Institut für Anorganische Chemie der Universität Regensburg, 93040 Regensburg, Germany.
Chemistry. 2012 Jan 16;18(3):829-35. doi: 10.1002/chem.201103141. Epub 2011 Dec 13.
Treatment of the pentaphosphaferrocene [CpFe(η(5)-P(5))] with Cu(I) halides in the presence of different templates leads to novel fullerene-like spherical molecules that serve as hosts for the templates. If ferrocene is used as the template the 80-vertex ball [Cp(2)Fe]@[{CpFe(η(5)-P(5))}(12){CuCl}(20)] (4), with an overall icosahedral C(80) topological symmetry, is obtained. This result shows the ability of ferrocene to compete successfully with the internal template of the reaction system [CpFe(η(5)-P(5))], although the 90-vertex ball [{CpFe(η(5):η(1):η(1):η(1):η(1):η(1)-P(5))}(12)(CuCl)(10)(Cu(2)Cl(3))(5){Cu(CH(3)CN)(2)}(5)] (2 a) containing pentaphosphaferrocene as a guest is also formed as a byproduct. With use of the triple-decker sandwich complex [(CpCr)(2)(μ,η(5)-As(5))] as a template the reaction between [CpFe(η(5)-P(5))] and CuBr leads to the 90-vertex ball [(CpCr)(2)(μ,η(5)-As(5))]@[{CpFe(η(5)-P(5))}(12){CuBr}(10){Cu(2)Br(3)}(5){Cu(CH(3) CN)(2)}(5)] (6), in which the complete molecule acts as a template. However, if the corresponding reaction is instead carried out with CuCl, cleavage of the triple-decker complex is found and the 80-vertex ball [CpCr(η(5)-As(5))]@[{Cp*Fe(η(5)-P(5))}(12){CuCl}(20)] (5) is obtained. This accommodates as its guest [CpCr(η(5)-As(5))], which has only 16 valence electrons in a triplet ground state and is not known as a free molecule. The triple-decker sandwich complex [(CpCr)(2)(μ,η(5)-As(5))] requires 53.1 kcal mol(-1) to undergo cleavage (as calculated by DFT methods) and therefore this reaction is clearly endothermic. All new products have been characterized by single-crystal X-ray crystallography. A favoured orientation of the guest molecules inside the host cages has been identified, which shows π⋅⋅⋅π stacking of the five-membered rings (Cp and cyclo-As(5)) of the guests and the cyclo-P(5) rings of the nanoballs of the hosts.
用 Cu(I)卤化物与五磷杂二茂铁[CpFe(η(5)-P(5))]在不同模板存在下处理，得到了新型富勒烯状球形分子，它们作为模板的主体。如果使用二茂铁作为模板，则得到 80 顶点球[Cp(2)Fe]@[{CpFe(η(5)-P(5))}(12){CuCl}(20)]（4），具有整体的二十面体 C(80)拓扑对称性。这一结果表明二茂铁具有成功竞争反应体系内部模板[CpFe(η(5)-P(5))]的能力，尽管也形成了作为副产物的包含五磷杂二茂铁作为客体的 90 顶点球[{CpFe(η(5)：η(1)：η(1)：η(1)：η(1)：η(1)-P(5))}(12)(CuCl)(10)(Cu(2)Cl(3))(5){Cu(CH(3)CN)(2)}(5)]（2a）。用三夹层夹心配合物[(CpCr)(2)(μ,η(5)-As(5))]作为模板，[CpFe(η(5)-P(5))]与 CuBr 的反应得到 90 顶点球[(CpCr)(2)(μ,η(5)-As(5))]@[{CpFe(η(5)-P(5))}(12){CuBr}(10){Cu(2)Br(3)}(5){Cu(CH(3)CN)(2)}(5)]（6），其中完整的分子作为模板。然而，如果用 CuCl 进行相应的反应，则发现三夹层夹心配合物发生断裂，得到 80 顶点球[CpCr(η(5)-As(5))]@[{Cp*Fe(η(5)-P(5))}(12){CuCl}(20)]（5）。它容纳了其客体[CpCr(η(5)-As(5))]，其在三重基态下只有 16 个价电子，并且不作为游离分子存在。三夹层夹心配合物[(CpCr)(2)(μ,η(5)-As(5))]需要 53.1 kcal mol(-1)才能发生断裂（通过 DFT 方法计算），因此该反应显然是吸热的。所有新产品均通过单晶 X 射线晶体学进行了表征。已经确定了客体分子在主体笼内的优选取向，这表明了客体的五元环（Cp 和环-As(5))与主体纳米球的环-P(5)之间的π⋅⋅⋅π堆积。
