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Acta Crystallogr Sect E Struct Rep Online. 2009 July 1; 65(Pt 7): m782.
Published online 2009 June 17. doi:  10.1107/S1600536809021801
PMCID: PMC2969310

Poly[bis­(1H-imidazole)(μ3-7-oxabicyclo­[2.2.1]heptane-2,3-dicarboxyl­ato)cadmium(II)]

Abstract

The title compound, [Cd(C8H8O5)(C3H4N2)2]n, was synthesized by the reaction of 7-oxabicyclo­[2.2.1]heptane-2,3-dicarboxylic anhydride, cadmium acetate and imidazole. The CdII atom is seven-coordinated in a distorted penta­gonal-bipyramidal configuration by five O atoms from carboxyl­ate groups of three 7-oxabicyclo­[2.2.1]heptane-2,3-dicarboxylate ligands and two N atoms from two imidazole ligands. The crystal structure is stabilized by N—H(...)O and C—H(...)O hydrogen-bonding and C—H(...)π inter­actions.

Related literature

7-Oxabicyclo­[2.2.1]heptane-2,3-dicarboxylic anhydride (nor­cantharidin) is a lower toxicity anti­cancer drug, see: Shimi et al. (1982 [triangle]). For cobalt complexes of norcantharidin, see: Wang et al. (1988 [triangle]) and of imidazole, see: Furenlid et al. (1986 [triangle]); Zhu et al. (2003 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-0m782-scheme1.jpg

Experimental

Crystal data

  • [Cd(C8H8O5)(C3H4N2)2]
  • M r = 432.71
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-0m782-efi1.jpg
  • a = 12.5374 (16) Å
  • b = 9.6596 (13) Å
  • c = 14.1635 (17) Å
  • β = 112.761 (7)°
  • V = 1581.7 (3) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 1.41 mm−1
  • T = 296 K
  • 0.12 × 0.06 × 0.05 mm

Data collection

  • Bruker APEXII area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.900, T max = 0.932
  • 10791 measured reflections
  • 2777 independent reflections
  • 2310 reflections with I > 2σ(I)
  • R int = 0.035

Refinement

  • R[F 2 > 2σ(F 2)] = 0.075
  • wR(F 2) = 0.216
  • S = 1.05
  • 2777 reflections
  • 217 parameters
  • 234 restraints
  • H-atom parameters constrained
  • Δρmax = 2.92 e Å−3
  • Δρmin = −1.26 e Å−3

Data collection: APEX2 (Bruker, 2006 [triangle]); cell refinement: SAINT (Bruker, 2006 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809021801/at2804sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809021801/at2804Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors thank the Natural Science Foundation of Zhejiang Province, China (grant No. Y407301) for financial support.

supplementary crystallographic information

Comment

7-Oxabicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride (norcantharidin) derived from cantharidin is a lower toxicity anticancer drug (Shimi et al., 1982). Imidazole is reputed as biocatalyst and biological ligand. Several cobalt complexes of norcantharidin (Wang et al., 1988) and of imidazole (Furenlid et al., 1986; Zhu et al., 2003) have been reported.

In the title compound, (I), (Fig. 1), the cadmium atom is seven-coordinated in a distorted pentagonal bipyramidal configuration, defined by five oxygen atoms (O2, O3, O3A, O4B, O5B) from carboxylate groups of three 7-oxabicyclo[2.2.1]heptane-2,3-dicarboxylic anhydrides and two nitrogen atoms (N1, N3) from two imidazoles. Each 7-oxabicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride acts as a four-coordinared bridging linker that connects two cadmium centers.

The crystal structure is stabilized by N—H···O, C—H···O hydrogen bonding and C—H···π interactions (Table 1).

Experimental

7-Oxabicyclo[2.2.1] heptane-2,3-dicarboxylic anhydride, cadmium acetate and imidazole were dissolved in 15 mL distilled water. The mixture was sealed in a 25 mL Teflon-lined stainless vessel and heated at 443 K for 3 d, then cooled slowly to room temperature. A crystal suitable for X-ray diffraction was obtained.

Refinement

The H atoms bonded to C and N atoms were positioned geometrically and refined using a riding model [aromatic C—H 0.93 Å, aliphatic C—H = 0.97 (2) Å and N—H = 0.86 Å, Uiso(H) = 1.2Ueq(C)].

Figures

Fig. 1.
A view of the molecule of (I) showing the atom-labelling scheme with displacement ellipsoids drawn at the 30% probability.

Crystal data

[Cd(C8H8O5)(C3H4N2)2]F(000) = 864
Mr = 432.71Dx = 1.817 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3164 reflections
a = 12.5374 (16) Åθ = 1.8–25.0°
b = 9.6596 (13) ŵ = 1.41 mm1
c = 14.1635 (17) ÅT = 296 K
β = 112.761 (7)°Block, colourless
V = 1581.7 (3) Å30.12 × 0.06 × 0.05 mm
Z = 4

Data collection

Bruker APEXII area-detector diffractometer2777 independent reflections
Radiation source: fine-focus sealed tube2310 reflections with I > 2σ(I)
graphiteRint = 0.035
ω scansθmax = 25.0°, θmin = 1.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −14→13
Tmin = 0.900, Tmax = 0.932k = −9→11
10791 measured reflectionsl = −16→16

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.075Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.216H-atom parameters constrained
S = 1.05w = 1/[σ2(Fo2) + (0.1141P)2 + 20.9278P] where P = (Fo2 + 2Fc2)/3
2777 reflections(Δ/σ)max < 0.001
217 parametersΔρmax = 2.92 e Å3
234 restraintsΔρmin = −1.26 e Å3

Special details

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)

xyzUiso*/Ueq
Cd10.56124 (6)0.12069 (7)0.41461 (5)0.0343 (3)
C10.3497 (10)−0.0468 (14)0.3258 (10)0.054 (2)
C20.2845 (10)−0.2300 (14)0.1484 (11)0.057 (2)
C30.2272 (12)−0.0995 (16)0.2847 (13)0.072 (2)
H3A0.2224−0.16100.33800.086*
C40.1928 (11)−0.1894 (18)0.1877 (12)0.073 (2)
H4A0.1672−0.27720.20660.088*
C50.1415 (13)−0.0051 (18)0.2677 (13)0.083 (3)
H5A0.16170.07620.31260.099*
C60.0917 (13)−0.1236 (17)0.1263 (14)0.080 (3)
H6A0.0743−0.13630.05320.096*
C70.0267 (13)−0.0946 (18)0.2649 (14)0.083 (3)
H7A0.0478−0.16470.31800.100*
H7B−0.0321−0.03460.27150.100*
C8−0.0141 (13)−0.1606 (19)0.1553 (13)0.081 (3)
H8A−0.0851−0.11870.10840.097*
H8B−0.0246−0.25990.15730.097*
C90.7916 (10)−0.0684 (14)0.4431 (9)0.054 (3)
H9A0.8443−0.00220.48150.064*
C100.8193 (11)−0.1875 (15)0.4113 (10)0.060 (3)
H10A0.8935−0.21870.42310.072*
C110.6339 (10)−0.1723 (13)0.3608 (9)0.051 (2)
H11A0.5560−0.19530.32990.061*
C120.3507 (10)0.3209 (13)0.4170 (9)0.050 (2)
H12A0.31390.25180.43880.060*
C130.3119 (11)0.4481 (13)0.3898 (10)0.055 (3)
H13A0.24320.48450.38970.066*
C140.4742 (10)0.4295 (13)0.3745 (9)0.050 (2)
H14A0.53960.45090.36160.060*
N10.4556 (8)0.3092 (9)0.4073 (6)0.0389 (19)
N20.3900 (9)0.5160 (10)0.3620 (8)0.055 (3)
H2A0.38490.59990.34040.066*
N30.6737 (7)−0.0577 (9)0.4109 (6)0.0385 (19)
N40.7219 (10)−0.2529 (10)0.3601 (8)0.058 (3)
H4B0.7153−0.33260.33130.070*
O10.1232 (10)0.0205 (13)0.1600 (10)0.102 (3)
O20.3853 (6)0.0273 (8)0.2739 (6)0.0493 (16)
O30.4150 (8)−0.0683 (11)0.4176 (6)0.064 (2)
O40.2664 (7)−0.2321 (9)0.0572 (7)0.0558 (18)
O50.3769 (6)−0.2772 (8)0.2164 (5)0.0425 (15)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Cd10.0361 (5)0.0323 (5)0.0371 (5)0.0007 (3)0.0170 (3)0.0026 (3)
C10.042 (4)0.063 (4)0.067 (4)−0.001 (3)0.032 (3)−0.023 (4)
C20.039 (4)0.064 (5)0.076 (5)−0.007 (4)0.032 (4)−0.028 (4)
C30.049 (4)0.082 (5)0.089 (5)−0.006 (4)0.031 (4)−0.034 (4)
C40.048 (4)0.083 (5)0.091 (5)−0.003 (4)0.029 (4)−0.035 (4)
C50.059 (4)0.087 (5)0.095 (5)−0.004 (4)0.023 (4)−0.029 (4)
C60.054 (4)0.085 (5)0.094 (5)−0.004 (4)0.021 (4)−0.030 (4)
C70.055 (5)0.097 (5)0.097 (5)−0.004 (4)0.029 (4)−0.030 (5)
C80.055 (4)0.091 (5)0.096 (5)−0.003 (4)0.028 (4)−0.032 (5)
C90.041 (5)0.056 (6)0.060 (5)0.011 (5)0.014 (4)0.002 (5)
C100.047 (5)0.064 (6)0.067 (6)0.016 (5)0.018 (5)0.001 (5)
C110.043 (4)0.052 (5)0.057 (5)0.006 (4)0.020 (4)−0.001 (4)
C120.044 (5)0.053 (5)0.064 (5)0.003 (4)0.033 (4)0.000 (4)
C130.051 (5)0.052 (5)0.068 (6)0.007 (5)0.029 (5)0.003 (5)
C140.050 (5)0.050 (5)0.057 (5)−0.002 (5)0.029 (4)0.001 (5)
N10.049 (5)0.030 (4)0.041 (4)−0.001 (4)0.021 (4)−0.003 (4)
N20.071 (7)0.032 (5)0.065 (6)0.014 (5)0.031 (5)0.013 (4)
N30.037 (5)0.037 (5)0.041 (5)0.003 (4)0.015 (4)0.001 (4)
N40.087 (8)0.038 (5)0.054 (6)0.017 (5)0.031 (5)−0.007 (4)
O10.081 (5)0.090 (6)0.109 (6)0.012 (5)0.006 (5)0.000 (5)
O20.046 (3)0.050 (4)0.060 (4)0.001 (3)0.029 (3)0.006 (3)
O30.066 (5)0.086 (5)0.046 (4)0.018 (4)0.028 (3)0.004 (4)
O40.050 (4)0.055 (4)0.060 (4)0.011 (3)0.019 (3)−0.002 (3)
O50.045 (3)0.042 (4)0.046 (3)0.003 (3)0.024 (3)−0.005 (3)

Geometric parameters (Å, °)

Cd1—N12.230 (9)C7—H7A0.9700
Cd1—N32.240 (9)C7—H7B0.9700
Cd1—O3i2.333 (8)C8—H8A0.9700
Cd1—O5ii2.476 (7)C8—H8B0.9700
Cd1—O4ii2.487 (8)C9—C101.329 (18)
Cd1—O22.500 (8)C9—N31.372 (14)
Cd1—O32.599 (10)C9—H9A0.9300
C1—O21.226 (15)C10—N41.316 (17)
C1—O31.258 (15)C10—H10A0.9300
C1—C31.506 (17)C11—N31.305 (15)
C2—O41.222 (15)C11—N41.354 (15)
C2—O51.271 (15)C11—H11A0.9300
C2—C41.510 (17)C12—C131.323 (18)
C3—C51.36 (2)C12—N11.379 (14)
C3—C41.540 (19)C12—H12A0.9300
C3—H3A0.9800C13—N21.357 (16)
C4—C61.38 (2)C13—H13A0.9300
C4—H4A0.9800C14—N11.306 (15)
C5—O11.47 (2)C14—N21.304 (15)
C5—C71.67 (2)C14—H14A0.9300
C5—H5A0.9800N2—H2A0.8600
C6—O11.476 (18)N4—H4B0.8600
C6—C81.57 (2)O3—Cd1i2.333 (8)
C6—H6A0.9800O4—Cd1iii2.487 (8)
C7—C81.57 (2)O5—Cd1iii2.476 (7)
N1—Cd1—N3174.2 (3)C8—C6—H6A112.5
N1—Cd1—O3i93.7 (3)C8—C7—C5100.5 (13)
N3—Cd1—O3i91.4 (3)C8—C7—H7A111.7
N1—Cd1—O5ii89.6 (3)C5—C7—H7A111.7
N3—Cd1—O5ii84.6 (3)C8—C7—H7B111.7
O3i—Cd1—O5ii153.7 (3)C5—C7—H7B111.7
N1—Cd1—O4ii90.2 (3)H7A—C7—H7B109.4
N3—Cd1—O4ii85.8 (3)C7—C8—C6100.4 (12)
O3i—Cd1—O4ii101.5 (3)C7—C8—H8A111.7
O5ii—Cd1—O4ii52.3 (3)C6—C8—H8A111.7
N1—Cd1—O286.1 (3)C7—C8—H8B111.7
N3—Cd1—O294.2 (3)C6—C8—H8B111.7
O3i—Cd1—O2117.3 (3)H8A—C8—H8B109.5
O5ii—Cd1—O289.0 (2)C10—C9—N3110.0 (12)
O4ii—Cd1—O2141.1 (3)C10—C9—H9A125.0
N1—Cd1—O399.5 (3)N3—C9—H9A125.0
N3—Cd1—O385.1 (3)N4—C10—C9107.1 (11)
O3i—Cd1—O369.1 (4)N4—C10—H10A126.5
O5ii—Cd1—O3136.0 (3)C9—C10—H10A126.5
O4ii—Cd1—O3166.8 (3)N3—C11—N4110.6 (11)
O2—Cd1—O349.4 (3)N3—C11—H11A124.7
O2—C1—O3118.3 (11)N4—C11—H11A124.7
O2—C1—C3121.3 (13)C13—C12—N1107.8 (11)
O3—C1—C3120.1 (13)C13—C12—H12A126.1
O4—C2—O5122.5 (10)N1—C12—H12A126.1
O4—C2—C4122.5 (13)C12—C13—N2107.9 (11)
O5—C2—C4114.5 (12)C12—C13—H13A126.1
C5—C3—C1117.4 (13)N2—C13—H13A126.1
C5—C3—C4106.9 (13)N1—C14—N2111.8 (10)
C1—C3—C4115.3 (11)N1—C14—H14A124.1
C5—C3—H3A105.4N2—C14—H14A124.1
C1—C3—H3A105.4C14—N1—C12105.7 (10)
C4—C3—H3A105.4C14—N1—Cd1124.0 (7)
C6—C4—C2122.0 (16)C12—N1—Cd1129.4 (8)
C6—C4—C3100.0 (12)C14—N2—C13106.8 (10)
C2—C4—C3119.0 (11)C14—N2—H2A126.6
C6—C4—H4A104.6C13—N2—H2A126.6
C2—C4—H4A104.6C11—N3—C9104.6 (10)
C3—C4—H4A104.6C11—N3—Cd1123.6 (7)
C3—C5—O195.3 (13)C9—N3—Cd1131.1 (8)
C3—C5—C7105.8 (14)C10—N4—C11107.7 (10)
O1—C5—C7106.0 (12)C10—N4—H4B126.1
C3—C5—H5A115.8C11—N4—H4B126.1
O1—C5—H5A115.8C6—O1—C595.3 (13)
C7—C5—H5A115.8C1—O2—Cd198.4 (7)
C4—C6—O199.4 (12)C1—O3—Cd1i149.9 (8)
C4—C6—C8113.0 (16)C1—O3—Cd192.7 (8)
O1—C6—C8106.1 (13)Cd1i—O3—Cd1110.9 (4)
C4—C6—H6A112.5C2—O4—Cd1iii92.6 (7)
O1—C6—H6A112.5C2—O5—Cd1iii91.9 (6)
O2—C1—C3—C5−67.4 (19)C10—C9—N3—Cd1−170.3 (9)
O3—C1—C3—C5106.4 (18)N1—Cd1—N3—C11−105 (3)
O2—C1—C3—C460.1 (19)O3i—Cd1—N3—C11105.9 (9)
O3—C1—C3—C4−126.2 (15)O5ii—Cd1—N3—C11−100.2 (9)
O4—C2—C4—C6−15 (2)O4ii—Cd1—N3—C11−152.6 (9)
O5—C2—C4—C6173.5 (13)O2—Cd1—N3—C11−11.6 (9)
O4—C2—C4—C3−140.1 (15)O3—Cd1—N3—C1137.0 (9)
O5—C2—C4—C348 (2)N1—Cd1—N3—C964 (3)
C5—C3—C4—C63.3 (19)O3i—Cd1—N3—C9−84.9 (10)
C1—C3—C4—C6−129.2 (15)O5ii—Cd1—N3—C969.0 (10)
C5—C3—C4—C2138.9 (16)O4ii—Cd1—N3—C916.6 (10)
C1—C3—C4—C26(2)O2—Cd1—N3—C9157.6 (10)
C1—C3—C5—O191.7 (15)O3—Cd1—N3—C9−153.8 (10)
C4—C3—C5—O1−39.6 (16)C9—C10—N4—C110.0 (15)
C1—C3—C5—C7−160.0 (14)N3—C11—N4—C100.2 (14)
C4—C3—C5—C768.7 (17)C4—C6—O1—C5−60.7 (15)
C2—C4—C6—O1−99.0 (17)C8—C6—O1—C556.7 (14)
C3—C4—C6—O134.8 (16)C3—C5—O1—C660.4 (13)
C2—C4—C6—C8149.0 (14)C7—C5—O1—C6−47.8 (13)
C3—C4—C6—C8−77.2 (16)O3—C1—O2—Cd1−11.1 (12)
C3—C5—C7—C8−76.9 (17)C3—C1—O2—Cd1162.8 (10)
O1—C5—C7—C823.5 (16)N1—Cd1—O2—C1−99.8 (7)
C5—C7—C8—C610.1 (16)N3—Cd1—O2—C186.1 (7)
C4—C6—C8—C765.5 (17)O3i—Cd1—O2—C1−7.6 (8)
O1—C6—C8—C7−42.4 (17)O5ii—Cd1—O2—C1170.6 (7)
N3—C9—C10—N4−0.3 (15)O4ii—Cd1—O2—C1174.6 (7)
N1—C12—C13—N20.7 (14)O3—Cd1—O2—C16.2 (7)
N2—C14—N1—C12−0.4 (13)O2—C1—O3—Cd1i153.0 (13)
N2—C14—N1—Cd1169.4 (8)C3—C1—O3—Cd1i−21 (2)
C13—C12—N1—C14−0.2 (13)O2—C1—O3—Cd110.5 (11)
C13—C12—N1—Cd1−169.3 (8)C3—C1—O3—Cd1−163.4 (10)
N3—Cd1—N1—C14−18 (3)N1—Cd1—O3—C170.6 (7)
O3i—Cd1—N1—C14131.6 (9)N3—Cd1—O3—C1−105.8 (7)
O5ii—Cd1—N1—C14−22.2 (9)O3i—Cd1—O3—C1160.9 (9)
O4ii—Cd1—N1—C1430.1 (9)O5ii—Cd1—O3—C1−28.7 (8)
O2—Cd1—N1—C14−111.2 (9)O4ii—Cd1—O3—C1−152.6 (11)
O3—Cd1—N1—C14−158.9 (9)O2—Cd1—O3—C1−6.0 (6)
N3—Cd1—N1—C12150 (3)N1—Cd1—O3—Cd1i−90.3 (4)
O3i—Cd1—N1—C12−61.1 (10)N3—Cd1—O3—Cd1i93.3 (4)
O5ii—Cd1—N1—C12145.1 (9)O3i—Cd1—O3—Cd1i0.0
O4ii—Cd1—N1—C12−162.7 (9)O5ii—Cd1—O3—Cd1i170.4 (3)
O2—Cd1—N1—C1256.1 (9)O4ii—Cd1—O3—Cd1i46.5 (14)
O3—Cd1—N1—C128.4 (10)O2—Cd1—O3—Cd1i−166.9 (5)
N1—C14—N2—C130.8 (14)O5—C2—O4—Cd1iii9.0 (13)
C12—C13—N2—C14−0.9 (14)C4—C2—O4—Cd1iii−162.4 (13)
N4—C11—N3—C9−0.4 (13)O4—C2—O5—Cd1iii−9.0 (13)
N4—C11—N3—Cd1171.2 (7)C4—C2—O5—Cd1iii163.0 (11)
C10—C9—N3—C110.4 (14)

Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+1, y+1/2, −z+1/2; (iii) −x+1, y−1/2, −z+1/2.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N2—H2A···O5iv0.862.092.830 (12)144
N4—H4B···O1iii0.862.443.012 (17)125
N4—H4B···O2iii0.862.052.818 (13)149
C6—H6A···O40.982.562.92 (2)101
C11—H11A···O50.932.343.239 (15)164
C14—H14A···O2ii0.932.553.358 (15)145
C12—H12A···Cg5i0.932.763.565 (14)145

Symmetry codes: (iv) x, y+1, z; (iii) −x+1, y−1/2, −z+1/2; (ii) −x+1, y+1/2, −z+1/2; (i) −x+1, −y, −z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: AT2804).

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