One-dimensional chains consisting of copper(II) ions and an orthogonal anthracene-pyrimidine derivative: hierarchical formation of high-dimensional networks and their magnetic properties
作者:Takayoshi Ezuhara、Ken Endo、Kenji Matsuda、Yasuhiro Aoyama
DOI:10.1039/b002315i
日期:——
Recrystallization
of 9-(5-pyrimidinyl)anthracene (1) with copper(II) nitrate trihydrate formed three
kinds of complexes: 1·Cu(NO3)2·H2O (2), 1·Cu(NO3)2·MeOH·H2O (3) and 1·Cu(NO3)2·2EtOH (4) by changing the recrystallization solvent. The crystal structure of the three complexes showed cooperation of metal coordination,
hydrogen bonding, and aromatic stacking interactions in the hierarchical formation of one-, two- and three-dimensional networks. Complexes 2 and 3 formed zigzag one-dimensional chains consisting of 1 and Cu2+ ions by
coordination of pyrimidine to Cu2+ ion in equatorial trans fashion. Complex 4 formed a spiral one-dimensional chain by coordination in equatorial cis fashion. The magnetic behavior of 2, 3, and 4 were measured on a SQUID
susceptometer to reveal that there existed strong antiferromagnetic interactions between Cu2+ ions. The
magnetic data of one-dimensional antiferromagnetic chains were analyzed by the Bonner–Fisher model. The antiferromagnetic
interaction between Cu2+
ions was around
−55 K,
which is the largest value observed in pyrimidine-bridged Cu2+
ions.
再结晶
9-(5-嘧啶基)蒽(1)与三水合硝酸铜(II)生成三
通过改变重结晶溶剂,得到了多种配合物:1·Cu(NO3)2·H2O (2)、1·Cu(NO3)2·MeOH·H2O (3)和1·Cu(NO3)2·2EtOH (4)。三种配合物的晶体结构表现出金属配位的协同作用,
一维、二维和三维网络的分层形成中的氢键和芳香族堆积相互作用。配合物 2 和 3 形成由 1 和 Cu2+ 离子组成的锯齿形一维链
嘧啶与 Cu2+ 离子以赤道反式方式配位。配合物4以赤道顺式配位形成螺旋状一维链。 2、3 和 4 的磁性行为是在 SQUID 上测量的
磁化率计揭示了Cu2+离子之间存在强烈的反铁磁相互作用。这
通过 Bonner-Fisher 模型分析一维反铁磁链的磁数据。反铁磁性
Cu2+之间的相互作用
离子在周围
−55 K,
这是在嘧啶桥连的 Cu2+ 中观察到的最大值
离子。