Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel, D-24118 Kiel, Germany.
Inorg Chem. 2012 Feb 20;51(4):2311-7. doi: 10.1021/ic2023117. Epub 2012 Jan 10.
Two new polyoxovanadates (Co(N(3)C(5)H(15))(2))(2)[{Co(N(3)C(5)H(15))(2)}V(15)Sb(6)O(42)(H(2)O)]·5H(2)O (1) and (Ni(N(3)C(5)H(15))(2))(2)[{Ni(N(3)C(5)H(15))(2)}V(15)Sb(6)O(42)(H(2)O)]·8H(2)O (2) (N(3)C(5)H(15) = N-(2-aminoethyl)-1,3-propanediamine) were synthesized under solvothermal conditions and structurally characterized. In both structures the V(15)Sb(6)O(42)(H(2)O) shell displays the main structural motif, which is strongly related to the {V(18)O(42)} archetype cluster. Both compounds crystallize in the triclinic space group P1 with a = 14.3438(4), b = 16.6471(6), c = 18.9186(6) Å, α = 87.291(3)°, β = 83.340(3)°, γ = 78.890(3)°, and V = 4401.4(2) Å(3) (1) and a = 14.5697(13), b = 15.8523(16), c = 20.2411(18) Å, α = 86.702(11)°, β = 84.957(11)°, γ = 76.941(11)°, and V = 4533.0(7) Å(3) (2). In the structure of 1 the V(15)Sb(6)O(42)(H(2)O) cluster anion is bound to a Co(N(3)C(5)H(15))(2) complex via a terminal oxygen atom. In the Co(2+)-centered complex, one of the amine ligands coordinates in tridentate mode and the second one in bidentate mode to form a strongly distorted CoN(5)O octahedron. Similarly, in compound 2 an analogous NiN(5)O complex is joined to the V(15)Sb(6)O(42)(H(2)O) anion via the same attachment mode. A remarkable difference between the two compounds is the orientation of the noncoordinated propylamine group leading to intermolecular Sb···O contacts in 1 and to Sb···N interactions in 2. In the solid-state lattices of 1 and 2, two additional M(N(3)C(5)H(15))(2) complexes act as countercations and are located between the {M(N(3)C(5)H(15))(2)}V(15)Sb(6)O(42)(H(2)O) anions. Between the anions and cations strong N-H···O hydrogen bonds are observed. In both compounds the clusters are stacked along the b axis in an ABAB fashion with cations and water molecules occupying the space between the clusters. Magnetic characterization demonstrates that the Ni(2+) and Co(2+) cations do not significantly couple with the S = 1/2 vanadyl groups. The susceptibility data can be successfully reproduced assuming a distorted ligand field for the Co(2+) ions (1) and an O(h)-symmetric Ni(2+) ligand field (2).
两种新型的多钒酸盐（Co（N（3）C（5）H（15））（2））（2）[{Co（N（3）C（5）H（15））（2）}V（15）Sb（6）O（42）（H（2）O）]·5H（2）O（1）和（Ni（N（3）C（5）H（15））（2））（2）[{Ni（N（3）C（5）H（15））（2）}V（15）Sb（6）O（42）（H（2）O）]·8H（2）O（2）（N（3）C（5）H（15）= N-（2-氨基乙基）-1,3-丙二胺）在溶剂热条件下合成并进行了结构表征。在这两个结构中，[V（15）Sb（6）O（42）（H（2）O）]（6-）壳层显示出主要的结构主题，这与{V（18）O（42）}原型簇强烈相关。两种化合物均结晶在三斜空间群 P1 中，a = 14.3438（4），b = 16.6471（6），c = 18.9186（6）Å，α= 87.291（3）°，β= 83.340（3）°，γ= 78.890（3）°，V = 4401.4（2）Å（3）（1）和 a = 14.5697（13），b = 15.8523（16），c = 20.2411（18）Å，α= 86.702（11）°，β= 84.957（11）°，γ= 76.941（11）°，V = 4533.0（7）Å（3）（2）。在 1 的结构中，[V（15）Sb（6）O（42）（H（2）O）]（6-）簇阴离子通过末端氧原子与[Co（N（3）C（5）H（15））（2）]（2+）配合物结合。在 Co（2+）中心配合物中，一个胺配体以三齿配位模式配位，另一个以双齿配位模式配位，形成强烈扭曲的 CoN（5）O 八面体。类似地，在化合物 2 中，类似的 NiN（5）O 配合物通过相同的连接模式与[V（15）Sb（6）O（42）（H（2）O）]（6-）阴离子结合。这两种化合物之间的一个显著区别是未配位的丙基胺基团的取向，导致在 1 中存在 Sb···O 接触，而在 2 中存在 Sb···N 相互作用。在 1 和 2 的固体晶格中，另外两个[M（N（3）C（5）H（15））（2）]（2+）配合物作为抗衡阳离子存在，位于[{M（N（3）C（5）H（15））（2）}V（15）Sb（6）O（42）（H（2）O）]（4-）阴离子之间。在阴离子和阳离子之间观察到强烈的 N-H···O 氢键。在这两种化合物中，簇沿 b 轴以 ABAB 方式堆积，阳离子和水分子占据簇之间的空间。磁性表征表明，Ni（2+）和 Co（2+）阳离子与 S = 1/2 钒氧基基团没有显著耦合。磁化率数据可以通过假设 Co（2+）离子的扭曲配体场（1）和 O（h）对称的 Ni（2+）配体场（2）来成功再现。
