Remote Impacts of Methyl Substituents on the Guest-Binding Ability of Self-Assembled Cages
Remote Impacts of Methyl Substituents on the Guest-Binding Ability of Self-Assembled Cages
复制标题
甲基取代基对自组装笼客体结合能力的远程影响
DOI：
10.1002/asia.201301642
复制
发表时间：
2014
期刊：
影响因子：
--
通讯作者：
M. Fujita
中科院分区：
文献类型：
--
作者：
Y. Fang;T. Murase;M. Fujita
我们合成了自组装配位笼，其中 1,10-菲咯啉衍生物作为封端配体。菲咯啉配体 2,9 位的取代基覆盖笼的外部，但对笼内的客体结合有影响。在 2,9 位引入甲基使笼能够容纳四苯基硅烷。悬在笼框架上的庞大异丙叉基团通过与笼的芳香面板的π-π相互作用显着缩小了笼腔。异亚丙基取代基的对甲基是高温下4,4'-二甲氧基苯偶酰在笼内受限运动的决定因素。因此，远离客体结合位点的一个甲基的存在或不存在，会对客体物种和笼内的运动产生显着差异。
We synthesized self‐assembled coordination cages in which 1,10‐phenanthroline derivatives serve as capping ligands. Substituents at the 2,9‐positions of the phenanthroline ligand covered the outside of the cage but had an impact on the guest binding inside the cage. Introduction of methyl groups at the 2,9‐positions allowed the cage to accommodate tetraphenylsilane. Bulky mesityl groups overhanging the cage framework significantly shrunk the cage cavity through π–π interactions with the aromatic panels of the cage. Thep‐methyl group of the mesityl substituent was a determinant of the restricted motion of 4,4′‐dimethoxybenzil inside the cage at high temperature. Thus, the presence or absence of one methyl group, which is far from the guest‐binding site, makes a significant difference in the guest species and motions inside the cage.