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Acta Cryst. (2012). E68, m1364    [ doi:10.1107/S1600536812042444 ]

Poly[di-[mu]3-hydroxy[[mu]4-5-(4-carboxyphenyl)pyridine-2-carboxylato-[kappa]5N,O2:O2':O4:O4']dicadmium]

F.-J. Meng, H.-Q. Jia, N.-H. Hu and H. Zhou

Abstract top

The asymmetric unit of the title polymeric complex, [Cd2(C13H7NO4)(OH)2]n, consists of two independent CdII atoms, one 5-(4-carboxyphenyl)pyridine-2-carboxylate ligand and two hydroxy groups. One CdII atom is six-coordinated by two O atoms from two ligand molecules and by four [mu]3-OH groups in a distorted trigonal-prismatic geometry. The other is five-coordinated by one N and two O atoms from two ligands and by two [mu]3-OH groups, forming a distorted square-pyramidal geometry. The two independent CdII atoms are connected by the ligand molecules and the OH groups into a three-dimensional framework. O-H...O hydrogen bonds between the OH groups and the carboxylate O atoms are observed.

Comment top

The rational design and construction of coordination polymers based on metal ions and N-heterocyclic multicarboxylate ligands have attracted considerable attention for their intriguing structural topologies along with potential applications (Li et al., 2008; Mahata & Natarajan, 2005; Sun et al., 2001; Wang et al., 2009). In this paper, we report a cadmium complex with a three-dimensional framework based on 5-(4-carboxyphenyl)pyridine-2-carboxylic acid (H2L).

The asymmetric unit of the title compound contains two crystallographically independent CdII ions with different coordination geometries (Fig. 1). The Cd1 atom is six-coordinated by two O atoms from two L ligands and four µ3-OH groups in a distorted trigonal prismatic geometry. The Cd1—O bond lengths are in a range of 2.176 (4)–2.587 (4) Å. The Cd2 atom is five-coordinated by one N and two O atoms from two L ligands and two µ3-OH groups in a distorted square-pyramidal geometry. The Cd2—N bond length is 2.354 (4) Å and the Cd2—O bond lengths are in a range of 2.196 (4)–2.368 (4) Å. Interestingly, the carboxylate groups and hydroxy groups connect the CdII ions into a layer parallel to (011) and adjacent layers are further linked by the L ligands as pillars along the a-axis, generating a three-dimensional framework (Fig. 2). O—H···O hydrogen bonds between the hydroxy groups and carboxylate O atoms stabilize the structure (Table 1).

Related literature top

For related structures and applications of metal complexes with N-heterocyclic multicarboxylate ligands, see: Li et al. (2008); Mahata & Natarajan (2005); Sun et al. (2001); Wang et al. (2009). For the synthesis of the ligand, see: Ben & Gordon (1951); Liu et al. (2005).

Experimental top

The H2L ligand was prepared by a similar method described by Ben & Gordon (1951) and Liu et al. (2005). A precursor ligand, 2-methyl-5-p-tolylpyridine, was prepared through the Suzuki reaction between 4-methylphenylboronic acid (2.039 g, 15 mmol) and 5-bromo-2-methylpyridine (1.730 g, 10 mmol). The H2L ligand was obtained by the oxidation of potassium permanganate. The title compound was synthesized under hydrothermal conditions. A mixture of Cd(CH3CO2)2.2H2O (0.053 g, 0.2mmol) and H2L (0.024 g, 0.1 mmol) in methanol (2 ml) and distilled water (5 ml) was stirred for 20 min in air, and the pH value was adjusted to about 8.5 with 0.1M CH3COOH and 0.1M NaOH solutions. Then the mixture was sealed in a 23 ml Teflon-lined stainless steel autoclave, which was heated to 433 K for 72 h. After cooling to room temperature, colorless block crystals of the title compound suitable for X-ray diffraction were obtained.

Refinement top

C-bound H atoms were positioned geometrically and refined as riding atoms, with C—H = 0.93 Å and with Uiso(H) = 1.2Ueq(C). H atoms of hydroxy groups were located in a difference Fourier map and their positions were refined with bond-length restraints of 0.82 (1) Å, and with Uiso(H) = 1.5Ueq(O). The highest residual electron density was found at 0.96 Å from Cd1 atom and the deepest hole at 0.70 Å from Cd1 atom.

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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 of the title compound. Displacement ellipsoids are drawn at the 50% probability level. [Symmetry codes: (i) x, -1+y, z; (ii) 1-x, -1/2+y, 1/2-z; (iii) 1-x, 2-y, 1-z; (iv) 2-x, 1-y, 1-z; (v) x, 1+y, z.]
[Figure 2] Fig. 2. The packing diagram of the title compound, showing the three-dimensional framework.
Poly[di-µ3-hydroxy[µ4-5-(4-carboxyphenyl)pyridine-2-carboxylato- κ5N,O2:O2':O4:O4']dicadmium] top
Crystal data top
[Cd2(C13H7NO4)(OH)2]F(000) = 952
Mr = 500.03Dx = 2.665 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 2448 reflections
a = 15.4316 (17) Åθ = 2.1–26.0°
b = 3.8261 (4) ŵ = 3.44 mm1
c = 21.586 (2) ÅT = 293 K
β = 102.114 (2)°Block, colourless
V = 1246.1 (2) Å30.27 × 0.21 × 0.14 mm
Z = 4
Data collection top
Bruker APEX CCD
diffractometer
2448 independent reflections
Radiation source: fine-focus sealed tube2109 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.052
φ and ω scansθmax = 26.0°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
h = 1914
Tmin = 0.457, Tmax = 0.644k = 34
6277 measured reflectionsl = 2626
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)] = 0.037Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.087H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.0384P)2 + 3.8222P]
where P = (Fo2 + 2Fc2)/3
2448 reflections(Δ/σ)max = 0.001
205 parametersΔρmax = 1.82 e Å3
2 restraintsΔρmin = 1.36 e Å3
Crystal data top
[Cd2(C13H7NO4)(OH)2]V = 1246.1 (2) Å3
Mr = 500.03Z = 4
Monoclinic, P21/cMo Kα radiation
a = 15.4316 (17) ŵ = 3.44 mm1
b = 3.8261 (4) ÅT = 293 K
c = 21.586 (2) Å0.27 × 0.21 × 0.14 mm
β = 102.114 (2)°
Data collection top
Bruker APEX CCD
diffractometer
2448 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
2109 reflections with I > 2σ(I)
Tmin = 0.457, Tmax = 0.644Rint = 0.052
6277 measured reflectionsθmax = 26.0°
Refinement top
R[F2 > 2σ(F2)] = 0.037H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.087Δρmax = 1.82 e Å3
S = 1.04Δρmin = 1.36 e Å3
2448 reflectionsAbsolute structure: ?
205 parametersFlack parameter: ?
2 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*/Ueq
Cd10.54015 (3)0.60259 (12)0.317372 (18)0.02773 (14)
Cd20.63702 (3)1.00568 (11)0.464037 (18)0.02162 (14)
C10.6046 (4)1.0297 (15)0.6045 (3)0.0230 (12)
C20.6959 (3)0.8660 (15)0.6131 (3)0.0197 (11)
C30.7430 (3)0.7675 (16)0.6720 (3)0.0226 (12)
H30.71810.78370.70750.027*
C40.8292 (4)0.6427 (16)0.6769 (3)0.0251 (13)
H40.86290.58040.71630.030*
C50.8646 (3)0.6115 (14)0.6239 (3)0.0185 (11)
C60.8105 (3)0.7034 (16)0.5659 (3)0.0231 (12)
H60.83270.67580.52930.028*
C70.9584 (3)0.5045 (14)0.6255 (3)0.0185 (11)
C81.0268 (3)0.6001 (15)0.6757 (2)0.0216 (12)
H81.01390.71860.71030.026*
C91.1138 (3)0.5190 (15)0.6742 (3)0.0216 (12)
H91.15890.58830.70760.026*
C101.1350 (3)0.3358 (15)0.6238 (3)0.0216 (12)
C111.2310 (4)0.2519 (16)0.6218 (3)0.0241 (12)
C121.0658 (3)0.2371 (15)0.5748 (2)0.0224 (12)
H121.07820.10980.54100.027*
C130.9795 (4)0.3229 (16)0.5751 (3)0.0238 (13)
H130.93470.25830.54120.029*
N10.7283 (3)0.8293 (13)0.5604 (2)0.0224 (10)
O10.5713 (3)1.1503 (12)0.55044 (18)0.0330 (10)
O20.5712 (3)1.0362 (13)0.6518 (2)0.0408 (12)
O31.2893 (3)0.3539 (12)0.66625 (19)0.0342 (10)
O41.2417 (3)0.0784 (12)0.57409 (19)0.0324 (10)
O50.5786 (2)0.5013 (10)0.42462 (18)0.0197 (8)
H5A0.5284 (17)0.528 (16)0.430 (3)0.030*
O60.5682 (2)1.1069 (11)0.27639 (19)0.0238 (8)
H6A0.6206 (13)1.093 (18)0.275 (3)0.036*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cd10.0398 (3)0.0251 (3)0.0162 (2)0.00757 (19)0.00127 (18)0.00045 (18)
Cd20.0247 (2)0.0217 (2)0.0182 (2)0.00551 (16)0.00379 (16)0.00076 (16)
C10.020 (3)0.025 (3)0.025 (3)0.006 (2)0.006 (2)0.001 (2)
C20.017 (3)0.021 (3)0.023 (3)0.001 (2)0.008 (2)0.002 (2)
C30.021 (3)0.031 (3)0.018 (3)0.003 (2)0.009 (2)0.003 (2)
C40.025 (3)0.029 (3)0.020 (3)0.005 (2)0.002 (2)0.000 (3)
C50.016 (3)0.016 (3)0.024 (3)0.001 (2)0.005 (2)0.000 (2)
C60.019 (3)0.033 (3)0.018 (3)0.004 (2)0.005 (2)0.000 (3)
C70.014 (2)0.022 (3)0.021 (3)0.001 (2)0.007 (2)0.000 (2)
C80.022 (3)0.030 (3)0.015 (2)0.001 (2)0.007 (2)0.000 (2)
C90.018 (3)0.027 (3)0.019 (3)0.003 (2)0.001 (2)0.004 (2)
C100.020 (3)0.021 (3)0.026 (3)0.001 (2)0.010 (2)0.007 (2)
C110.023 (3)0.027 (3)0.024 (3)0.003 (2)0.008 (2)0.008 (3)
C120.023 (3)0.029 (3)0.018 (3)0.001 (2)0.008 (2)0.006 (3)
C130.020 (3)0.028 (3)0.022 (3)0.001 (2)0.001 (2)0.001 (2)
N10.018 (2)0.028 (3)0.022 (2)0.0040 (19)0.0048 (19)0.002 (2)
O10.027 (2)0.053 (3)0.020 (2)0.022 (2)0.0073 (17)0.008 (2)
O20.035 (2)0.064 (3)0.027 (2)0.025 (2)0.015 (2)0.010 (2)
O30.022 (2)0.049 (3)0.031 (2)0.006 (2)0.0018 (18)0.003 (2)
O40.028 (2)0.046 (3)0.026 (2)0.006 (2)0.0105 (18)0.004 (2)
O50.0139 (17)0.025 (2)0.0215 (19)0.0029 (15)0.0058 (15)0.0022 (16)
O60.0217 (19)0.023 (2)0.028 (2)0.0027 (17)0.0088 (17)0.0046 (18)
Geometric parameters (Å, º) top
Cd1—O6i2.174 (4)C6—H60.9300
Cd1—O62.203 (4)C7—C131.384 (8)
Cd1—O52.299 (4)C7—C81.393 (7)
Cd1—O6ii2.339 (4)C8—C91.385 (7)
Cd1—O2iii2.405 (4)C8—H80.9300
Cd1—O3iv2.586 (4)C9—C101.391 (8)
Cd2—O5v2.193 (4)C9—H90.9300
Cd2—O4iv2.221 (4)C10—C121.388 (7)
Cd2—O52.222 (4)C10—C111.525 (7)
Cd2—N12.354 (4)C11—O31.233 (7)
Cd2—O12.368 (4)C11—O41.264 (7)
C1—O21.237 (7)C12—C131.373 (7)
C1—O11.261 (7)C12—H120.9300
C1—C21.517 (7)C13—H130.9300
C2—N11.342 (7)O2—Cd1iii2.405 (4)
C2—C31.377 (7)O3—Cd1iv2.586 (4)
C3—C41.396 (7)O4—Cd2iv2.221 (4)
C3—H30.9300O5—Cd2i2.193 (4)
C4—C51.372 (8)O5—H5A0.814 (10)
C4—H40.9300O6—Cd1v2.174 (4)
C5—C61.396 (7)O6—Cd1vi2.339 (4)
C5—C71.498 (7)O6—H6A0.817 (10)
C6—N11.339 (7)
O6i—Cd1—O6121.88 (18)C5—C6—H6118.4
O6i—Cd1—O5103.38 (14)C13—C7—C8118.5 (5)
O6—Cd1—O5121.41 (14)C13—C7—C5120.3 (5)
O6i—Cd1—O6ii79.70 (13)C8—C7—C5121.1 (5)
O6—Cd1—O6ii79.12 (13)C9—C8—C7120.2 (5)
O5—Cd1—O6ii149.21 (13)C9—C8—H8119.9
O6i—Cd1—O2iii145.94 (16)C7—C8—H8119.9
O6—Cd1—O2iii79.60 (15)C8—C9—C10121.3 (5)
O5—Cd1—O2iii82.34 (13)C8—C9—H9119.4
O6ii—Cd1—O2iii79.22 (14)C10—C9—H9119.4
O6i—Cd1—O3iv80.11 (14)C12—C10—C9117.6 (5)
O6—Cd1—O3iv73.66 (14)C12—C10—C11121.2 (5)
O5—Cd1—O3iv80.39 (13)C9—C10—C11121.2 (5)
O6ii—Cd1—O3iv129.78 (13)O3—C11—O4127.0 (5)
O2iii—Cd1—O3iv133.69 (16)O3—C11—C10117.7 (5)
O5v—Cd2—O4iv106.95 (15)O4—C11—C10115.3 (5)
O5v—Cd2—O5120.10 (16)C13—C12—C10121.5 (5)
O4iv—Cd2—O592.19 (15)C13—C12—H12119.2
O5v—Cd2—N1135.39 (16)C10—C12—H12119.2
O4iv—Cd2—N183.77 (15)C12—C13—C7120.8 (5)
O5—Cd2—N1102.06 (15)C12—C13—H13119.6
O5v—Cd2—O183.94 (14)C7—C13—H13119.6
O4iv—Cd2—O1149.23 (14)C6—N1—C2118.5 (5)
O5—Cd2—O1107.35 (16)C6—N1—Cd2124.1 (4)
N1—Cd2—O169.28 (14)C2—N1—Cd2117.3 (3)
O2—C1—O1126.7 (5)C1—O1—Cd2119.1 (3)
O2—C1—C2116.5 (5)C1—O2—Cd1iii133.3 (4)
O1—C1—C2116.8 (5)C11—O3—Cd1iv133.0 (4)
N1—C2—C3122.3 (5)C11—O4—Cd2iv129.9 (4)
N1—C2—C1116.2 (5)Cd2i—O5—Cd2120.10 (16)
C3—C2—C1121.5 (5)Cd2i—O5—Cd1122.32 (17)
C2—C3—C4118.3 (5)Cd2—O5—Cd1103.73 (15)
C2—C3—H3120.9Cd2i—O5—H5A112 (5)
C4—C3—H3120.9Cd2—O5—H5A99 (5)
C5—C4—C3120.4 (5)Cd1—O5—H5A94 (4)
C5—C4—H4119.8Cd1v—O6—Cd1121.87 (18)
C3—C4—H4119.8Cd1v—O6—Cd1vi101.02 (15)
C4—C5—C6117.2 (5)Cd1—O6—Cd1vi100.16 (15)
C4—C5—C7123.8 (5)Cd1v—O6—H6A111 (5)
C6—C5—C7118.8 (5)Cd1—O6—H6A104 (5)
N1—C6—C5123.1 (5)Cd1vi—O6—H6A120 (5)
N1—C6—H6118.4
O2—C1—C2—N1173.9 (6)O1—Cd2—N1—C25.9 (4)
O1—C1—C2—N17.3 (8)O2—C1—O1—Cd2168.3 (5)
O2—C1—C2—C37.3 (8)C2—C1—O1—Cd213.0 (7)
O1—C1—C2—C3171.5 (6)O5v—Cd2—O1—C1154.0 (5)
N1—C2—C3—C43.5 (9)O4iv—Cd2—O1—C140.8 (6)
C1—C2—C3—C4175.3 (5)O5—Cd2—O1—C186.3 (5)
C2—C3—C4—C51.7 (9)N1—Cd2—O1—C110.4 (4)
C3—C4—C5—C61.1 (9)O1—C1—O2—Cd1iii22.3 (10)
C3—C4—C5—C7175.5 (5)C2—C1—O2—Cd1iii156.4 (4)
C4—C5—C6—N12.3 (9)O4—C11—O3—Cd1iv13.6 (10)
C7—C5—C6—N1174.4 (5)C10—C11—O3—Cd1iv167.4 (4)
C4—C5—C7—C13149.3 (6)O3—C11—O4—Cd2iv17.1 (9)
C6—C5—C7—C1334.2 (8)C10—C11—O4—Cd2iv163.9 (4)
C4—C5—C7—C834.0 (8)O5v—Cd2—O5—Cd2i179.992 (1)
C6—C5—C7—C8142.5 (6)O4iv—Cd2—O5—Cd2i69.0 (2)
C13—C7—C8—C91.1 (8)N1—Cd2—O5—Cd2i15.1 (2)
C5—C7—C8—C9175.6 (5)O1—Cd2—O5—Cd2i86.94 (19)
C7—C8—C9—C101.3 (9)O5v—Cd2—O5—Cd139.0 (3)
C8—C9—C10—C120.0 (8)O4iv—Cd2—O5—Cd172.10 (16)
C8—C9—C10—C11179.0 (5)N1—Cd2—O5—Cd1156.20 (15)
C12—C10—C11—O3178.5 (6)O1—Cd2—O5—Cd1132.00 (14)
C9—C10—C11—O30.4 (8)O6i—Cd1—O5—Cd2i3.5 (2)
C12—C10—C11—O42.4 (8)O6—Cd1—O5—Cd2i137.88 (18)
C9—C10—C11—O4178.7 (5)O6ii—Cd1—O5—Cd2i95.8 (3)
C9—C10—C12—C131.4 (9)O2iii—Cd1—O5—Cd2i149.3 (2)
C11—C10—C12—C13177.6 (5)O3iv—Cd1—O5—Cd2i73.8 (2)
C10—C12—C13—C71.6 (9)O6i—Cd1—O5—Cd2143.42 (15)
C8—C7—C13—C120.3 (9)O6—Cd1—O5—Cd22.1 (2)
C5—C7—C13—C12177.1 (5)O6ii—Cd1—O5—Cd2124.3 (2)
C5—C6—N1—C20.7 (9)O2iii—Cd1—O5—Cd270.76 (17)
C5—C6—N1—Cd2177.7 (4)O3iv—Cd1—O5—Cd266.10 (15)
C3—C2—N1—C62.3 (9)O6i—Cd1—O6—Cd1v180.0
C1—C2—N1—C6176.5 (5)O5—Cd1—O6—Cd1v45.7 (2)
C3—C2—N1—Cd2179.2 (4)O6ii—Cd1—O6—Cd1v109.5 (2)
C1—C2—N1—Cd22.0 (6)O2iii—Cd1—O6—Cd1v28.6 (2)
O5v—Cd2—N1—C6115.5 (5)O3iv—Cd1—O6—Cd1v113.2 (2)
O4iv—Cd2—N1—C67.7 (5)O6i—Cd1—O6—Cd1vi70.1 (2)
O5—Cd2—N1—C683.3 (5)O5—Cd1—O6—Cd1vi155.55 (12)
O1—Cd2—N1—C6172.6 (5)O6ii—Cd1—O6—Cd1vi0.37 (9)
O5v—Cd2—N1—C262.9 (5)O2iii—Cd1—O6—Cd1vi81.26 (15)
O4iv—Cd2—N1—C2170.8 (4)O3iv—Cd1—O6—Cd1vi136.96 (17)
O5—Cd2—N1—C298.3 (4)
Symmetry codes: (i) x, y1, z; (ii) x+1, y1/2, z+1/2; (iii) x+1, y+2, z+1; (iv) x+2, y+1, z+1; (v) x, y+1, z; (vi) x+1, y+1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O5—H5A···O1iii0.81 (3)2.08 (4)2.818 (6)150 (6)
O6—H6A···O3iv0.82 (2)2.39 (4)2.887 (6)120 (6)
Symmetry codes: (iii) x+1, y+2, z+1; (iv) x+2, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O5—H5A···O1i0.81 (3)2.08 (4)2.818 (6)150 (6)
O6—H6A···O3ii0.82 (2)2.39 (4)2.887 (6)120 (6)
Symmetry codes: (i) x+1, y+2, z+1; (ii) x+2, y+1, z+1.
Acknowledgements top

We are thankful for support from the State Key Laboratory of Electroanalytical Chemistry, Changchun, China.

references
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