Acta Cryst. (2007). E63, m1924 [ doi:10.1107/S1600536807027390 ]
In the title compound, poly[![[mu]](http://journals.iucr.org/logos/entities/mu_rmgif.gif)
2-2,3,5,6-tetra-2-pyridyl-1,4-dihydropyrazine--hexacosaoxidooctamolybdato-dicopper(II)], [Cu2Mo8O26(C24H16N6)], the organic linker 2,3,5,6-tetra-2-pyridyl-1,4-dihydropyrazine (tpyprz) brings together four [Mo8O26]4- clusters through the cationic bridge [Cu2(tpyprz)]4+ to from a two-dimensional layer. The copper(II) cation is five-coordinate in a distorted square-pyramidal configuration, bonding to three N atoms from the tpyprz ligand and two terminal O atoms from the molybdenum cluster. The [Mo8O26]4- cluster shows bonding only through the terminal O atoms attached to the octahedrally coordinated Mo atom along the central axis of the cluster.
Synthesis of [{Cu2(tpyprz)}Mo8O26] (1). A mixture of MoO3 (0.160 g, 1.11 mmol), Co(OCOCH3)2 (0.088 g, 0.441 mmol), tpypyz (0.086 g, 0.221 mmol), and H2O (10 g, 555 mmol) in the mole ratio 5.02:2.00:1.00:2511 was stirred briefly before heating to 453 K for 120 h. Light green plate like crystals of 1 were isolated in 45% yield: initial pH, 6; final pH, 3. IR (KBr pellet, cm-1): 3072(m, br), 2999(s), 1593(w), 1479(w), 1401(m), 1168(m), 1090(m), 1062(s), 952(s), 907(s), 739(s), 658(m).
H atoms were implemented geometrically using a riding constraint with a C—H fixed distance of 0.93 A and a Uiso of 1.2Ueq(C).
Data collection: SMART (Bruker, 2001); cell refinement: SMART; data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL (Sheldrick, 1997b) and CrystalMaker (CrystalMaker Software 2007); software used to prepare material for publication: SHELXTL.
![[Figure 1]](./br2040fig1thm.gif)
| Fig. 1. - ORTEP drawing of anionic molybdenum cluster [Mo8O26]4− and the cationic [Cu2(tpyprz)]4+ unit of the title compound (1), showing 50% probability displacement ellipsoids. H atoms omitted for clarity. |
![[Figure 2]](./br2040fig2thm.gif)
| Fig. 2. - Polyhedral representation of a single layer for compound 1. Cu atoms represented by dark blue polyhedra, Mo by green polyhedra, N by light blue, and C by black. H atoms ommitted for clarity. |
![[Figure 3]](./br2040fig3thm.gif)
| Fig. 3. - Polyhedral representation of three stacking layers of 1, forming a two-dimensional layer structure. |
| [Cu2Mo8O26(C24H16N6)] | Z = 2 |
| Mr = 849.51 | F000 = 804 |
| Triclinic, P1 | Dx = 2.851 Mg m−3 |
| Hall symbol: -P 1 | Mo Kα radiation λ = 0.71073 Å |
| a = 9.9920 (7) Å | Cell parameters from 4896 reflections |
| b = 10.0882 (7) Å | θ = 1.9–28.3º |
| c = 11.1708 (8) Å | µ = 3.60 mm−1 |
| α = 78.380 (8)º | T = 90 (2) K |
| β = 76.815 (9)º | Plate, green |
| γ = 65.419 (5)º | 0.24 × 0.16 × 0.14 mm |
| V = 989.75 (12) Å3 |
| Bruker APEX CCD detector diffractometer | 4896 independent reflections |
| Monochromator: graphite | 4307 reflections with I > 2σ(I) |
| Detector resolution: 512 pixels mm-1 | Rint = 0.025 |
| T = 90(2) K | θmax = 28.3º |
| φ and ω scans | θmin = 1.9º |
| Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −13→13 |
| Tmin = 0.479, Tmax = 0.633 | k = −13→13 |
| 10578 measured reflections | l = −14→14 |
| Refinement on F2 | Secondary atom site location: difference Fourier map |
| Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
| R[F2 > 2σ(F2)] = 0.027 | H-atom parameters constrained |
| wR(F2) = 0.062 | w = 1/[σ2(Fo2) + (0.0291P)2 + 2.178P] where P = (Fo2 + 2Fc2)/3 |
| S = 0.94 | (Δ/σ)max = 0.001 |
| 4896 reflections | Δρmax = 0.80 e Å−3 |
| 299 parameters | Δρmin = −0.89 e Å−3 |
| Primary atom site location: structure-invariant direct methods | Extinction correction: none |
| [Cu2Mo8O26(C24H16N6)] | γ = 65.419 (5)º |
| Mr = 849.51 | V = 989.75 (12) Å3 |
| Triclinic, P1 | Z = 2 |
| a = 9.9920 (7) Å | Mo Kα |
| b = 10.0882 (7) Å | µ = 3.60 mm−1 |
| c = 11.1708 (8) Å | T = 90 (2) K |
| α = 78.380 (8)º | 0.24 × 0.16 × 0.14 mm |
| β = 76.815 (9)º |
| Bruker APEX CCD detector diffractometer | 4896 independent reflections |
| Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 4307 reflections with I > 2σ(I) |
| Tmin = 0.479, Tmax = 0.633 | Rint = 0.025 |
| 10578 measured reflections |
| R[F2 > 2σ(F2)] = 0.027 | 299 parameters |
| wR(F2) = 0.062 | H-atom parameters constrained |
| S = 0.94 | Δρmax = 0.80 e Å−3 |
| 4896 reflections | Δρmin = −0.89 e Å−3 |
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 > 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. |
| x | y | z | Uiso*/Ueq | ||
| Mo1 | 0.77935 (3) | 0.61288 (3) | 0.79284 (3) | 0.01016 (7) | |
| Mo2 | 0.88214 (3) | 0.41297 (3) | 0.55817 (3) | 0.00797 (7) | |
| Mo3 | 0.73644 (3) | 0.77007 (3) | 0.46269 (3) | 0.00746 (7) | |
| Mo4 | 0.92292 (3) | 0.68237 (3) | 0.17919 (3) | 0.01363 (8) | |
| Cu1 | 0.36121 (4) | 0.82861 (5) | 0.45710 (4) | 0.00889 (9) | |
| O1 | 0.6347 (3) | 0.5844 (3) | 0.8909 (2) | 0.0187 (6) | |
| O2 | 0.7496 (4) | 0.7901 (3) | 0.7984 (3) | 0.0280 (7) | |
| O3 | 0.9513 (3) | 0.5148 (3) | 0.8652 (2) | 0.0153 (5) | |
| O4 | 0.8896 (3) | 0.3842 (3) | 0.7297 (2) | 0.0101 (5) | |
| O5 | 0.7276 (3) | 0.3837 (3) | 0.5533 (2) | 0.0126 (5) | |
| O6 | 0.7559 (3) | 0.6323 (2) | 0.6213 (2) | 0.0094 (5) | |
| O7 | 1.0337 (3) | 0.2564 (3) | 0.5070 (2) | 0.0104 (5) | |
| O8 | 0.8961 (3) | 0.5515 (3) | 0.4189 (2) | 0.0104 (5) | |
| O9 | 0.6673 (3) | 0.9306 (3) | 0.5254 (2) | 0.0121 (5) | |
| O10 | 0.5772 (3) | 0.7536 (3) | 0.4371 (2) | 0.0103 (5) | |
| O11 | 0.8197 (3) | 0.8207 (3) | 0.3041 (2) | 0.0103 (5) | |
| O13 | 0.9652 (3) | 0.7952 (3) | 0.0572 (3) | 0.0260 (7) | |
| N1 | 0.3303 (3) | 0.8814 (3) | 0.2808 (3) | 0.0100 (6) | |
| N2 | 0.1442 (3) | 0.9181 (3) | 0.4810 (3) | 0.0076 (5) | |
| N3 | 0.3167 (3) | 0.7618 (3) | 0.6371 (3) | 0.0097 (6) | |
| C1 | 0.4353 (4) | 0.8375 (4) | 0.1833 (3) | 0.0169 (8) | |
| H1 | 0.5349 | 0.7982 | 0.1935 | 0.020* | |
| C2 | 0.4015 (5) | 0.8481 (5) | 0.0670 (4) | 0.0230 (9) | |
| H2 | 0.4770 | 0.8196 | −0.0004 | 0.028* | |
| C3 | 0.2537 (5) | 0.9018 (4) | 0.0535 (4) | 0.0203 (8) | |
| H3 | 0.2283 | 0.9048 | −0.0224 | 0.024* | |
| C4 | 0.1424 (4) | 0.9517 (4) | 0.1543 (3) | 0.0133 (7) | |
| H4 | 0.0421 | 0.9893 | 0.1466 | 0.016* | |
| C5 | 0.1848 (4) | 0.9439 (3) | 0.2650 (3) | 0.0095 (6) | |
| C6 | 0.0799 (4) | 0.9875 (4) | 0.3812 (3) | 0.0086 (6) | |
| C7 | 0.0729 (4) | 0.9208 (4) | 0.5985 (3) | 0.0086 (6) | |
| C8 | 0.1688 (4) | 0.8103 (4) | 0.6846 (3) | 0.0094 (6) | |
| C9 | 0.1152 (4) | 0.7432 (4) | 0.7943 (3) | 0.0109 (7) | |
| H9 | 0.0135 | 0.7757 | 0.8244 | 0.013* | |
| C10 | 0.2172 (4) | 0.6257 (4) | 0.8587 (3) | 0.0130 (7) | |
| H10 | 0.1839 | 0.5787 | 0.9325 | 0.016* | |
| C11 | 0.3657 (4) | 0.5803 (4) | 0.8129 (3) | 0.0151 (7) | |
| H11 | 0.4349 | 0.5037 | 0.8560 | 0.018* | |
| C12 | 0.4123 (4) | 0.6499 (4) | 0.7008 (3) | 0.0139 (7) | |
| H12 | 0.5136 | 0.6175 | 0.6690 | 0.017* | |
| O12 | 0.7658 (3) | 0.6700 (4) | 0.1582 (3) | 0.0368 (9) |
| U11 | U22 | U33 | U12 | U13 | U23 | |
| Mo1 | 0.01090 (15) | 0.01001 (14) | 0.00936 (14) | −0.00350 (11) | −0.00285 (11) | −0.00054 (11) |
| Mo2 | 0.00654 (14) | 0.00650 (13) | 0.01088 (14) | −0.00218 (11) | −0.00178 (11) | −0.00146 (10) |
| Mo3 | 0.00551 (13) | 0.00683 (13) | 0.00904 (14) | −0.00141 (11) | −0.00132 (10) | −0.00081 (10) |
| Mo4 | 0.00738 (14) | 0.01504 (16) | 0.01633 (16) | −0.00004 (12) | −0.00278 (12) | −0.00587 (12) |
| Cu1 | 0.00514 (19) | 0.0108 (2) | 0.0090 (2) | −0.00178 (16) | −0.00113 (16) | −0.00028 (15) |
| O1 | 0.0112 (13) | 0.0305 (16) | 0.0132 (13) | −0.0066 (11) | −0.0002 (10) | −0.0051 (11) |
| O2 | 0.048 (2) | 0.0129 (14) | 0.0300 (17) | −0.0112 (13) | −0.0254 (15) | 0.0020 (12) |
| O3 | 0.0087 (12) | 0.0176 (13) | 0.0192 (14) | −0.0011 (10) | −0.0030 (10) | −0.0093 (11) |
| O4 | 0.0099 (12) | 0.0106 (12) | 0.0093 (12) | −0.0034 (9) | −0.0017 (9) | −0.0006 (9) |
| O5 | 0.0097 (12) | 0.0122 (12) | 0.0155 (13) | −0.0035 (10) | −0.0032 (10) | −0.0016 (10) |
| O6 | 0.0093 (12) | 0.0081 (11) | 0.0089 (11) | −0.0020 (9) | −0.0020 (9) | 0.0005 (9) |
| O7 | 0.0079 (11) | 0.0087 (11) | 0.0148 (12) | −0.0033 (9) | −0.0012 (10) | −0.0024 (9) |
| O8 | 0.0079 (11) | 0.0094 (11) | 0.0132 (12) | −0.0023 (9) | −0.0023 (10) | −0.0013 (9) |
| O9 | 0.0107 (12) | 0.0090 (12) | 0.0158 (13) | −0.0024 (10) | −0.0026 (10) | −0.0020 (10) |
| O10 | 0.0079 (11) | 0.0113 (12) | 0.0113 (12) | −0.0035 (9) | −0.0029 (9) | 0.0007 (9) |
| O11 | 0.0088 (12) | 0.0073 (11) | 0.0115 (12) | −0.0014 (9) | −0.0004 (10) | 0.0008 (9) |
| O13 | 0.0285 (16) | 0.0223 (15) | 0.0112 (13) | 0.0046 (12) | −0.0027 (12) | −0.0002 (11) |
| N1 | 0.0091 (14) | 0.0087 (14) | 0.0108 (14) | −0.0026 (11) | −0.0004 (11) | −0.0009 (11) |
| N2 | 0.0065 (13) | 0.0065 (13) | 0.0116 (14) | −0.0043 (10) | −0.0011 (11) | −0.0012 (11) |
| N3 | 0.0094 (14) | 0.0112 (14) | 0.0090 (14) | −0.0049 (11) | −0.0017 (11) | −0.0002 (11) |
| C1 | 0.0086 (17) | 0.0187 (19) | 0.0147 (18) | 0.0018 (14) | 0.0006 (14) | −0.0014 (15) |
| C2 | 0.016 (2) | 0.026 (2) | 0.0154 (19) | 0.0017 (16) | 0.0005 (16) | −0.0039 (16) |
| C3 | 0.024 (2) | 0.021 (2) | 0.0107 (18) | −0.0005 (16) | −0.0056 (16) | −0.0048 (15) |
| C4 | 0.0117 (17) | 0.0105 (16) | 0.0159 (18) | −0.0015 (13) | −0.0046 (14) | −0.0010 (13) |
| C5 | 0.0085 (16) | 0.0043 (14) | 0.0133 (17) | −0.0010 (12) | −0.0013 (13) | 0.0005 (12) |
| C6 | 0.0070 (15) | 0.0086 (15) | 0.0106 (16) | −0.0031 (12) | −0.0019 (13) | −0.0009 (12) |
| C7 | 0.0089 (16) | 0.0072 (15) | 0.0131 (16) | −0.0054 (13) | −0.0039 (13) | −0.0015 (12) |
| C8 | 0.0073 (16) | 0.0109 (16) | 0.0122 (16) | −0.0048 (13) | −0.0026 (13) | −0.0023 (13) |
| C9 | 0.0091 (16) | 0.0122 (16) | 0.0111 (16) | −0.0040 (13) | −0.0014 (13) | −0.0017 (13) |
| C10 | 0.0144 (18) | 0.0127 (17) | 0.0118 (17) | −0.0049 (14) | −0.0032 (14) | −0.0008 (13) |
| C11 | 0.0138 (18) | 0.0121 (17) | 0.0169 (18) | −0.0028 (14) | −0.0069 (15) | 0.0040 (14) |
| C12 | 0.0061 (16) | 0.0132 (17) | 0.0211 (19) | −0.0027 (13) | −0.0035 (14) | 0.0003 (14) |
| O12 | 0.0107 (14) | 0.0404 (19) | 0.063 (2) | 0.0013 (13) | −0.0092 (15) | −0.0364 (18) |
| Mo1—O1 | 1.694 (3) | Cu1—N3 | 1.998 (3) |
| Mo1—O2 | 1.698 (3) | Cu1—O9ii | 2.368 (2) |
| Mo1—O3 | 1.866 (3) | O3—Mo4i | 1.954 (3) |
| Mo1—O6 | 1.944 (2) | O4—Mo4i | 2.132 (2) |
| Mo1—O4 | 2.285 (2) | O7—Mo3i | 2.296 (2) |
| Mo2—O5 | 1.703 (2) | O8—Mo2i | 2.462 (2) |
| Mo2—O7 | 1.759 (2) | O9—Cu1ii | 2.368 (2) |
| Mo2—O8 | 1.892 (2) | N1—C1 | 1.330 (5) |
| Mo2—O4 | 1.893 (2) | N1—C5 | 1.361 (4) |
| Mo2—O6 | 2.210 (2) | N2—C6 | 1.335 (4) |
| Mo2—O8i | 2.462 (2) | N2—C7 | 1.343 (4) |
| Mo3—O9 | 1.702 (2) | N3—C12 | 1.335 (4) |
| Mo3—O10 | 1.757 (2) | N3—C8 | 1.360 (4) |
| Mo3—O11 | 1.846 (2) | C1—C2 | 1.389 (5) |
| Mo3—O6 | 2.012 (2) | C2—C3 | 1.379 (6) |
| Mo3—O8 | 2.190 (2) | C3—C4 | 1.396 (5) |
| Mo3—O7i | 2.296 (2) | C4—C5 | 1.374 (5) |
| Mo4—O13 | 1.686 (3) | C5—C6 | 1.485 (5) |
| Mo4—O12 | 1.696 (3) | C6—C7iii | 1.411 (5) |
| Mo4—O3i | 1.954 (3) | C7—C6iii | 1.411 (5) |
| Mo4—O11 | 1.972 (2) | C7—C8 | 1.478 (5) |
| Mo4—O4i | 2.132 (2) | C8—C9 | 1.384 (5) |
| Cu1—O10 | 1.942 (2) | C9—C10 | 1.395 (5) |
| Cu1—N2 | 1.948 (3) | C10—C11 | 1.363 (5) |
| Cu1—N1 | 1.994 (3) | C11—C12 | 1.389 (5) |
| O1—Mo1—O2 | 105.33 (15) | N2—Cu1—N1 | 80.29 (12) |
| O1—Mo1—O3 | 108.95 (12) | O10—Cu1—N3 | 99.31 (11) |
| O2—Mo1—O3 | 100.57 (13) | N2—Cu1—N3 | 80.51 (12) |
| O1—Mo1—O6 | 110.97 (11) | N1—Cu1—N3 | 156.47 (12) |
| O2—Mo1—O6 | 97.97 (12) | O10—Cu1—O9ii | 93.15 (9) |
| O3—Mo1—O6 | 129.13 (11) | N2—Cu1—O9ii | 82.34 (10) |
| O1—Mo1—O4 | 96.02 (11) | N1—Cu1—O9ii | 92.50 (10) |
| O2—Mo1—O4 | 158.56 (13) | N3—Cu1—O9ii | 98.29 (10) |
| O3—Mo1—O4 | 73.73 (10) | Mo1—O3—Mo4i | 116.04 (13) |
| O6—Mo1—O4 | 71.98 (9) | Mo2—O4—Mo4i | 129.26 (12) |
| O5—Mo2—O7 | 105.04 (11) | Mo2—O4—Mo1 | 105.88 (10) |
| O5—Mo2—O8 | 105.02 (11) | Mo4i—O4—Mo1 | 94.31 (9) |
| O7—Mo2—O8 | 99.35 (11) | Mo1—O6—Mo3 | 143.27 (13) |
| O5—Mo2—O4 | 103.33 (11) | Mo1—O6—Mo2 | 106.96 (10) |
| O7—Mo2—O4 | 101.78 (11) | Mo3—O6—Mo2 | 103.63 (10) |
| O8—Mo2—O4 | 138.54 (10) | Mo2—O7—Mo3i | 115.98 (12) |
| O5—Mo2—O6 | 94.74 (10) | Mo2—O8—Mo3 | 108.69 (11) |
| O7—Mo2—O6 | 160.16 (10) | Mo2—O8—Mo2i | 101.18 (10) |
| O8—Mo2—O6 | 73.47 (9) | Mo3—O8—Mo2i | 95.55 (9) |
| O4—Mo2—O6 | 74.62 (9) | Mo3—O9—Cu1ii | 156.88 (14) |
| O5—Mo2—O8i | 175.91 (10) | Mo3—O10—Cu1 | 148.28 (15) |
| O7—Mo2—O8i | 75.43 (9) | Mo3—O11—Mo4 | 123.85 (12) |
| O8—Mo2—O8i | 78.82 (10) | C1—N1—C5 | 118.8 (3) |
| O4—Mo2—O8i | 72.65 (9) | C1—N1—Cu1 | 125.4 (2) |
| O6—Mo2—O8i | 84.96 (8) | C5—N1—Cu1 | 114.5 (2) |
| O9—Mo3—O10 | 103.92 (12) | C6—N2—C7 | 125.2 (3) |
| O9—Mo3—O11 | 102.31 (11) | C6—N2—Cu1 | 117.5 (2) |
| O10—Mo3—O11 | 102.10 (11) | C7—N2—Cu1 | 116.7 (2) |
| O9—Mo3—O6 | 98.04 (11) | C12—N3—C8 | 118.8 (3) |
| O10—Mo3—O6 | 95.09 (10) | C12—N3—Cu1 | 124.7 (2) |
| O11—Mo3—O6 | 149.19 (10) | C8—N3—Cu1 | 114.2 (2) |
| O9—Mo3—O8 | 157.58 (11) | N1—C1—C2 | 122.3 (3) |
| O10—Mo3—O8 | 96.96 (10) | C3—C2—C1 | 118.5 (4) |
| O11—Mo3—O8 | 80.86 (10) | C2—C3—C4 | 119.7 (4) |
| O6—Mo3—O8 | 71.74 (9) | C5—C4—C3 | 118.3 (3) |
| O9—Mo3—O7i | 86.65 (10) | N1—C5—C4 | 122.1 (3) |
| O10—Mo3—O7i | 168.87 (10) | N1—C5—C6 | 113.1 (3) |
| O11—Mo3—O7i | 78.61 (10) | C4—C5—C6 | 124.6 (3) |
| O6—Mo3—O7i | 79.76 (9) | N2—C6—C7iii | 117.3 (3) |
| O8—Mo3—O7i | 72.10 (9) | N2—C6—C5 | 111.5 (3) |
| O13—Mo4—O12 | 106.36 (17) | C7iii—C6—C5 | 131.0 (3) |
| O13—Mo4—O3i | 104.35 (13) | N2—C7—C6iii | 117.3 (3) |
| O12—Mo4—O3i | 92.74 (13) | N2—C7—C8 | 111.7 (3) |
| O13—Mo4—O11 | 100.43 (12) | C6iii—C7—C8 | 130.6 (3) |
| O12—Mo4—O11 | 94.88 (12) | N3—C8—C9 | 121.6 (3) |
| O3i—Mo4—O11 | 150.80 (10) | N3—C8—C7 | 113.6 (3) |
| O13—Mo4—O4i | 100.53 (13) | C9—C8—C7 | 124.0 (3) |
| O12—Mo4—O4i | 152.68 (15) | C8—C9—C10 | 118.5 (3) |
| O3i—Mo4—O4i | 75.76 (10) | C11—C10—C9 | 119.7 (3) |
| O11—Mo4—O4i | 84.80 (10) | C10—C11—C12 | 119.1 (3) |
| O10—Cu1—N2 | 175.40 (11) | N3—C12—C11 | 122.3 (3) |
| O10—Cu1—N1 | 100.91 (11) |
| Symmetry codes: (i) −x+2, −y+1, −z+1; (ii) −x+1, −y+2, −z+1; (iii) −x, −y+2, −z+1. |
This work was supported by a grant from the National Science Foundation (CHE-0604527).
Bruker (2001). SMART (Version 5.624). Bruker AXS, Inc., Madison, Wisconsin, USA.
Bruker (2003). SAINT-Plus (Version 6.25). Bruker AXS, Inc., Madison, Wisconsin, USA.
Buchner, W., Schiebs, R., Winter, G. & Buchel, K. H. (1989). Industrial Inorganic Chemistry. New York: VCH. Not in text?
Burkholder, E., Golub, V., O'Connor, C. J. & Zubieta, J. (2003). Inorg. Chem. 42, 6729–6740. Not in text?
Cheetham, A. K. (1994). Science, 264, 794–795. Not in text?
Cockayne, B. & Jones, D. W. (1972). In Modern Oxide Materials, edited by D. W. Jones. New York: Academic Press.
CrystalMaker Software (2007). CrystalMaker. Version 6.X. CrystalMaker Software Ltd, Oxfordshire, England.
Ferey, G. J. (2000). J. Solid State Chem. 152, 37–48.
Greenwood, N. N. & Earnshaw, A. (1984). Chemistry of the Elements. New York: Pergamon Press.
Hagrman, P. J., Hagrman, D. & Zubieta, J. (1999). Angew. Chem. Int. Ed. Engl. 38, 2639–2684. Not in text?
Johnson, B. J. S., Schroden, R. C., Zhu, C. & Stein, A. (2001). Inorg. Chem. 40, 5972–5978. Not in text?
Palmer, D. (2005). CrystalMaker. Version 7.1. CrystalMaker Software Ltd, Yarnton, Oxfordshire, England. Not in text?
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.
Sheldrick, G. M. (1997a). SHELXS97 and SHELXL97. University of Göttingen, Germany.
Sheldrick, G. M. (1997b). SHELXTL (Version 5.10). Bruker AXS Inc., Madison, Wisconsin, USA.
Zaworotko, M. J. (2000). Angew. Chem. Int. Ed. Engl. 39, 3052–3054. Not in text?
Zubieta, J. & Rarig, R. (2002). J. Solid State Chem. 167 (2), 370–375.
Organic–inorganic hybrid materials represent an expanding class of materials characterized by broad compositional range and structural versatility (Greenwood & Earnshaw, 1984). Inorganic oxides possess properties that are useful in the design of materials including but not limited to optical, electronic, magnetic, and mechanical. However, rational synthesis of these materials still remains an elusive goal (Cockayne & Jones, 1972). The molecular building block approach is an established method for synthesis of these materials (Ferey, 2000).
In an ongoing research investigation of such hybrid materials compound 1, [{Cu2(tpyprz)}Mo8O26] was synthesized under mild hydrothermal conditions. This synthetic approach favors the formation of the {Mo5O15(RPO3)2}4− clusters; however, in this reaction the phosphonate does not incorporate, leaving only a molybdenum oxide cluster to act as the oxide building block. The ligand of choice, tetra-2-pyridylpyrazine (tpyprz), along with the appropriate transition metal, act as a bridge between two or more of these molybdenum clusters.
Compound 1 is a two-dimensional layer formed from {Mo8O26}4− clusters and {Cu2(tpyprz)}4+ bridging cationic units. The copper-tpyprz moiety is attached to four different molybdenum clusters creating stacked sheets of this continuous layer. Copper is five coordinate in a distorted square pyramidal configuration, bonding to three N atoms from one side of the tpyprz ligand and two terminal O atoms from the molybdenum cluster. A weak bond exsits between copper and the axial oxygen, Cu—O9 at 2.37 A, provides a good valence bond sum for the copper cation. The terminal O atoms on the molybdenum cluster, O9 and O10, are responsible for the expansion of the structure. The equatorial oxygen, O10, extends the structure into a one-dimensional chain. The axial oxygen, O9, lies perpendicular to the chain, connecting adjacent chains. It is interesting to note that O9 aligns above the tpyprz plane on one side and below on the other side; this alternating up-down positioning allows the expansion of the structure into a layer.