School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China.
Guangxi Institute of Chinese Traditional Medical & Pharmaceutical Science and Guangxi Key Laboratory of Tradtitional Chinese Medicine Quality Standards, Nanning 530022, China.
Molecules. 2019 Jul 24;24(15):2693. doi: 10.3390/molecules24152693.
Two types of mono-ester-functionalized pillar[5]arenes, P1 and P2, bearing different side-chain groups, were synthesized. Their host-guest complexation and self-inclusion properties were studied by H NMR and 2D nuclear overhauser effect spectroscopy (NOESY) NMR measurements. The results showed that the substituents on their phenolic units have a great influence on the self-assembly of both pillar[5]arenes, although they both could form stable pseudo[1]rotaxanes at room temperature. When eight bulky 4-brombutyloxy groups were capped on the cavity, instead of methoxy groups, pseudo[1]rotaxane P1 became less stable and its locked ester group in the inner space of cavity was not as deep as P2, leading to distinctly different host-guest properties between P1 and P2 with 1,6-dibromohexane. Moreover, pillar[5]arene P1 displayed effective molecular recognition toward 1,6-dichlorohexane and 1,2-bromoethane among the guest dihalides. In addition, the self-complex models and stabilities between P1 and P2 were also studied by computational modeling and experimental calculations.
两种单酯官能化的[5]柱芳烃 P1 和 P2 被合成，它们带有不同的侧链基团。通过 1H NMR 和二维核 Overhauser 效应谱（NOESY）NMR 测量研究了它们的主客体络合和自包含性质。结果表明，酚单元上的取代基对两种[5]柱芳烃的自组装有很大影响，尽管它们都可以在室温下形成稳定的假[1]轮烷。当空腔上被八个大的 4-溴丁氧基取代，而不是甲氧基时，假[1]轮烷 P1 变得不太稳定，其腔内锁定的酯基没有 P2 深，导致 P1 和 P2 与 1,6-二溴己烷之间具有明显不同的主客体性质。此外，[5]柱芳烃 P1 对客体二卤代烷中的 1,6-二氯己烷和 1,2-溴乙烷表现出有效的分子识别。此外，还通过计算建模和实验计算研究了 P1 和 P2 之间的自复合物模型和稳定性。
