Contrasting crystal supramolecularity for [Fe(phen)3]I8 and [Mn(phen)3]I8: complementary orthogonality and complementary helicity
Contrasting crystal supramolecularity for [Fe(phen)3]I8 and [Mn(phen)3]I8: complementary orthogonality and complementary helicity
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DOI：
10.1039/b008381j
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发表时间：
2001
期刊：
影响因子：
3.1
通讯作者：
C. Horn;M. Scudder;I. Dance
中科院分区：
文献类型：
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作者：
C. Horn;M. Scudder;I. Dance
报道了 [Fe(phen)3]I8 和 [Mn(phen)3]I8 的结晶、晶体结构和晶体超分子性分析。结晶[Fe(phen)3]I8 包含[M(phen)3]2+ 配合物之间的一维延伸六重芳基环(6AE) 的第一个例子。链间域包含扭曲的 I82- 离子，这些离子沿着域的轴平移形成聚碘螺旋。多碘化物螺旋的部分插入每个[Fe(phen)3]2+复合物中phen配体之间的凹槽中：即使延伸的6AE链不是螺旋状，这些凹槽在每个复合物中以螺旋方式倾斜，并且多碘化物螺旋和阳离子链之间存在良好的局部配准和几何互补性。多碘化物螺旋通过协调的 C-H⋯I 相互作用得到进一步支撑。该晶体接近三角对称。相比之下，结晶[Mn(phen)3](I3)(I5)既不包含6AE，也不包含[M(phen)3]z配合物特征的平行四重芳基环抱(P4AE)，但确实显示出相对罕见的同手性P4AE实例。 [Mn(phen)3]2+配合物与I3-和I5-离子的缔合有效且紧密，很好地体现了[M(phen)3]z配合物与多碘化物的互补正交性。 [Mn(phen)3](I3)(I5)的不对称单元中有两个分子式单元，高自旋[Mn(phen)3]2+阳离子从低自旋[Fe(phen)3]2+的八面体立体化学中扭曲而来。讨论了这两种结构是否可以视为取代多晶型物、哪种结构更稳定以及是否可以与另一种结构一起结晶的问题。
The crystallisation, crystal structures, and analyses of crystal supramolecularity for [Fe(phen)3]I8 and [Mn(phen)3]I8 are reported. Crystalline [Fe(phen)3]I8 contains the first example of one-dimensionally extended sixfold aryl embraces (6AE) between [M(phen)3]2+ complexes. The interchain domains contain twisted I82– ions, which are translated along the axis of the domain to form polyiodide helices. Sections of the polyiodide helix slot into the grooves between the phen ligands in each [Fe(phen)3]2+ complex: these grooves are canted in helical fashion in each complex, even though the extended 6AE chain is not helical, and there is good local registry and geometrical complementarity between the polyiodide helices and the cation chains. The polyiodide helices are buttressed further by concerted C–H⋯I interactions. The crystal approaches trigonal symmetry. In contrast, crystalline [Mn(phen)3] (I3)(I5) contains neither 6AE nor the parallel fourfold aryl embraces (P4AE) characteristic of [M(phen)3]z complexes, but does display a relatively rare instance of a homo-chiral P4AE. The association of [Mn(phen)3]2+ complexes and the I3– and I5– ions is effective and close, and manifests well the complementary orthogonality of [M(phen)3]z complexes and polyiodides. There are two formula units in the asymmetric unit of [Mn(phen)3](I3)(I5), and the high-spin [Mn(phen)3]2+ cations are distorted from the octahedral stereochemistry of low-spin [Fe(phen)3]2+. The issues of whether these two structures could be regarded as substitutional polymorphs, and which is the more stable, and whether each could crystallise with the structure of the other, are discussed.