作者:Antje Vetter、Werner Abraham
DOI:10.1039/c0ob00270d
日期:——
Novel rotaxanes containing two 9-aryl-9-methoxy-10-methyl-9,10-dihydroacridine moieties (acridanes) at both ends of the molecular axle as recognition stations for the tetracationic ring CBQT4+ were synthesized together with their acridinium counterparts. A new concept of controlling the ring movement within rotaxanes has been realized with these rotaxanes. Owing to Brownian molecular movement, the ring shuttles from one end of the axle to the other one in acridane rotaxanes. The shuttle process is stopped by converting two or one of the acridane stations into the corresponding acridinium unit. If both acridanes are transformed by addition of an acid, the ring resides on evasive stations present in the center of the axle. Photons convert only the unoccupied acridane station, thus the ring remains on the unchanged acridane station. The shuttle process can be switched on by addition of a base and by the thermal reaction of the methoxide with the formed acridinium ion, respectively.
我们合成了分子轴两端含有两个 9-芳基-9-甲氧基-10-甲基-9,10-二氢吖啶分子(吖啶)作为四阳离子环 CBQT4+ 识别位点的新型轮烷及其吖啶对应物。这些轮烷实现了控制轮烷内环运动的新概念。由于布朗分子运动,吖啶轮烷中的环会从轴的一端穿梭到另一端。通过将两个或一个吖丙烷位点转化为相应的吖啶鎓单元,可停止穿梭过程。如果两个吖啶烷都通过添加酸进行转化,那么环就会停留在轴中心的闪避台上。光子只转换未被占用的吖丙烷位点,因此环停留在未发生变化的吖丙烷位点上。加入碱和甲氧基与形成的吖啶鎓离子发生热反应可分别开启穿梭过程。