Fang Yu, Murase Takashi, Fujita Makoto
Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan), Fax: (+81) 3-5841-7257.
Chem Asian J. 2014 May;9(5):1321-8. doi: 10.1002/asia.201301642. Epub 2014 Feb 23.
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. The p-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.
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位的取代基覆盖在笼的外部，但对笼内客体的结合有影响。在2,9位引入甲基使笼子能够容纳四苯基硅烷。伸出笼框架的庞大均三甲苯基基团通过与笼的芳环板的π-π相互作用显著缩小了笼腔。均三甲苯基取代基的对甲基是高温下笼内4,4'-二甲氧基二苯甲酮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与否，对笼内客体种类和运动有显著影响。
