (4)
C3—O2—Co1116.4 (2)O4—C7—C6117.5 (3)
C7—O4—Co1115.5 (2)N2—C8—C9110.6 (3)
C9—O5—H5109.5N2—C8—H8A109.5
C9—O6—Co1114.6 (2)C9—C8—H8A109.5
Co1—O7—H7A113.6N2—C8—H8B109.5
Co1—O7—H7B117.3C9—C8—H8B109.5
H7A—O7—H7B99.1H8A—C8—H8B108.1
N1—C1—C1i113.9 (4)O6—C9—O5124.5 (4)
N1—C1—H1A108.8O6—C9—C8120.5 (3)
C1i—C1—H1A108.8O5—C9—C8114.9 (3)
N1—C1—H1B108.8H8D—O8—H8C99.3
C1i—C1—H1B108.8H8C—O8—H8D99.3
H1A—C1—H1B107.7H9A—O9—H9B104.7
N1—C2—C3113.2 (3)
O7—Co1—N1—C276.1 (3)O4—Co1—O6—C999.2 (3)
O4—Co1—N1—C2169.1 (2)O2—Co1—O6—C980.1 (3)
O6—Co1—N1—C261.1 (4)N2—Co1—O6—C919.6 (3)
O2—Co1—N1—C28.8 (2)N1—Co1—O6—C929.1 (4)
N2—Co1—N1—C2108.9 (3)C2—N1—C1—C1i67.4 (5)
O7—Co1—N1—C4164.2 (2)C4—N1—C1—C1i59.1 (5)
O4—Co1—N1—C471.1 (2)Co1—N1—C1—C1i172.2 (4)
O6—Co1—N1—C458.6 (3)C4—N1—C2—C3109.8 (4)
O2—Co1—N1—C4110.9 (2)C1—N1—C2—C3124.6 (3)
N2—Co1—N1—C410.8 (2)Co1—N1—C2—C34.6 (4)
O7—Co1—N1—C146.8 (2)Co1—O2—C3—O1164.1 (3)
O4—Co1—N1—C146.3 (2)Co1—O2—C3—C215.6 (5)
O6—Co1—N1—C1176.0 (2)N1—C2—C3—O26.9 (5)
O2—Co1—N1—C1131.7 (2)N1—C2—C3—O1172.8 (3)
N2—Co1—N1—C1128.2 (2)C2—N1—C4—C579.2 (4)
O4—Co1—N2—C8127.7 (2)C1—N1—C4—C5154.0 (3)
O6—Co1—N2—C823.4 (2)Co1—N1—C4—C538.2 (3)
O2—Co1—N2—C860.3 (2)C8—N2—C5—C4161.8 (3)
N1—Co1—N2—C8137.7 (2)C6—N2—C5—C471.5 (4)
O4—Co1—N2—C66.6 (2)Co1—N2—C5—C444.6 (3)
O6—Co1—N2—C697.7 (2)N1—C4—C5—N259.1 (4)
O2—Co1—N2—C6178.6 (2)C8—N2—C6—C7134.5 (3)
N1—Co1—N2—C6101.2 (2)C5—N2—C6—C798.6 (4)
O4—Co1—N2—C5112.3 (2)Co1—N2—C6—C715.7 (4)
O6—Co1—N2—C5143.4 (2)Co1—O4—C7—O3165.6 (3)
O2—Co1—N2—C559.7 (2)Co1—O4—C7—C615.6 (4)
N1—Co1—N2—C517.8 (2)N2—C6—C7—O3159.4 (4)
O7—Co1—O2—C388.1 (3)N2—C6—C7—O421.6 (5)
O6—Co1—O2—C3173.8 (3)C6—N2—C8—C993.7 (4)
N2—Co1—O2—C395.8 (3)C5—N2—C8—C9139.8 (3)
N1—Co1—O2—C313.7 (3)Co1—N2—C8—C924.7 (3)
O7—Co1—O4—C7179.9 (3)Co1—O6—C9—O5165.2 (3)
O6—Co1—O4—C781.6 (3)Co1—O6—C9—C810.9 (4)
N2—Co1—O4—C74.8 (3)N2—C8—C9—O610.2 (5)
N1—Co1—O4—C778.8 (3)N2—C8—C9—O5173.3 (3)
O7—Co1—O6—C9166.7 (3)
Symmetry code: (i) x+2, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O1ii0.821.682.483 (5)168
O5—H5···O5iii0.821.672.481 (5)170
O7—H7A···O80.821.842.616 (4)157
O7—H7B···O4iv0.821.952.732 (4)159
O8—H8D···O3iv0.822.372.745 (5)109
O8—H8C···O90.822.152.719 (5)127
O9—H9A···O2v0.822.483.067 (4)130
O9—H9A···O6v0.822.453.217 (5)157
Symmetry codes: (ii) x+2, y+1, z+2; (iii) x+1, y+2, z+2; (iv) x+1, y+1, z+1; (v) x+1, y+1, z+2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O1i0.821.682.483 (5)168
O5—H5···O5ii0.821.672.481 (5)170
O7—H7A···O80.821.842.616 (4)157
O7—H7B···O4iii0.821.952.732 (4)159
O8—H8D···O3iii0.822.372.745 (5)109
O8—H8C···O90.822.152.719 (5)127
O9—H9A···O2iv0.822.483.067 (4)130
O9—H9A···O6iv0.822.453.217 (5)157
Symmetry codes: (i) x+2, y+1, z+2; (ii) x+1, y+2, z+2; (iii) x+1, y+1, z+1; (iv) x+1, y+1, z+2.
Acknowledgements top

We thank Henan University for providing the structural data for the title complex.

references
References top

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