刚性六元苯乙炔大环能够在分子间侧链多重氢键和π-π堆积作用驱动下自组装形成纳米管，这种纳米管不但具有独特的物质传输特性，在分子识别、药物递送、反应催化及分子器件等方面也具有潜在应用价值。但是依靠非共价键构筑起来的纳米管稳定性差且长度不可控，限制了其具体应用，构建长度可控的稳定纳米管是超分子化学领域的一项重要挑战。本博士学位论文在文献调研的基础上，设计合成了水溶性的六元苯乙炔大环和带有疏水骨架的线性客体分子，研究了大环化合物的自组装性质和主客体化学，取得如下的研究成果：

论文第一部分，通过多步有机反应设计合成了一系列寡聚乙二醇修饰的六元苯乙炔大环分子，并采用核磁共振氢谱、碳谱和质谱进行了表征和结构确证。

论文第二部分采用核磁共振氢谱、紫外光谱、荧光光谱和圆二色谱研究了水溶性六元苯乙炔（m-PE）大环在有机溶剂和水中的自组装行为，探究了不同溶剂中驱动大环组装的多种非共价相互作用。证明了在非极性的CCl₄和弱极性的CHCl₃中，组装的驱动力主要是π-π堆积和侧链N-H···O=C类型氢键的双重诱导作用；在极性溶剂如MeOH和H₂O中，组装的驱动力主要是较强的疏溶剂作用和疏水作用。

论文第三部分设计合成了一系列带有寡聚对亚苯基乙炔基（p-PE）疏水骨架和寡聚乙二醇亲水侧链的线性客体分子，分别采用荧光光谱、圆二色谱、一维核磁共振、二维核磁共振、质谱、等温量热实验和理论计算等方法研究了大环与客体分子在水溶液中的主客体相互作用。在疏水作用驱动下，客体分子与大环形成动力学稳定的准轮烷结构，每个准轮烷结构包含了被大环的管状堆积包裹的两个相同的客体分子，客体分子的长度决定了构成主体的大环分子的数量，从而遏制了大环的“无限”堆叠，可通过调整客体p-PE片段的长度来控制形成管状大环堆叠体的聚集度。

综上所述，在多重非共价相互作用下，大环可组装形成无限长度的纳米管，通过与线性客体分子之间主客体相互作用可形成紧密有序、长度可控的管状自组装结构，这一研究在水溶液中是前所未有的，为将来设计合成长度可控的稳定纳米管提供了理论和实验支持。

Shape-persistent hexakis(m-phenyleneethynylene) (m-PE) macrocycles self-assemble into long nanotubes driven by multiple hydrogen bonding and aromatic π-π stacking interactions. The self-assembling nanotubes show unusual mass-transport properties and are expected to find a variety of applications in molecular recognition, drug delivery, catalysis and molecular devices. However, the self-assembling nanotubes based on weak noncovalent interactions are unstable and the lengths of such nanotubes are undefined, limiting their application. The construction of nanotubes with definite length is of great importance. In this dissertation, a series of water-soluble m-PE macrocycles and guest molecules with hydrophobic backbones were designed and synthesized. The self-assembling behavior and host-guest interactions of the resultant m-PE macrocycles were investigated. The research results are as follows:

In the first part, a series of water-soluble m-PE macrocycles carrying side chains based on oligo(ethylene glycol) were designed and synthesized by multi-step organic reactions. All synthesized compounds were characterized by ¹H NMR, ¹³C NMR, and MS spectra.

In the second part, the self-assembling behavior of water-soluble m-PE macrocycles in organic and aqueous solutions was investigated with ¹H NMR, UV, FL, and CD spectroscopy, respectively and the driving forces in different solvents were probed. In non-polar CCl₄ and low-polar CHCl₃, the driving force for assembly is the cooperation of π-π stacking and side-chain N-H···O hydrogen bonding interactions. In polar solvents such as MeOH and H₂O, the dominant driving force for self-assembly is solvophobic or hydrophobic effects.

In the third part, a series of guest molecules with rod-like segments based on hydrophobic oligo(p-phenylene ethynylene) (p-PE) having precisely defined lengths and water-soluble oligo(ethylene glycol) side chains were designed. The host-guest interactions between water-soluble m-PE macrocycles and the rod-like guests in water were studied using FL, CD, ¹H NMR, 2D NMR, MS spectra, ITC and theoretical calculations. The macrocyclic hosts and rod-like guests assemble into kinetically stable pseudorotaxanes driven by hydrophobic effects, each pseudorotaxane containing a pair of identical guest molecules encased in a tubular stack. The two guest molecules de?ne the number of macrocyclic molecules that comprise the host, and curb the “in?nite” stack growth, resulting in a tubular stack with a cylindrical pore tailoring the length of the p-PE segment of the bound guests.

Thus, the interplay of multiple non-covalent forces aligns the molecules of macrocycles into tubular stacks with cylindrical inner pores that, upon binding rod-like guests, lead to a new series of tight, discrete, and well-ordered tubular assemblies in water. Results and insights presented in this dissertation provide the theoretical and experimental basis for designing and synthesizing controllable and stable nanotubes in the future.