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Acta Cryst. (2009). E65, m1165    [ doi:10.1107/S160053680903428X ]

Poly[[[mu]2-1,4-bis(imidazol-1-ylmethyl)benzene]bis([mu]4-cyclohexane-1,4-dicarboxylato)dicobalt(II)]

Q.-D. Yu, D.-J. Sun and E. R. T. Tiekink

Abstract top

In the title compound, [Co2(C8H10O4)2(C14H14N4)]n, the two CoII atoms are both five-coordinated by four carboxylate O atoms, derived from two different cyclohexane-1,4-dicarboxylate (chdc) ligands, and an N atom, derived from one end of a 1,4-bis(imidazol-1-ylmethyl)benzene molecule (1,4-bix), in a distorted square-pyramidal environment. Each end of the chdc ligand links pairs of CoII atoms into a paddle-wheel assembly, i.e. Co2(O2CR')4; these are connected into rows because of the bridging nature of the chdc ligands, and the rows are further connected into a two-dimensional layer through the 1,4-bix ligands. The 1,4-bix ligand, which is disposed about a centre of inversion, is disorderd. Two positions were discerned for the -CH2(C6H4)CH2- residue, with the major component having a site-occupancy factor of 0.512 (9).

Comment top

So far, the rigid N-containing bridging ligand, such as 4,4'-bipyridine, has been widely used in the construction of metal-organic polymers, however, the flexible N-donor ligand, such as 1,4-bis(imidazol-1-ylmethyl)benzene (1,4-bix), has not been well studied (Yang et al., 2008). In this work, 1,4-bix assembles with cobalt cyclohexane-1,4-dicarboxylate (chdc) to give a two-dimensional polymer [Co2(chdc)2(1,4-bix)] (I).

The compound (I) is isostructural with reported Ni(II) compound (Li et al., 2009). The asymmetric unit of (I) comprises a Co atom, a chdc dianion, and half a 1, 4-bix molecule which is disposed about a centre of inversion (Fig. 1). Each CoII atom is five-coordinated by four carboxylate O atoms, derived from two different chdc ligands, and an N atom, derived from one end of a 1,4-bix molecule, in distorted square pyramidal sphere. Each end of the chdc ligand links pairs of CoII atoms into a paddle-wheel assembly, i.e. Co2(O2CR')4. These are connected into rows because of the bridging nature of the chdc ligands, and rows are further connected into a two-dimensional layer through the 1,4-bix ligands. If the second Co atom in the paddle-wheel assembly is considered as occupying a coordination site, the Co···Co distance is 2.721 (6) Å, the coordination geometry would be distorted octahedral.

Related literature top

For background to coordination polymers, see: Yang et al. (2008). For the isomorphous Ni(II) structure, see: Li et al. (2009).

Experimental top

H2chdc (0.5 mmol), 1,4-bix (0.5 mmol) and cobalt chloride hexahydrate (0.5 mmol) were placed in water (15 ml), and triethylamine was added until the pH value of the solution was 5.6. The solution was heated in a 23 ml Teflon-lined stainless-steel autoclave at 445 K for 3 days. The autoclave was cooled to room temperature over several hours. Purple crystals were isolated in about 52% yield.

Refinement top

Carbon-bound H-atoms were placed in calculated positions with C—H = 0.93 - 0.98 Å, and were included in the refinement in the riding model approximation, with U(H) set to 1.2Ueq(C).

Disorder was noted in bridging 1,4-bix ligand. Two positions were discerned for the -H2C(C6H4)CH2- residue. From refinement, the major component had a site occupancy of 0.512 (9). Multiple positions were not resolved for the imidazole ring, even though several of the atoms exhibited elongated displacement ellipsoids. The atoms of this ring were restrained to be approximately isotropic with application of the ISOR command in SHELXL-97 (Sheldrick, 2008).

The maximum and minimum residual electron density peaks of 1.34 and -1.40 eÅ-3, respectively, were located 0.08 Å and 0.05 Å from the N1 and N2 atoms, respectively.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SMART (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The asymmetric unit in the polymeric structure of (I), showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. Only one component of the disordered -CH2(C6H4)CH2- residue is shown for reasons of clarity.
[Figure 2] Fig. 2. View of the two-dimensional layer in (I). H atoms have been omitted for clarity.
Poly[[µ2-1,4-bis(imidazol-1-ylmethyl)benzene]bis(µ4-cyclohexane-1,4- dicarboxylato)dicobalt(II)] top
Crystal data top
[Co2(C8H10O4)2(C14H14N4)]Z = 1
Mr = 696.48F(000) = 360
Triclinic, P1Dx = 1.516 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.5415 (6) ÅCell parameters from 2663 reflections
b = 8.8051 (5) Åθ = 3.0–25.0°
c = 10.8007 (5) ŵ = 1.14 mm−1
α = 93.824 (4)°T = 293 K
β = 100.940 (4)°Block, purple
γ = 105.413 (5)°0.24 × 0.22 × 0.21 mm
V = 762.95 (8) Å3
Data collection top
Bruker APEX
diffractometer		2663 independent reflections
Radiation source: fine-focus sealed tube2212 reflections with I > 2σ(I)
graphiteRint = 0.030
φ and ω scansθmax = 25.0°, θmin = 4.3°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −9→10
Tmin = 0.756, Tmax = 0.788k = −10→10
6296 measured reflectionsl = −12→12
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)] = 0.052Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.150H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.0864P)2 + 1.1188P]
where P = (Fo2 + 2Fc2)/3
2663 reflections(Δ/σ)max = 0.001
206 parametersΔρmax = 1.34 e Å−3
30 restraintsΔρmin = −1.40 e Å−3
Crystal data top
[Co2(C8H10O4)2(C14H14N4)]γ = 105.413 (5)°
Mr = 696.48V = 762.95 (8) Å3
Triclinic, P1Z = 1
a = 8.5415 (6) ÅMo Kα radiation
b = 8.8051 (5) ŵ = 1.14 mm−1
c = 10.8007 (5) ÅT = 293 K
α = 93.824 (4)°0.24 × 0.22 × 0.21 mm
β = 100.940 (4)°
Data collection top
Bruker APEX
diffractometer		2212 reflections with I > 2σ(I)
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		Rint = 0.030
Tmin = 0.756, Tmax = 0.788θmax = 25.0°
6296 measured reflectionsStandard reflections: 0
2663 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.052H-atom parameters constrained
wR(F2) = 0.150Δρmax = 1.34 e Å−3
S = 1.06Δρmin = −1.40 e Å−3
2663 reflectionsAbsolute structure: ?
206 parametersFlack parameter: ?
30 restraintsRogers parameter: ?
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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)
Co1.02761 (7)0.46504 (6)0.62430 (5)0.0287 (2)
O10.9612 (4)0.6678 (4)0.6589 (3)0.0424 (8)
O20.9184 (4)0.7201 (4)0.4586 (3)0.0416 (8)
O30.2725 (4)0.5894 (4)0.6746 (3)0.0469 (8)
O40.2232 (4)0.6331 (4)0.4730 (3)0.0471 (8)
N10.9757 (6)0.3705 (5)0.7847 (4)0.0516 (8)
C10.9135 (5)0.7472 (5)0.5736 (4)0.0320 (9)
C20.8510 (5)0.8860 (5)0.6110 (4)0.0336 (10)
H20.94670.98100.62990.040*
C30.7803 (6)0.8675 (6)0.7305 (4)0.0432 (11)
H3A0.86030.84300.79690.052*
H3B0.76350.96740.75970.052*
C40.6161 (5)0.7374 (6)0.7083 (4)0.0370 (10)
H4A0.63360.63570.68520.044*
H4B0.57460.73200.78590.044*
C50.4889 (5)0.7709 (5)0.6026 (4)0.0268 (8)
H50.47770.87520.62960.032*
C60.5562 (5)0.7871 (5)0.4806 (4)0.0337 (10)
H6A0.57100.68660.45070.040*
H6B0.47610.81310.41520.040*
C70.7222 (6)0.9163 (5)0.5037 (5)0.0382 (10)
H7A0.76430.92020.42630.046*
H7B0.70491.01850.52520.046*
C80.3170 (5)0.6554 (5)0.5811 (4)0.0337 (10)
C91.0536 (7)0.2819 (7)0.8583 (6)0.0653 (17)
H91.14460.24840.84610.078*
C100.9687 (11)0.2518 (9)0.9557 (6)0.104 (3)
H100.99350.19301.02130.125*
C110.8543 (7)0.3871 (6)0.8375 (5)0.0512 (13)
H110.77950.44180.80480.061*
N20.8493 (6)0.3188 (5)0.9406 (4)0.0516 (8)
C120.7737 (19)0.2877 (17)1.0436 (13)0.055 (3)0.488 (9)
H12A0.71960.36901.05840.066*0.488 (9)
H12B0.85910.29451.11880.066*0.488 (9)
C130.6462 (19)0.1259 (17)1.0251 (14)0.047 (3)0.488 (9)
C140.653 (3)0.034 (3)1.120 (2)0.064 (5)0.488 (9)
H140.73790.03931.18930.077*0.488 (9)
C150.516 (3)0.076 (3)0.9209 (18)0.062 (4)0.488 (9)
H150.54340.13020.85360.074*0.488 (9)
C12'0.6974 (18)0.3329 (16)1.0078 (12)0.055 (3)0.512 (9)
H12C0.74100.37831.09600.066*0.512 (9)
H12D0.63910.40170.96480.066*0.512 (9)
C13'0.5796 (18)0.1695 (16)1.0001 (13)0.047 (3)0.512 (9)
C14'0.598 (3)0.076 (3)1.093 (2)0.064 (5)0.512 (9)
H14'0.65960.13671.16950.077*0.512 (9)
C15'0.456 (2)0.110 (3)0.8901 (17)0.062 (4)0.512 (9)
H15'0.41580.16370.82540.074*0.512 (9)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co0.0260 (3)0.0332 (3)0.0288 (3)0.0076 (2)0.0100 (2)0.0080 (2)
O10.0416 (19)0.0388 (17)0.0489 (18)0.0177 (15)0.0047 (15)0.0077 (15)
O20.045 (2)0.0374 (17)0.0500 (19)0.0156 (15)0.0224 (15)0.0082 (14)
O30.0319 (18)0.052 (2)0.054 (2)−0.0014 (15)0.0210 (15)0.0051 (16)
O40.0237 (17)0.051 (2)0.056 (2)0.0035 (15)−0.0051 (15)0.0008 (16)
N10.056 (2)0.0509 (18)0.0342 (15)−0.0122 (15)0.0144 (14)0.0067 (13)
C10.017 (2)0.027 (2)0.049 (3)0.0003 (16)0.0098 (18)0.0050 (19)
C20.019 (2)0.027 (2)0.052 (3)0.0010 (16)0.0096 (18)0.0020 (19)
C30.026 (2)0.058 (3)0.040 (2)0.011 (2)−0.0007 (19)−0.010 (2)
C40.027 (2)0.054 (3)0.034 (2)0.014 (2)0.0094 (18)0.015 (2)
C50.018 (2)0.029 (2)0.035 (2)0.0073 (16)0.0076 (16)0.0060 (17)
C60.026 (2)0.043 (2)0.034 (2)0.0116 (19)0.0066 (17)0.0079 (18)
C70.032 (2)0.037 (2)0.055 (3)0.016 (2)0.021 (2)0.019 (2)
C80.026 (2)0.031 (2)0.047 (3)0.0101 (18)0.013 (2)0.0025 (19)
C90.051 (3)0.057 (3)0.074 (4)0.004 (3)−0.012 (3)0.035 (3)
C100.128 (7)0.085 (5)0.041 (3)−0.046 (5)−0.023 (4)0.047 (3)
C110.052 (3)0.051 (3)0.048 (3)−0.005 (2)0.031 (2)0.005 (2)
N20.056 (2)0.0509 (18)0.0342 (15)−0.0122 (15)0.0144 (14)0.0067 (13)
C120.064 (9)0.051 (6)0.041 (6)−0.012 (5)0.034 (6)−0.005 (4)
C130.056 (9)0.040 (6)0.044 (5)−0.007 (4)0.038 (6)−0.006 (4)
C140.060 (13)0.074 (12)0.043 (8)−0.014 (7)0.021 (8)−0.005 (7)
C150.071 (12)0.067 (9)0.040 (8)−0.002 (7)0.022 (7)0.011 (5)
C12'0.064 (9)0.051 (6)0.041 (6)−0.012 (5)0.034 (6)−0.005 (4)
C13'0.056 (9)0.040 (6)0.044 (5)−0.007 (4)0.038 (6)−0.006 (4)
C14'0.060 (13)0.074 (12)0.043 (8)−0.014 (7)0.021 (8)−0.005 (7)
C15'0.071 (12)0.067 (9)0.040 (8)−0.002 (7)0.022 (7)0.011 (5)
Geometric parameters (Å, °) top
Co—O2i2.008 (3)C6—H6B0.9700
Co—O3ii2.035 (3)C7—H7A0.9700
Co—O12.044 (3)C7—H7B0.9700
Co—N12.044 (4)C9—C101.388 (10)
Co—O4iii2.117 (3)C9—H90.9300
Co—Coi2.7758 (10)C10—N21.298 (11)
O1—C11.265 (5)C10—H100.9300
O2—C11.260 (5)C11—N21.303 (7)
O2—Coi2.008 (3)C11—H110.9300
O3—C81.268 (6)N2—C121.395 (13)
O3—Coiv2.035 (3)N2—C12'1.630 (14)
O4—C81.255 (5)C12—C131.52 (2)
O4—Coiii2.117 (3)C12—H12A0.9700
N1—C111.310 (7)C12—H12B0.9700
N1—C91.356 (7)C13—C141.34 (3)
C1—C21.518 (6)C13—C151.38 (2)
C2—C31.526 (6)C14—C15v1.47 (4)
C2—C71.528 (6)C14—H140.9300
C2—H20.9800C15—C14v1.47 (4)
C3—C41.522 (6)C15—H150.9300
C3—H3A0.9700C12'—C13'1.507 (19)
C3—H3B0.9700C12'—H12C0.9700
C4—C51.521 (5)C12'—H12D0.9700
C4—H4A0.9700C13'—C14'1.35 (3)
C4—H4B0.9700C13'—C15'1.40 (2)
C5—C81.513 (6)C14'—C15'v1.62 (3)
C5—C61.535 (6)C14'—H14'0.9300
C5—H50.9800C15'—C14'v1.62 (3)
C6—C71.529 (6)C15'—H15'0.9300
C6—H6A0.9700
O2i—Co—O3ii91.45 (14)C2—C7—C6111.7 (3)
O2i—Co—O1164.36 (13)C2—C7—H7A109.3
O3ii—Co—O190.51 (14)C6—C7—H7A109.3
O2i—Co—N198.07 (16)C2—C7—H7B109.3
O3ii—Co—N1104.53 (16)C6—C7—H7B109.3
O1—Co—N196.44 (16)H7A—C7—H7B107.9
O2i—Co—O4iii88.63 (14)O4—C8—O3123.1 (4)
O3ii—Co—O4iii164.38 (14)O4—C8—C5118.6 (4)
O1—Co—O4iii85.35 (13)O3—C8—C5118.3 (4)
N1—Co—O4iii90.91 (16)N1—C9—C10105.5 (7)
O2i—Co—Coi81.73 (9)N1—C9—H9127.3
O3ii—Co—Coi97.00 (10)C10—C9—H9127.3
O1—Co—Coi82.63 (9)N2—C10—C9109.2 (5)
N1—Co—Coi158.46 (13)N2—C10—H10125.4
O4iii—Co—Coi67.55 (10)C9—C10—H10125.4
C1—O1—Co124.3 (3)N2—C11—N1112.8 (6)
C1—O2—Coi127.3 (3)N2—C11—H11123.6
C8—O3—Coiv109.5 (3)N1—C11—H11123.6
C8—O4—Coiii142.2 (3)C10—N2—C11106.6 (5)
C11—N1—C9105.9 (5)C10—N2—C12105.7 (9)
C11—N1—Co124.5 (4)C11—N2—C12147.6 (9)
C9—N1—Co129.6 (4)C10—N2—C12'138.7 (7)
O2—C1—O1123.6 (4)C11—N2—C12'114.6 (7)
O2—C1—C2117.6 (4)C12—N2—C12'33.2 (7)
O1—C1—C2118.8 (4)N2—C12—C13113.8 (10)
C1—C2—C3112.7 (4)N2—C12—H12A108.8
C1—C2—C7112.7 (4)C13—C12—H12A108.8
C3—C2—C7109.5 (4)N2—C12—H12B108.8
C1—C2—H2107.2C13—C12—H12B108.8
C3—C2—H2107.2H12A—C12—H12B107.7
C7—C2—H2107.2C14—C13—C15118.9 (18)
C4—C3—C2112.5 (4)C14—C13—C12118.3 (16)
C4—C3—H3A109.1C15—C13—C12122.6 (15)
C2—C3—H3A109.1C13—C14—C15v98.2 (16)
C4—C3—H3B109.1C13—C14—H14130.9
C2—C3—H3B109.1C15v—C14—H14130.9
H3A—C3—H3B107.8C13—C15—C14v141.3 (19)
C5—C4—C3110.3 (4)C13—C15—H15109.3
C5—C4—H4A109.6C14v—C15—H15109.3
C3—C4—H4A109.6C13'—C12'—N2108.8 (9)
C5—C4—H4B109.6C13'—C12'—H12C109.9
C3—C4—H4B109.6N2—C12'—H12C109.9
H4A—C4—H4B108.1C13'—C12'—H12D109.9
C8—C5—C4114.2 (3)N2—C12'—H12D109.9
C8—C5—C6112.8 (3)H12C—C12'—H12D108.3
C4—C5—C6110.2 (3)C14'—C13'—C15'119.8 (17)
C8—C5—H5106.3C14'—C13'—C12'121.5 (15)
C4—C5—H5106.3C15'—C13'—C12'118.6 (13)
C6—C5—H5106.3C13'—C14'—C15'v138.1 (19)
C7—C6—C5111.1 (3)C13'—C14'—H14'111.0
C7—C6—H6A109.4C15'v—C14'—H14'111.0
C5—C6—H6A109.4C13'—C15'—C14'v100.5 (13)
C7—C6—H6B109.4C13'—C15'—H15'129.7
C5—C6—H6B109.4C14'v—C15'—H15'129.7
H6A—C6—H6B108.0
O2i—Co—O1—C13.5 (7)Coiv—O3—C8—O4−5.3 (5)
O3ii—Co—O1—C1100.7 (3)Coiv—O3—C8—C5172.4 (3)
N1—Co—O1—C1−154.6 (3)C4—C5—C8—O4−153.7 (4)
O4iii—Co—O1—C1−64.2 (3)C6—C5—C8—O4−26.8 (5)
Coi—Co—O1—C13.7 (3)C4—C5—C8—O328.5 (5)
O2i—Co—N1—C11−139.8 (4)C6—C5—C8—O3155.4 (4)
O3ii—Co—N1—C11126.6 (4)C11—N1—C9—C10−0.6 (6)
O1—Co—N1—C1134.4 (4)Co—N1—C9—C10179.1 (4)
O4iii—Co—N1—C11−51.1 (4)N1—C9—C10—N2−0.2 (7)
Coi—Co—N1—C11−51.9 (6)C9—N1—C11—N21.2 (6)
O2i—Co—N1—C940.6 (5)Co—N1—C11—N2−178.5 (3)
O3ii—Co—N1—C9−53.1 (5)C9—C10—N2—C110.9 (7)
O1—Co—N1—C9−145.3 (5)C9—C10—N2—C12−178.2 (7)
O4iii—Co—N1—C9129.3 (5)C9—C10—N2—C12'177.2 (8)
Coi—Co—N1—C9128.5 (5)N1—C11—N2—C10−1.3 (6)
Coi—O2—C1—O18.4 (6)N1—C11—N2—C12177.0 (12)
Coi—O2—C1—C2−173.4 (3)N1—C11—N2—C12'−178.7 (6)
Co—O1—C1—O2−8.0 (6)C10—N2—C12—C13−83.2 (12)
Co—O1—C1—C2173.8 (3)C11—N2—C12—C1398.5 (15)
O2—C1—C2—C3155.3 (4)C12'—N2—C12—C1391.3 (19)
O1—C1—C2—C3−26.4 (5)N2—C12—C13—C14132.3 (16)
O2—C1—C2—C730.8 (5)N2—C12—C13—C15−54 (2)
O1—C1—C2—C7−150.9 (4)C15—C13—C14—C15v−12 (3)
C1—C2—C3—C4−70.3 (5)C12—C13—C14—C15v162.6 (15)
C7—C2—C3—C456.0 (5)C14—C13—C15—C14v18 (4)
C2—C3—C4—C5−57.7 (5)C12—C13—C15—C14v−155 (3)
C3—C4—C5—C8−175.0 (3)C10—N2—C12'—C13'−62.0 (14)
C3—C4—C5—C656.8 (5)C11—N2—C12'—C13'114.1 (10)
C8—C5—C6—C7174.5 (3)C12—N2—C12'—C13'−70.1 (16)
C4—C5—C6—C7−56.6 (5)N2—C12'—C13'—C14'90.6 (17)
C1—C2—C7—C671.5 (5)N2—C12'—C13'—C15'−85.0 (15)
C3—C2—C7—C6−54.8 (5)C15'—C13'—C14'—C15'v18 (4)
C5—C6—C7—C256.1 (5)C12'—C13'—C14'—C15'v−158 (2)
Coiii—O4—C8—O312.1 (8)C14'—C13'—C15'—C14'v−12 (3)
Coiii—O4—C8—C5−165.6 (3)C12'—C13'—C15'—C14'v163.8 (13)
Symmetry codes: (i) −x+2, −y+1, −z+1; (ii) x+1, y, z; (iii) −x+1, −y+1, −z+1; (iv) x−1, y, z; (v) −x+1, −y, −z+2.
Acknowledgements top

We thank Zhejiang Ocean University and the China–Japan Union Hospital of Jilin University for support.

references
References top

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Li, B.-B., Fang, G.-X., Ji, X.-N., Xiao, B. & Tiekink, E. R. T. (2009). Acta Cryst. E65, m1012.

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Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.

Yang, J., Ma, J.-F., Batten, S. R. & Su, Z.-M. (2008). Chem. Commun. pp. 2233–2235.