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Acta Cryst. (2009). E65, m782    [ doi:10.1107/S1600536809021801 ]

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

N. Wang, Y.-J. Wang and Q.-Y. Lin

Abstract top

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...[pi] interactions.

Comment top

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).

Related literature top

7-Oxabicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride (norcantharidin) is a lower toxicity anticancer drug, see: Shimi et al. (1982). For cobalt complexes of norcantharidin, see: Wang et al. (1988) and of imidazole, see: Furenlid et al. (1986); Zhu et al. (2003). Cg5 is the centroid of the N3/N4/C9–C11 ring.

Experimental top

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 top

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)].

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); 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: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of the molecule of (I) showing the atom-labelling scheme with displacement ellipsoids drawn at the 30% probability.
Poly[bis(1H-imidazole)(µ3-7-oxabicyclo[2.2.1]heptane-2,3- dicarboxylato)cadmium(II)] top
Crystal data top
[Cd(C8H8O5)(C3H4N2)2]F(000) = 864
Mr = 432.71Dx = 1.817 Mg m−3
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 mm−1
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 top
Bruker APEXII area-detector
diffractometer		2777 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 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)] = 0.075Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.216H-atom parameters constrained
S = 1.05 w = 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 Å−3
234 restraintsΔρmin = −1.26 e Å−3
Crystal data top
[Cd(C8H8O5)(C3H4N2)2]V = 1581.7 (3) Å3
Mr = 432.71Z = 4
Monoclinic, P21/cMo Kα radiation
a = 12.5374 (16) ŵ = 1.41 mm−1
b = 9.6596 (13) ÅT = 296 K
c = 14.1635 (17) Å0.12 × 0.06 × 0.05 mm
β = 112.761 (7)°
Data collection top
Bruker APEXII area-detector
diffractometer		2777 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		2310 reflections with I > 2σ(I)
Tmin = 0.900, Tmax = 0.932Rint = 0.035
10791 measured reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.075 w = 1/[σ2(Fo2) + (0.1141P)2 + 20.9278P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.216Δρmax = 2.92 e Å−3
S = 1.05Δρmin = −1.26 e Å−3
2777 reflectionsAbsolute structure: ?
217 parametersFlack parameter: ?
234 restraintsRogers parameter: ?
H-atom parameters constrained
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
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) top
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, °) top
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, °) top
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.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O5i0.862.092.830 (12)144
N4—H4B···O1ii0.862.443.012 (17)125
N4—H4B···O2ii0.862.052.818 (13)149
C6—H6A···O40.982.562.92 (2)101
C11—H11A···O50.932.343.239 (15)164
C14—H14A···O2iii0.932.553.358 (15)145
C12—H12A···Cg5iv0.932.763.565 (14)145
Symmetry codes: (i) x, y+1, z; (ii) −x+1, y−1/2, −z+1/2; (iii) −x+1, y+1/2, −z+1/2; (iv) −x+1, −y, −z+1.
Acknowledgements top

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

references
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