gem-dimethyl substitution at the four benzylic carbons of the ring on the internal dynamics of two-station [2]rotaxanes. Such structural modification of the polyamide macrocycles promotes a drastic change of the internal dynamics as shown by variable-temperature (VT) 1H NMR experiments. We determined that the shuttling rates of the octamethylated macrocycle along a series of symmetrical threads were significantly
在这项研究中,我们展示了环的四个苄基碳上的偕二甲基取代对双站[2]轮烷内部动力学的影响。变温 (VT) 1 H NMR 实验表明,聚酰胺大环的这种结构修饰促进了内部动力学的巨大变化。我们确定,与未取代的环相比,八甲基化大环沿着一系列对称线的穿梭速率明显更快。这种效果在基于富马酰胺的系统中尤其明显,其速率比模型系统快 27 倍。