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Acta Crystallogr Sect E Struct Rep Online. 2010 July 1; 66(Pt 7): m743.
Published online 2010 June 5. doi:  10.1107/S1600536810020714
PMCID: PMC3006793

Bis{4,4′-[oxalylbis(aza­nedi­yl)]dipyridinium} octa­molybdate

Abstract

In the crystal structure of the title compound, (C12H12N4O2)2[Mo8O26], the amino and pyridinium groups of the N 1,N 2-di(pyridinium-4-yl)oxalamide cations are hydrogen bonded to the O atoms of the centrosymmetric isopolyoxometalate β-[Mo8O26]4− anions, forming a three-dimensional supra­molecular architecture.

Related literature

For polyoxometalates (POMs), see: Cronin et al. (2002 [triangle]); Fukaya & Yamase (2003 [triangle]); Katsoulis (1988 [triangle]); Pope & Müller (1991 [triangle]). For the applications of POMs in biology and materials sciences, see: Cui et al. (2003 [triangle]); Luan et al. (2002 [triangle]); Wang et al. (2003 [triangle]). For the structure of N 1,N 2-di(pyridin-4-yl)oxalamide, see: Tzeng et al. (2007 [triangle]). For details of the geometrical parameters in the same isopolyoxometalate anion, see: Gong et al. (2007 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-0m743-scheme1.jpg

Experimental

Crystal data

  • (C12H12N4O2)2[Mo8O26]
  • M r = 1672.03
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-0m743-efi1.jpg
  • a = 10.633 (2) Å
  • b = 11.552 (2) Å
  • c = 17.240 (4) Å
  • β = 101.553 (3)°
  • V = 2074.7 (8) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 2.45 mm−1
  • T = 293 K
  • 0.23 × 0.22 × 0.05 mm

Data collection

  • Siemens SMART CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.829, T max = 1.000
  • 14669 measured reflections
  • 4534 independent reflections
  • 4215 reflections with I > 2σ(I)
  • R int = 0.021

Refinement

  • R[F 2 > 2σ(F 2)] = 0.022
  • wR(F 2) = 0.098
  • S = 1.40
  • 4534 reflections
  • 316 parameters
  • H-atom parameters constrained
  • Δρmax = 1.40 e Å−3
  • Δρmin = −2.27 e Å−3

Data collection: SMART (Siemens, 1996 [triangle]); cell refinement: SAINT (Siemens, 1996 [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: SHELXTL.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810020714/su2182sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810020714/su2182Isup2.hkl

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

Acknowledgments

This work was supported by the Chongqing University Postgraduate Science Fund (No. 200911A1B0010317) and the Fundamental Research Funds for the Central Universities (No. CDJZR10 22 00 09)

supplementary crystallographic information

Comment

Polyoxometalates (POMs) are early transition metal oxygen anion clusters. They are an outstanding class of anionic compounds due to their wealthy topology, superior physical and chemical properties (Pope & Muller, 1991; Katsoulis, 1988). The nanoscopic sizes (Cronin, et al., 2002; Fukaya & Yamase, 2003,) and thier diversified shapes of discrete POMs have attracted great interest. The design, synthesis and structural characterization of inorganic-organic hybrid compounds base on POMs, for which many properties and applications can be predicted, have established a new field of research in the chemistry of biology and materials sciences (Luan, et al., 2002; Cui, et al., 2003; Wang, et al., 2003). Different N-heterocycle ligands can lead to different inorganic-organic hybrid compounds based on POMs. N1,N2-di(pyridin-4-yl)oxalamide (L), is a bis-pyridine ligand, which has been reported only rarely in the construction of hybrid compounds based on POMs. In the present work, the title complex was synthesized hydrothermally by reacting L with the isopolyoxometalate, Mo8O26.

The molecular structure of the title complex is illustrated in Fig. 1. In the asymmetric unit there is a doublely protonated L molecule, and half an isopolyoxometalate unit. The bond distances and angles in the cation are similar to those observed previously for N1,N2-di(pyridin-4-yl)oxalamide (Tzeng, et al., 2007). For the anion, [Mo8O26]4-, the geometrical parameters are similar to those reported by (Gong, et al., 2007).

In the crystal the protonated pyrdidinium groups and the amino group form N-H···O hydrogen bonds with the oxygen atoms of the centrosymmetric [Mo8O26]4- anions, leading to the formation of a three dimensional supramolecular network (Table 1 and Fig. 2).

Experimental

A mixture of L (0.05 mmol, 0.012 g), Na2MoO4(0.05 mmol, 0.012 g) and water(10 ml) was adjusted to pH = 3.0 by HCl. The synthesis was carried out hydrothermally using a Teflon-lined autoclave. The reaction mixture was heated at 393 K for 3 days, followed by slow cooling to rt. The resulting colorless prismatic crystals were filtered off and washed with water (yield: ca. 90% based on Mo). Elemental analyse - found: C, 17.45; H, 1.58; N, 6.56; Mo, 46.11; calcd: C, 17.22; H, 1.44; N, 6.70; Mo, 45.93.

Refinement

The H-atoms were positioned geometrically and refined as riding atoms: C—H = 0.93Å, N—H = 0.86Å and Uiso(H) = 1.2Ueq(N,C).

Figures

Fig. 1.
The molecular structure of the title complex, with the atomic numbering scheme and displacement ellipsoids at the 30% probability level [Symmetry codes: (i) -x,-y+1,-z].
Fig. 2.
A view along the b-axis of the crystal packing of the title complex, illustrating the three dimensional supramolecular architecture constructed by the intermolecular N-H···O hydrogen bonds (dotted lines); see Table 1 for details. ...

Crystal data

(C12H12N4O2)2[Mo8O26]F(000) = 1592
Mr = 1672.03Dx = 2.670 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 5569 reflections
a = 10.633 (2) Åθ = 2.1–27.5°
b = 11.552 (2) ŵ = 2.45 mm1
c = 17.240 (4) ÅT = 293 K
β = 101.553 (3)°Prism, colorless
V = 2074.7 (8) Å30.23 × 0.22 × 0.05 mm
Z = 2

Data collection

Siemens CCD area-detector diffractometer4534 independent reflections
Radiation source: fine-focus sealed tube4215 reflections with I > 2σ(I)
graphiteRint = 0.021
[var phi] and ω scansθmax = 27.5°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −13→13
Tmin = 0.829, Tmax = 1.000k = −13→14
14669 measured reflectionsl = −22→17

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)] = 0.022Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.098H-atom parameters constrained
S = 1.40w = 1/[σ2(Fo2) + (0.054P)2 + 0.4946P] where P = (Fo2 + 2Fc2)/3
4534 reflections(Δ/σ)max = 0.001
316 parametersΔρmax = 1.40 e Å3
0 restraintsΔρmin = −2.27 e Å3

Special details

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)

xyzUiso*/Ueq
Mo10.08119 (2)0.53770 (2)0.098624 (15)0.01481 (10)
Mo20.03951 (3)0.71904 (2)−0.069243 (16)0.01713 (10)
Mo30.25513 (2)0.49409 (2)−0.029720 (16)0.01602 (10)
Mo4−0.13294 (3)0.77083 (2)0.064661 (17)0.01917 (10)
O120.0104 (2)0.8099 (2)0.01704 (14)0.0218 (5)
O60.2011 (2)0.4893 (2)0.17096 (15)0.0252 (5)
O150.1779 (2)0.61483 (18)0.02814 (13)0.0168 (4)
O5−0.0636 (2)0.44017 (19)0.11312 (13)0.0165 (4)
O4−0.2513 (2)0.8238 (2)−0.00841 (16)0.0297 (6)
O70.3709 (2)0.4459 (2)0.04628 (15)0.0275 (5)
N20.5229 (3)0.1925 (2)1.09498 (17)0.0221 (6)
H2A0.51020.25871.07200.026*
O130.0261 (2)0.6628 (2)0.13799 (13)0.0205 (5)
C20.3935 (3)0.2606 (3)1.1832 (2)0.0259 (7)
H20.36750.32241.14910.031*
O110.3343 (2)0.5745 (2)−0.08718 (14)0.0242 (5)
O9−0.0852 (3)0.7563 (2)−0.14308 (15)0.0274 (5)
O100.1691 (3)0.7832 (2)−0.09476 (16)0.0273 (5)
C50.4718 (4)0.0833 (3)1.2863 (2)0.0301 (8)
H50.49850.02451.32270.036*
C40.5210 (4)0.0892 (3)1.2190 (2)0.0265 (7)
H40.58010.03461.20910.032*
N10.3858 (3)0.1609 (3)1.30054 (17)0.0280 (7)
H10.35450.15411.34260.034*
O3−0.1253 (3)0.8654 (2)0.14042 (16)0.0321 (6)
C30.4805 (3)0.1793 (3)1.16520 (18)0.0196 (6)
C10.3471 (4)0.2490 (3)1.2508 (2)0.0286 (8)
H1A0.28820.30251.26260.034*
O140.0844 (2)0.40727 (19)0.01120 (12)0.0173 (4)
O80.2273 (2)0.3590 (2)−0.09586 (13)0.0205 (5)
N30.8440 (3)0.0969 (3)0.75088 (17)0.0285 (7)
H30.87610.09880.70890.034*
O20.5624 (3)0.2419 (2)0.94778 (15)0.0289 (6)
O10.6119 (3)0.0145 (2)1.08260 (16)0.0334 (6)
N40.6865 (3)0.0776 (3)0.94989 (17)0.0236 (6)
H4A0.70650.01540.97700.028*
C110.7132 (3)0.1824 (3)0.8303 (2)0.0261 (7)
H110.66060.24280.83990.031*
C100.7680 (4)0.1841 (3)0.7648 (2)0.0298 (8)
H100.75250.24610.72970.036*
C80.8193 (4)0.0012 (3)0.8668 (2)0.0303 (8)
H80.8384−0.06090.90150.036*
C90.8712 (4)0.0072 (3)0.8005 (2)0.0333 (9)
H90.9256−0.05120.78980.040*
C120.7373 (3)0.0892 (3)0.88212 (18)0.0204 (6)
C60.5830 (3)0.1107 (3)1.05882 (19)0.0206 (6)
C70.6084 (3)0.1539 (3)0.97837 (19)0.0226 (7)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Mo10.01333 (15)0.02061 (16)0.01084 (15)−0.00116 (9)0.00325 (10)−0.00091 (10)
Mo20.01807 (16)0.01867 (16)0.01602 (16)0.00122 (10)0.00673 (11)0.00088 (10)
Mo30.01266 (15)0.02166 (17)0.01468 (16)0.00069 (9)0.00496 (11)0.00006 (10)
Mo40.01891 (17)0.02088 (16)0.01936 (16)0.00103 (10)0.00773 (12)−0.00038 (10)
O120.0232 (12)0.0214 (11)0.0228 (11)−0.0027 (9)0.0093 (10)−0.0038 (9)
O60.0216 (12)0.0342 (13)0.0184 (12)0.0020 (10)0.0003 (10)0.0029 (10)
O150.0156 (10)0.0194 (10)0.0160 (10)−0.0018 (8)0.0047 (8)−0.0007 (9)
O50.0162 (10)0.0199 (10)0.0146 (10)0.0006 (8)0.0057 (8)0.0005 (9)
O40.0250 (13)0.0339 (14)0.0311 (14)0.0052 (11)0.0073 (11)0.0089 (11)
O70.0216 (12)0.0381 (14)0.0221 (12)0.0048 (11)0.0026 (10)0.0052 (11)
N20.0260 (15)0.0251 (14)0.0176 (13)0.0021 (12)0.0105 (11)0.0042 (11)
O130.0204 (11)0.0226 (11)0.0192 (11)−0.0004 (9)0.0059 (9)−0.0040 (9)
C20.0268 (18)0.0300 (17)0.0226 (17)0.0055 (14)0.0089 (14)0.0044 (14)
O110.0217 (12)0.0292 (12)0.0237 (12)−0.0022 (10)0.0091 (10)0.0032 (10)
O90.0291 (13)0.0281 (12)0.0232 (12)0.0072 (11)0.0010 (11)0.0008 (11)
O100.0272 (13)0.0269 (13)0.0305 (13)−0.0026 (10)0.0127 (11)0.0019 (10)
C50.038 (2)0.0303 (18)0.0222 (17)0.0010 (16)0.0069 (15)0.0068 (15)
C40.0269 (18)0.0316 (18)0.0222 (17)0.0038 (14)0.0074 (14)0.0026 (15)
N10.0295 (16)0.0401 (17)0.0171 (13)−0.0029 (13)0.0114 (12)−0.0004 (13)
O30.0354 (14)0.0310 (13)0.0332 (14)0.0015 (11)0.0146 (12)−0.0097 (12)
C30.0180 (15)0.0268 (16)0.0148 (14)−0.0016 (12)0.0053 (12)0.0005 (13)
C10.0263 (18)0.0380 (19)0.0235 (17)0.0048 (15)0.0097 (15)−0.0007 (16)
O140.0169 (10)0.0209 (10)0.0153 (10)0.0003 (8)0.0063 (8)0.0001 (9)
O80.0223 (11)0.0228 (11)0.0193 (11)0.0002 (9)0.0110 (9)−0.0029 (9)
N30.0311 (16)0.0405 (17)0.0173 (13)−0.0040 (14)0.0130 (12)−0.0015 (13)
O20.0333 (14)0.0309 (13)0.0244 (13)0.0054 (11)0.0104 (11)0.0031 (11)
O10.0461 (17)0.0300 (14)0.0293 (14)0.0072 (12)0.0204 (13)0.0039 (11)
N40.0278 (15)0.0276 (14)0.0188 (13)0.0042 (12)0.0127 (12)0.0029 (12)
C110.0261 (17)0.0322 (18)0.0218 (16)0.0051 (14)0.0090 (14)0.0019 (14)
C100.0299 (19)0.040 (2)0.0209 (17)0.0027 (16)0.0074 (15)0.0061 (15)
C80.040 (2)0.0269 (18)0.0284 (19)0.0052 (15)0.0175 (17)0.0041 (15)
C90.042 (2)0.0317 (19)0.032 (2)−0.0007 (16)0.0210 (18)−0.0033 (16)
C120.0232 (16)0.0244 (16)0.0155 (14)−0.0036 (13)0.0081 (12)−0.0026 (12)
C60.0195 (15)0.0278 (16)0.0171 (14)−0.0042 (13)0.0094 (12)−0.0017 (13)
C70.0235 (16)0.0286 (16)0.0172 (15)−0.0049 (14)0.0076 (13)−0.0018 (14)

Geometric parameters (Å, °)

Mo1—O61.690 (2)C2—C31.395 (5)
Mo1—O131.747 (2)C2—H20.9300
Mo1—O151.956 (2)C5—N11.338 (5)
Mo1—O51.964 (2)C5—C41.366 (5)
Mo1—O142.136 (2)C5—H50.9300
Mo1—O14i2.399 (2)C4—C31.403 (5)
Mo1—Mo33.1951 (6)C4—H40.9300
Mo2—O101.699 (3)N1—C11.342 (5)
Mo2—O91.699 (3)N1—H10.8600
Mo2—O121.896 (2)C1—H1A0.9300
Mo2—O5i2.024 (2)O14—Mo2i2.322 (2)
Mo2—O14i2.322 (2)O14—Mo1i2.399 (2)
Mo2—O152.333 (2)O8—Mo4i1.939 (2)
Mo3—O111.699 (2)N3—C91.338 (5)
Mo3—O71.702 (2)N3—C101.342 (5)
Mo3—O81.921 (2)N3—H30.8600
Mo3—O151.986 (2)O2—C71.203 (4)
Mo3—O142.305 (2)O1—C61.203 (4)
Mo3—O5i2.370 (2)N4—C71.368 (4)
Mo4—O31.692 (3)N4—C121.388 (4)
Mo4—O41.706 (3)N4—H4A0.8600
Mo4—O121.924 (2)C11—C101.371 (5)
Mo4—O8i1.939 (2)C11—C121.390 (5)
Mo4—O132.271 (2)C11—H110.9300
O5—Mo2i2.024 (2)C10—H100.9300
O5—Mo3i2.370 (2)C8—C91.368 (5)
N2—C61.360 (4)C8—C121.398 (5)
N2—C31.383 (4)C8—H80.9300
N2—H2A0.8600C9—H90.9300
C2—C11.361 (5)C6—C71.548 (5)
O6—Mo1—O13104.42 (12)O12—Mo4—O1378.54 (10)
O6—Mo1—O15101.34 (11)O8i—Mo4—O1377.86 (9)
O13—Mo1—O1597.08 (10)Mo2—O12—Mo4118.21 (12)
O6—Mo1—O5102.18 (11)Mo1—O15—Mo3108.29 (10)
O13—Mo1—O595.32 (10)Mo1—O15—Mo2110.37 (10)
O15—Mo1—O5149.67 (9)Mo3—O15—Mo2105.41 (9)
O6—Mo1—O1499.85 (11)Mo1—O5—Mo2i108.21 (10)
O13—Mo1—O14155.72 (10)Mo1—O5—Mo3i109.83 (10)
O15—Mo1—O1478.37 (9)Mo2i—O5—Mo3i102.84 (9)
O5—Mo1—O1478.98 (9)C6—N2—C3126.2 (3)
O6—Mo1—O14i174.94 (10)C6—N2—H2A116.9
O13—Mo1—O14i80.62 (9)C3—N2—H2A116.9
O15—Mo1—O14i77.46 (8)Mo1—O13—Mo4120.57 (11)
O5—Mo1—O14i77.42 (8)C1—C2—C3119.6 (3)
O14—Mo1—O14i75.11 (9)C1—C2—H2120.2
O6—Mo1—Mo390.19 (9)C3—C2—H2120.2
O13—Mo1—Mo3133.25 (8)N1—C5—C4121.0 (3)
O15—Mo1—Mo336.17 (6)N1—C5—H5119.5
O5—Mo1—Mo3125.10 (6)C4—C5—H5119.5
O14—Mo1—Mo346.13 (6)C5—C4—C3118.6 (3)
O14i—Mo1—Mo386.01 (5)C5—C4—H4120.7
O10—Mo2—O9104.31 (13)C3—C4—H4120.7
O10—Mo2—O12103.29 (11)C5—N1—C1121.6 (3)
O9—Mo2—O12102.84 (11)C5—N1—H1119.2
O10—Mo2—O5i97.46 (11)C1—N1—H1119.2
O9—Mo2—O5i95.06 (11)N2—C3—C2117.9 (3)
O12—Mo2—O5i148.09 (10)N2—C3—C4123.3 (3)
O10—Mo2—O14i160.99 (11)C2—C3—C4118.8 (3)
O9—Mo2—O14i93.28 (11)N1—C1—C2120.3 (3)
O12—Mo2—O14i79.28 (9)N1—C1—H1A119.8
O5i—Mo2—O14i73.47 (8)C2—C1—H1A119.8
O10—Mo2—O1589.10 (11)Mo1—O14—Mo391.94 (8)
O9—Mo2—O15162.69 (11)Mo1—O14—Mo2i92.79 (8)
O12—Mo2—O1584.24 (9)Mo3—O14—Mo2i162.71 (11)
O5i—Mo2—O1572.02 (8)Mo1—O14—Mo1i104.89 (9)
O14i—Mo2—O1572.31 (8)Mo3—O14—Mo1i98.15 (8)
O11—Mo3—O7105.16 (12)Mo2i—O14—Mo1i96.69 (8)
O11—Mo3—O897.69 (11)Mo3—O8—Mo4i119.38 (11)
O7—Mo3—O8101.11 (12)C9—N3—C10121.9 (3)
O11—Mo3—O15102.23 (11)C9—N3—H3119.1
O7—Mo3—O1598.71 (11)C10—N3—H3119.1
O8—Mo3—O15147.03 (9)C7—N4—C12127.3 (3)
O11—Mo3—O14158.28 (10)C7—N4—H4A116.3
O7—Mo3—O1496.57 (11)C12—N4—H4A116.3
O8—Mo3—O1477.93 (9)C10—C11—C12119.1 (3)
O15—Mo3—O1473.83 (8)C10—C11—H11120.4
O11—Mo3—O5i86.39 (10)C12—C11—H11120.4
O7—Mo3—O5i166.64 (10)N3—C10—C11120.4 (3)
O8—Mo3—O5i83.62 (9)N3—C10—H10119.8
O15—Mo3—O5i71.82 (8)C11—C10—H10119.8
O14—Mo3—O5i72.03 (8)C9—C8—C12119.5 (3)
O11—Mo3—Mo1137.78 (9)C9—C8—H8120.3
O7—Mo3—Mo187.02 (9)C12—C8—H8120.3
O8—Mo3—Mo1119.84 (7)N3—C9—C8120.1 (4)
O15—Mo3—Mo135.55 (6)N3—C9—H9119.9
O14—Mo3—Mo141.93 (5)C8—C9—H9119.9
O5i—Mo3—Mo179.83 (5)N4—C12—C11124.3 (3)
O3—Mo4—O4104.63 (14)N4—C12—C8116.8 (3)
O3—Mo4—O12104.98 (12)C11—C12—C8118.9 (3)
O4—Mo4—O1297.54 (12)O1—C6—N2126.7 (3)
O3—Mo4—O8i103.44 (11)O1—C6—C7121.6 (3)
O4—Mo4—O8i97.81 (12)N2—C6—C7111.6 (3)
O12—Mo4—O8i142.92 (9)O2—C7—N4127.6 (3)
O3—Mo4—O1390.56 (11)O2—C7—C6122.5 (3)
O4—Mo4—O13164.80 (11)N4—C7—C6110.0 (3)

Symmetry codes: (i) −x, −y+1, −z.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N2—H2A···O7ii0.862.613.368 (4)148
N1—H1···O8iii0.861.892.699 (4)158
N3—H3···O5iv0.861.942.779 (4)165
N4—H4A···O10.862.252.669 (4)110
N4—H4A···O4v0.862.263.059 (4)154

Symmetry codes: (ii) x, y, z+1; (iii) x, −y+1/2, z+3/2; (iv) x+1, −y+1/2, z+1/2; (v) x+1, y−1, z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: SU2182).

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