supplementary materials


xu5394 scheme

Acta Cryst. (2012). E68, m84-m85    [ doi:10.1107/S1600536811054183 ]

Poly[(2,2'-bipyridine-[kappa]2N,N')([mu]3-2,4,6-trimethylisophthalato-[kappa]5O1,O1':O1:O3,O3')cadmium]

S.-G. Hou and M.-F. Jin

Abstract top

In the crystal structure of the polymeric title complex, [Cd(C11H10O4)(C10H8N2)]n, the CdII cation is chelated by one 2,2-bipyridine ligand and two carboxyl groups from two trimethylisophthalate (TMIPA) anions, and is further coordinated by one carboxylate O atom from a third TMIPA anion, forming a distorted pentagonal-bipyramidal geometry. Each TMIPA anion bridges three CdII cations, forming polymeric complex sheets parallel to (001). Weak C-H...O hydrogen bonding occurs between adjacent sheets.

Comment top

The rational design and synthesis of functional metal-organic frameworks (MOFs) is a more and more fascinating field in recent years due to their interesting topologies and potential applications in gas adsorption, nonlinear optics, magnetism, molecular recognition, etc (Evans & Lin, 2002; Chen, et al., 2010; Leong & Vittal, 2011; Sun et al., 2011). As we know, the construction of MOFs mainly depends on the coordination geometry of metal ions and the nature of ligands. Besides, some secondary interactions, such as aromatic π···π interactions, classical hydrogen bonds (such as O-H···O and N-H···O hydrogen bonds), and non-classical hydrogen bonds (such as C-H···O hydrogen bond) often influence the packing of molecules from discrete subunits or low-dimentional entities to high-dimentional supramolecular frameworks. One of the most effective strategies to assemble MOFs is to use carboxylates as linkers because of their diverse conformations and coordination modes observed in the coordination process (Ma et al., 2008; Zhang et al., 2008). In spite of isophthalate-based MOFs (Zhou et al., 2003; Zhang et al., 2003) have been widely reported, to the best of our knowledge, only one MOF based on 2,4,6,-trimethylisophthalic acid (H2TMIPA) has been documented until now (He et al., 2010). Based on our previous work (Dai et al., 2008; Dai et al., 2009; Zhao et al., 2009) and consideration the steric hindrance effects of additional three methyl groups on isophthalate, herein, we choose the H2TMIPA as a bridging ligand to construct a novel CdII coordination polymer (I), which is a 2D (4,4) net incorporating [Cd2(COO)4N2] SBUs.

The asymmetric unit of (I) contains one crystallographically independent CdII center, one TMIPA ligand and one bpy ligand. The CdII ion is in a slightly distorted pentagonal bipyramidal geometry, completed by five O atoms from three different TMIPA ligands and two N atoms from the same bpy ligand (Fig. 1). The equatorial plane of pentagonal bipyramid is defined by O2i, O3ii, O4ii, N2 atoms, while the axial positions are occupied N1, O1 atoms. [symmetry codes: (i) -x+1, -y+1, -z+1; (ii) -x+3/2, y+1/2, z]. Two carboxyl groups on TMIPA ligand adopt two different coordination patterns, µ1-η1: η1 chelating and µ2-η2: η1 bridging, respectively. The Cd-N bond lengths are 2.393 (4) and 2.334 (4) Å, while the Cd-O bond lengths vary from 2.317 (3) to 2.607 (3) Å (Table). The average Cd-N and Cd-O distances in (I) are comparable with those reported for Cd-based MOFs (Liu et al., 2008). Two crystallographically equivalent CdII anions are bridged by two tridentate bridging carboxyl groups to form a binuclear SBU with a Cd···Cd contact of 3.7886 (6) Å. Because of the steric hindrance between the methyl and the carboxyl groups, the two carboxyl groups of H2TMIPA are not coplanar with the central benzene ring, generating two dihedral angles of 55.1 (2) and 85.3 (2)o, respectively. The [Cd2(COO)4N2] SBUs are joined by TMIPA ligands to form an infinite 1D zigzag chain. Furthermore, TMIPA ligands connect the zigzag chain to a 2D layer (Fig. 2) which is consolidated by the intrasheet weak face-to-face π···π interaction between bpy and TMIPA with Cg1···Cg2i separation of 3.725 (3) Å (Cg1 and Cg2 are the centroids of the N1/C1–C5 and C12–C17 rings, respectively; symmetry code: (i) -x+1, -y+1, -z+1). The bpy ligand acts as a terminal group to occupy the remaining coordinate sites, which prevents the structure from higher dimensionalities. The adjacent 2D layers are further extended to a 3D supramolecular framework by virtue of non-classical C-H···O hydrogen bonds (Table 2).

Related literature top

For applications of functional metal-organic frameworks, see: Evans & Lin (2002); Chen et al. (2010); Leong & Vittal (2011); Sun et al. (2011). For related structures, see: Ma et al. (2008); Zhang et al. (2008); Zhou et al. (2003); Zhang et al. (2003); He et al. (2010); Liu et al. (2008). For our previous work, see: Dai et al. (2008, 2009); Zhao et al. (2009).

Experimental top

A mixture of Cd(NO3)2.6H2O (30 mg, 0.12 mmol), 2,4,6,-trimethylisophthalic acid (H2TMIPA) (20 mg, 0.12 mmol) and bipyridine (10 mg, 0.06 mmol) was suspended in 15 mL mixed solvents of N,N'-dimethylformamide, ethanol and H2O (v/v = 1:1:1), and heated in a Teflon-lined steel bomb at 373 K for 4 days. After cooling to room temperature, colorless crystals were collected, washed with ethanol several times, and dried in the air (yield: 47%, based on H2TMIPA).

Refinement top

H atoms were generated geometrically and were allowed to ride on their parent atoms in the riding model approximations with C—H = 0.93 (aromatic) and 0.96 Å (methyl), Uiso(H) = 1.2Ueq(C) for aromatic H atoms and 1.5Ueq(C) for methyl H atoms.

Computing details top

Data collection: APEX2 (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: DIAMOND (Brandenburg, 2008); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The structure of (I), showing the atom-numbering scheme and the coordination environment around the CdII centre. Displacement ellipsoids are drawn at 50% probability level and H atoms are shown as small spheres of arbitrary radii. (symmetry codes: (i) -x+1, -y+1, -z+1; (ii) -x+3/2, y+1/2, z)
[Figure 2] Fig. 2. A ball-and-stick perspective view of the 2D sheet incorporating weak face-to-face π···π interaction (green dashed lines). Hydrogen atoms are omitted for clarity.
Poly[(2,2'-bipyridine-κ2N,N')(µ3-2,4,6- trimethylisophthalato- κ5O1,O1':O1:O3,O3')cadmium] top
Crystal data top
[Cd(C11H10O4)(C10H8N2)]F(000) = 1904
Mr = 474.77Dx = 1.687 Mg m3
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 5089 reflections
a = 13.1985 (8) Åθ = 2.2–27.8°
b = 15.5714 (9) ŵ = 1.20 mm1
c = 18.1926 (11) ÅT = 298 K
V = 3738.9 (4) Å3Block, colorless
Z = 80.15 × 0.10 × 0.10 mm
Data collection top
Bruker SMART APEXII CCD
diffractometer
4299 independent reflections
Radiation source: fine-focus sealed tube2454 reflections with I > 2σ(I)
graphiteRint = 0.054
ω and φ scansθmax = 27.6°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
h = 1711
Tmin = 0.841, Tmax = 0.890k = 1720
14349 measured reflectionsl = 1523
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)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.098H-atom parameters constrained
S = 0.99 w = 1/[σ2(Fo2) + (0.0375P)2]
where P = (Fo2 + 2Fc2)/3
4299 reflections(Δ/σ)max = 0.001
253 parametersΔρmax = 0.51 e Å3
0 restraintsΔρmin = 0.63 e Å3
Crystal data top
[Cd(C11H10O4)(C10H8N2)]V = 3738.9 (4) Å3
Mr = 474.77Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 13.1985 (8) ŵ = 1.20 mm1
b = 15.5714 (9) ÅT = 298 K
c = 18.1926 (11) Å0.15 × 0.10 × 0.10 mm
Data collection top
Bruker SMART APEXII CCD
diffractometer
4299 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
2454 reflections with I > 2σ(I)
Tmin = 0.841, Tmax = 0.890Rint = 0.054
14349 measured reflectionsθmax = 27.6°
Refinement top
R[F2 > 2σ(F2)] = 0.045H-atom parameters constrained
wR(F2) = 0.098Δρmax = 0.51 e Å3
S = 0.99Δρmin = 0.63 e Å3
4299 reflectionsAbsolute structure: ?
253 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*/Ueq
Cd10.50573 (2)0.584163 (18)0.575068 (16)0.03177 (11)
C10.3060 (4)0.7000 (3)0.6257 (3)0.0496 (14)
H1A0.32180.72910.58260.060*
C20.2259 (4)0.7293 (3)0.6667 (3)0.0569 (15)
H2A0.18730.77580.65120.068*
C30.2046 (4)0.6877 (3)0.7314 (3)0.0634 (16)
H3A0.15180.70640.76130.076*
C40.2620 (4)0.6187 (3)0.7511 (3)0.0586 (15)
H4A0.24890.59030.79510.070*
C50.3391 (3)0.5909 (3)0.7063 (2)0.0385 (11)
C60.4024 (4)0.5140 (3)0.7238 (2)0.0396 (11)
C70.3857 (4)0.4630 (3)0.7852 (3)0.0471 (13)
H7A0.33460.47680.81830.057*
C80.4453 (4)0.3916 (3)0.7965 (3)0.0541 (15)
H8A0.43520.35730.83770.065*
C90.5189 (4)0.3718 (3)0.7472 (3)0.0622 (16)
H9A0.55900.32320.75330.075*
C100.5323 (5)0.4249 (4)0.6888 (3)0.082 (2)
H10A0.58350.41160.65550.098*
C110.6847 (3)0.4899 (3)0.5399 (2)0.0311 (10)
C120.7761 (3)0.4466 (3)0.5081 (2)0.0335 (11)
C130.8065 (3)0.3639 (3)0.5314 (2)0.0344 (11)
C140.8932 (3)0.3269 (3)0.5012 (3)0.0387 (12)
C150.9490 (4)0.3712 (3)0.4471 (3)0.0581 (16)
C160.9164 (4)0.4521 (3)0.4247 (3)0.0699 (18)
H16A0.95290.48130.38880.084*
C170.8299 (4)0.4907 (3)0.4549 (3)0.0543 (15)
C180.7974 (5)0.5776 (3)0.4262 (3)0.078 (2)
H18A0.73810.59640.45220.117*
H18B0.78230.57330.37470.117*
H18C0.85110.61830.43340.117*
C190.7417 (4)0.3160 (3)0.5853 (3)0.0456 (13)
H19A0.77170.26110.59550.068*
H19B0.67530.30780.56480.068*
H19C0.73650.34830.63010.068*
C200.9284 (3)0.2395 (3)0.5264 (3)0.0417 (12)
C211.0421 (5)0.3344 (4)0.4112 (4)0.097 (3)
H21A1.06830.37480.37610.146*
H21B1.02490.28190.38660.146*
H21C1.09260.32320.44790.146*
N10.3624 (3)0.6324 (2)0.64418 (19)0.0367 (9)
N20.4764 (3)0.4950 (3)0.6760 (2)0.0532 (12)
O10.6951 (3)0.5405 (2)0.59115 (17)0.0536 (9)
O20.5988 (2)0.47532 (18)0.51372 (16)0.0412 (8)
O30.9433 (3)0.2269 (2)0.5937 (2)0.0580 (10)
O40.9409 (3)0.18136 (19)0.48063 (19)0.0618 (11)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cd10.0381 (2)0.02748 (17)0.02972 (17)0.00141 (17)0.00347 (18)0.00099 (13)
C10.059 (4)0.047 (3)0.043 (3)0.003 (3)0.007 (3)0.009 (2)
C20.056 (4)0.048 (3)0.067 (4)0.008 (3)0.011 (3)0.005 (3)
C30.061 (4)0.063 (4)0.066 (4)0.016 (3)0.021 (3)0.002 (3)
C40.063 (4)0.059 (3)0.054 (3)0.017 (3)0.019 (3)0.017 (3)
C50.040 (3)0.041 (3)0.035 (3)0.001 (3)0.006 (2)0.001 (2)
C60.044 (3)0.038 (3)0.038 (3)0.001 (2)0.002 (2)0.002 (2)
C70.051 (3)0.047 (3)0.044 (3)0.004 (3)0.015 (3)0.011 (2)
C80.060 (4)0.047 (3)0.054 (4)0.011 (3)0.002 (3)0.021 (3)
C90.068 (4)0.048 (3)0.070 (4)0.019 (3)0.009 (3)0.022 (3)
C100.098 (5)0.065 (4)0.082 (5)0.040 (4)0.044 (4)0.033 (3)
C110.029 (3)0.026 (2)0.038 (3)0.004 (2)0.002 (2)0.007 (2)
C120.033 (3)0.027 (2)0.040 (3)0.000 (2)0.003 (2)0.005 (2)
C130.025 (3)0.031 (2)0.047 (3)0.004 (2)0.006 (2)0.001 (2)
C140.026 (3)0.030 (2)0.061 (3)0.003 (2)0.003 (2)0.001 (2)
C150.041 (3)0.044 (3)0.089 (4)0.010 (3)0.021 (3)0.010 (3)
C160.055 (4)0.048 (3)0.106 (5)0.014 (3)0.040 (4)0.034 (3)
C170.045 (3)0.039 (3)0.079 (4)0.014 (3)0.015 (3)0.009 (3)
C180.084 (5)0.049 (3)0.102 (5)0.020 (3)0.036 (4)0.029 (3)
C190.035 (3)0.038 (3)0.064 (3)0.000 (2)0.000 (3)0.008 (2)
C200.034 (3)0.027 (3)0.064 (4)0.002 (2)0.002 (3)0.004 (3)
C210.069 (4)0.071 (4)0.152 (7)0.034 (4)0.063 (5)0.032 (4)
N10.044 (3)0.030 (2)0.036 (2)0.002 (2)0.0083 (19)0.0022 (17)
N20.065 (3)0.046 (2)0.048 (3)0.019 (2)0.022 (2)0.016 (2)
O10.049 (2)0.061 (2)0.051 (2)0.0074 (19)0.0078 (18)0.0182 (18)
O20.0239 (18)0.0478 (19)0.052 (2)0.0033 (16)0.0045 (16)0.0085 (15)
O30.072 (3)0.038 (2)0.064 (3)0.0192 (19)0.023 (2)0.0055 (17)
O40.092 (3)0.0328 (19)0.061 (2)0.017 (2)0.010 (2)0.0006 (17)
Geometric parameters (Å, °) top
Cd1—N12.393 (4)C11—O21.250 (5)
Cd1—N22.334 (4)C11—C121.499 (6)
Cd1—O12.607 (3)C12—C171.382 (6)
Cd1—O2i2.317 (3)C12—C131.414 (5)
Cd1—O22.372 (3)C13—C141.394 (6)
Cd1—O3ii2.347 (3)C13—C191.500 (6)
Cd1—O4ii2.396 (3)C14—C151.409 (6)
C1—N11.333 (5)C14—C201.510 (6)
C1—C21.371 (6)C15—C161.392 (7)
C1—H1A0.9300C15—C211.505 (7)
C2—C31.372 (6)C16—C171.402 (7)
C2—H2A0.9300C16—H16A0.9300
C3—C41.363 (7)C17—C181.514 (6)
C3—H3A0.9300C18—H18A0.9600
C4—C51.374 (6)C18—H18B0.9600
C4—H4A0.9300C18—H18C0.9600
C5—N11.338 (5)C19—H19A0.9600
C5—C61.494 (6)C19—H19B0.9600
C6—N21.341 (5)C19—H19C0.9600
C6—C71.388 (6)C20—O41.241 (5)
C7—C81.377 (6)C20—O31.255 (5)
C7—H7A0.9300C20—Cd1iii2.718 (4)
C8—C91.357 (7)C21—H21A0.9600
C8—H8A0.9300C21—H21B0.9600
C9—C101.359 (7)C21—H21C0.9600
C9—H9A0.9300O2—Cd1i2.317 (3)
C10—N21.339 (6)O3—Cd1iii2.347 (3)
C10—H10A0.9300O4—Cd1iii2.396 (3)
C11—O11.228 (5)
O2i—Cd1—N2102.23 (14)O1—C11—O2120.5 (4)
O2i—Cd1—O3ii130.54 (12)O1—C11—C12119.5 (4)
N2—Cd1—O3ii119.81 (14)O2—C11—C12120.0 (4)
O2i—Cd1—O272.22 (12)C17—C12—C13121.1 (4)
N2—Cd1—O291.79 (12)C17—C12—C11117.4 (4)
O3ii—Cd1—O2126.60 (12)C13—C12—C11121.5 (4)
O2i—Cd1—N191.21 (11)C14—C13—C12119.4 (4)
N2—Cd1—N169.02 (13)C14—C13—C19121.4 (4)
O3ii—Cd1—N181.58 (12)C12—C13—C19119.1 (4)
O2—Cd1—N1151.76 (11)C13—C14—C15120.2 (4)
O2i—Cd1—O4ii85.85 (11)C13—C14—C20120.3 (4)
N2—Cd1—O4ii171.39 (14)C15—C14—C20119.5 (4)
O3ii—Cd1—O4ii54.62 (11)C16—C15—C14119.0 (5)
O2—Cd1—O4ii87.81 (12)C16—C15—C21118.0 (5)
N1—Cd1—O4ii114.27 (12)C14—C15—C21123.0 (5)
O2i—Cd1—O1123.00 (10)C15—C16—C17121.6 (5)
N2—Cd1—O185.17 (13)C15—C16—H16A119.2
O3ii—Cd1—O187.47 (12)C17—C16—H16A119.2
O2—Cd1—O150.95 (10)C12—C17—C16118.7 (4)
N1—Cd1—O1141.36 (11)C12—C17—C18122.7 (4)
O4ii—Cd1—O187.91 (12)C16—C17—C18118.6 (5)
O2i—Cd1—C20ii108.60 (14)C17—C18—H18A109.5
N2—Cd1—C20ii146.97 (16)C17—C18—H18B109.5
O3ii—Cd1—C20ii27.47 (12)H18A—C18—H18B109.5
O2—Cd1—C20ii108.48 (13)C17—C18—H18C109.5
N1—Cd1—C20ii98.32 (13)H18A—C18—H18C109.5
O4ii—Cd1—C20ii27.16 (12)H18B—C18—H18C109.5
O1—Cd1—C20ii87.82 (12)C13—C19—H19A109.5
N1—C1—C2123.8 (4)C13—C19—H19B109.5
N1—C1—H1A118.1H19A—C19—H19B109.5
C2—C1—H1A118.1C13—C19—H19C109.5
C1—C2—C3117.9 (5)H19A—C19—H19C109.5
C1—C2—H2A121.1H19B—C19—H19C109.5
C3—C2—H2A121.1O4—C20—O3121.3 (4)
C4—C3—C2118.9 (5)O4—C20—C14119.6 (5)
C4—C3—H3A120.5O3—C20—C14119.0 (4)
C2—C3—H3A120.5O4—C20—Cd1iii61.8 (2)
C3—C4—C5120.3 (5)O3—C20—Cd1iii59.6 (2)
C3—C4—H4A119.9C14—C20—Cd1iii178.4 (4)
C5—C4—H4A119.9C15—C21—H21A109.5
N1—C5—C4121.2 (4)C15—C21—H21B109.5
N1—C5—C6116.1 (4)H21A—C21—H21B109.5
C4—C5—C6122.7 (4)C15—C21—H21C109.5
N2—C6—C7120.8 (4)H21A—C21—H21C109.5
N2—C6—C5116.4 (4)H21B—C21—H21C109.5
C7—C6—C5122.8 (4)C1—N1—C5117.8 (4)
C8—C7—C6119.4 (5)C1—N1—Cd1123.9 (3)
C8—C7—H7A120.3C5—N1—Cd1118.3 (3)
C6—C7—H7A120.3C10—N2—C6117.9 (4)
C9—C8—C7119.6 (5)C10—N2—Cd1122.0 (3)
C9—C8—H8A120.2C6—N2—Cd1120.0 (3)
C7—C8—H8A120.2C11—O1—Cd188.5 (3)
C10—C9—C8118.1 (5)C11—O2—Cd1i151.4 (3)
C10—C9—H9A120.9C11—O2—Cd199.2 (3)
C8—C9—H9A120.9Cd1i—O2—Cd1107.78 (12)
N2—C10—C9124.1 (5)C20—O3—Cd1iii93.0 (3)
N2—C10—H10A118.0C20—O4—Cd1iii91.1 (3)
C9—C10—H10A118.0
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+3/2, y+1/2, z; (iii) −x+3/2, y−1/2, z.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C4—H4A···O1iv0.932.323.240 (6)169
C8—H8A···O3iv0.932.393.251 (6)155
Symmetry codes: (iv) x−1/2, y, −z+3/2.
Table 1
Selected geometric parameters (Å)
top
Cd1—N12.393 (4)Cd1—O22.372 (3)
Cd1—N22.334 (4)Cd1—O3ii2.347 (3)
Cd1—O12.607 (3)Cd1—O4ii2.396 (3)
Cd1—O2i2.317 (3)
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+3/2, y+1/2, z.
Table 2
Hydrogen-bond geometry (Å, °)
top
D—H···AD—HH···AD···AD—H···A
C4—H4A···O1iii0.932.323.240 (6)169
C8—H8A···O3iii0.932.393.251 (6)155
Symmetry codes: (iii) x−1/2, y, −z+3/2.
Acknowledgements top

This work was supported financially by Anyang Institute of Technology, China.

references
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