Wydział Chemii, Uniwersytet Wrocławski , ul. F. Joliot-Curie 14, 50-383 Wrocław, Poland.
J Am Chem Soc. 2015 Feb 4;137(4):1643-9. doi: 10.1021/ja511951x. Epub 2015 Jan 9.
Nonclassical nanotube end-caps have been constructed from strain-free heterocyclic precursors using a one-step synthetic procedure, involving multiple nickel-mediated Ullmann couplings. These systems consist of tubular macrocyclic sections that are tightly capped on one side with a bridging benzene ring, forming deep, chemically accessible cavities. The end-caps are characterized by exceptionally high internal strain energies reaching 144 kcal/mol. The optical absorption and emission properties of these molecules show a marked dependence on conjugation length and geometrical factors. The mechanism of end-cap formation, investigated using DFT calculations, relies on precise timing of transmetalation and reductive elimination events.
非经典纳米管端帽已由无应变杂环前体通过一步合成方法构建，该方法涉及多个镍介导的乌尔曼偶联。这些系统由管状大环段组成，一侧用桥连苯环紧密封端，形成深的、化学可及的空腔。端帽的特征在于具有高达 144 kcal/mol 的异常高的内部应变能。这些分子的光吸收和发射性质明显依赖于共轭长度和几何因素。使用 DFT 计算研究了端帽形成的机制，该机制依赖于转金属化和还原消除事件的精确定时。
