Threading of di-, tri-, and tetra(ethylene glycol) through the macrocycle BPX26C6 in the presence of templating Na+ ions was proven by the synthesis of the corresponding [2]rotaxanes under solvent-free conditions. Among them, a [2]rotaxane featuring both tetra(ethylene glycol) and carbamate stations behaves as a molecular switch that can be controlled reversibly through the application of the KTFPB/[2
host molecule in which one diethyleneglycolchain (i.e., a loop possessing only three oxygen atoms) incorporated along with two phenolic aromatic rings is linked by a xylene spacer into a macroring. The design of the molecular structure of this macrocycle “amplifies” any potential [cation···π], [N+−H···π], and [N+C−H···π] interactions between the dibenzylammonium (DBA+) ion and the phenolic rings of
我们报告了一个新的宿主分子,其中一个二甘醇链(即,仅具有三个氧原子的环)与两个酚醛芳香环结合在一起,并通过二甲苯间隔基连接到一个大环上。该大环分子结构的设计“放大”了二苄基铵之间的任何可能的[阳离子···π],[N + -H···π]和[N + CHH···π]相互作用( DBA +)离子和大环的酚环;因此,这些物质在CD 3 NO 2中显示出非常强的结合亲和力(K a = 15000 M - 1)。该大环还以[2]假轮烷形式与双吡啶鎓离子配位,这使其成为已知的在溶液中络合DBA +和双吡啶鎓离子的最小的大环(即25元环)。为了明确确认溶液中存在这些假轮烷,我们合成了它们相应的互锁分子,即轮烷和链烷。
PSEUDOROTAXANES, ROTAXANES AND CATENANES FORMED BY METAL IONS TEMPLATING
申请人:NATIONAL TAIWAN UNIVERSITY
公开号:US20140350242A1
公开(公告)日:2014-11-27
A pseudorotaxane, a rotaxane and a catenane are provided. The pseudorotaxane includes at least a macrocyclic host molecule, a guest molecule, and a metal ion. The host molecule contains at least a binding unit and an aromatic linking spacer. The guest molecule has at least a recognition unit. The metal ion is used to template the threading of the guest molecule through the macrocycle host molecule by coordinating to a binding pocket formed from the binding unit of the macrocycle and the recognition moiety of the guest molecule. Rotaxanes or catenanes can be synthesized from the pseudorotaxane complexes, with or without the metal template ion in their molecular structures.
A [2]rotaxane has been constructed through metal ion-templated pseudorotaxane formation from a weakly interacting host (bis-p-xylyl[26]crown-6)/guest (diphenylurea derivative) complex and post-assembly modification to form another weakly interacting tertiary ammonium ion recognition site for the host. The combination of this pair of weakly interacting components allowed bifunctional (pH, Na+ ions)
describe a [2]rotaxane molecule that exhibits distinct signals in its (1)H NMR spectra upon the complexation of physiologically important Li(+), Na(+), Mg(2+) and Ca(2+) ions; thus, the identification of these metal ions in solution is possible from the analysis of a single (1)H NMR spectrum of a single molecular sensor.