Tandon Santokh Singh, Bunge Scott D, Motry Douglas, Costa José Sánchez, Aromí Guillem, Reedijk Jan, Thompson Laurence K
Department of Chemistry, Kent State University at Salem, Salem, Ohio 44460, USA.
Inorg Chem. 2009 Jun 1;48(11):4873-81. doi: 10.1021/ic900240y.
Reactions between the potentially pentadentate (N(2)O(3)), trianionic double Schiff-base ligand 2,6-bis[[(2-hydroxyethyl)imino]methyl]-4-methylphenol (H(3)L) and Cu(CH(3)CO(2))(2) or Cu(ClO(4))(2), in the presence of NaN(3), give novel coordination polymers with chain {Cu(2)(H(2)L)(N(3))(3).H(2)O}(n) (1) or sheet Cu(2)(H(2)L)(N(3))(3) (2) and Cu(2)(HL)(N(3))ClO(4) (3) structures, respectively. These clusters are comprised of repeating dinuclear units (1) or their dimers (2 and 3). In these compounds, H(3)L acts as a tridentate (N(2)O) monoanionic (1), tetradentate (ON(2)O) monoanionic (2), or pentadentate (O(3)N(2)) dianionic (3) ligand. Compound [Cu(2)(HL)(N(3))(2)(H(2)O)].0.5CH(3)OH (4) formed from the reaction of Cu(CH(3)CO(2))(2) with H(3)L under reflux, which did not afford crystals suitable for X-ray studies. X-ray structure determinations have revealed that the basic building block in 1-3 comprises two copper centers bridged through one mu-phenolate O atom from H(2)L(-) or HL(2-) and one mu-azido(N1,N1) ion. Compounds 1-3 unveil three different ways in which this Cu(2) basic unit may be organized in the crystalline phase at the supramolecular level through a variety of bridging interactions involving additional azide ligands or alkoxide groups from the side arms of the ligand H(3)L. Bulk magnetization measurements have served to demonstrate that the magnetic interactions are completely dominated by the strong antiferromagnetic coupling occurring within the Cu(2) building block, with coupling constants ranging from 330 to 560 cm(-1) (in the H = -JS(1)S(2) convention). These results together have been incorporated with data from the few related copper dimers reported exhibiting the same bridging pattern into a study aimed at extracting possible magnetostructural correlations within this Cu(2) unit. An earlier predicted correlation between J and the angle formed by the phenoxide bridge and the Cu(2) core has been identified for the first time.
在叠氮化钠存在的情况下，潜在的五齿（N(2)O(3)）三阴离子双席夫碱配体2,6 - 双[[(2 - 羟乙基)亚氨基]甲基]-4 - 甲基苯酚（H(3)L）与醋酸铜（Cu(CH(3)CO(2))(2)）或高氯酸铜（Cu(ClO(4))(2)）反应，分别生成具有链状{Cu(2)(H(2)L)(N(3))(3).H(2)O}(n)（1）、片状Cu(2)(H(2)L)(N(3))(3)（2）和Cu(2)(HL)(N(3))ClO(4)（3）结构的新型配位聚合物。这些簇由重复的双核单元（1）或其 dimer（2和3）组成。在这些化合物中，H(3)L分别作为三齿（N(2)O）单阴离子（1）、四齿（ON(2)O）单阴离子（2）或五齿（O(3)N(2)）双阴离子（3）配体。由醋酸铜（Cu(CH(3)CO(2))(2)）与H(3)L在回流条件下反应形成的化合物[Cu(2)(HL)(N(3))(2)(H(2)O)].0.5CH(3)OH（4），未得到适合X射线研究的晶体。X射线结构测定表明，1 - 3中的基本结构单元由两个铜中心组成，通过来自H(2)L(-)或HL(2 -)的一个μ - 酚氧基O原子和一个μ - 叠氮基（N1,N1）离子桥连。化合物1 - 3揭示了这种Cu(2)基本单元在超分子水平上在晶相中通过涉及来自配体H(3)L侧链的额外叠氮配体或醇盐基团的各种桥连相互作用而组织的三种不同方式。体磁化率测量表明，磁相互作用完全由Cu(2)结构单元内发生的强反铁磁耦合主导，耦合常数范围为330至560 cm(-1)（在H = -JS(1)S(2)约定中）。这些结果与少数报道的具有相同桥连模式的相关铜二聚体的数据一起，纳入了一项旨在提取该Cu(2)单元内可能的磁结构相关性的研究中。首次确定了先前预测的J与酚氧基桥和Cu(2)核心形成的角度之间的相关性。
