Pillararene-based self-assembled amphiphiles

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

Recent advancements in pillararene-based self-assembled amphiphiles are highlighted and discussed in this review.

Abstract

Pillararenes are a unique group of supramolecular macrocycles, presenting important features and potential applications on account of their intrinsic structural properties and functionality. Developing pillararene-based self-assembled amphiphiles (PSAs) is an efficient approach to translate pillararenes into functional systems and materials for facilitating their practical applications. In this review article, we highlight recent significant advancements in PSAs. A new standard according to the number, solubility, and amphiphilicity of building blocks is employed for dividing PSAs into different categories. The fabrication of PSAs based on various building blocks and supramolecular interactions, and the formation of amphiphile-based self-assemblies are then discussed based on this standard. Furthermore, interesting stimulus-responsiveness to various factors, such as pH, redox, temperature, light, ionic effect, and host–guest competition, generated by the functional groups on various building blocks is summarized, and the corresponding supramolecular interactions in PSAs and their self-assemblies are elaborated. In addition, some important applications of PSAs and their assemblies are discussed. This review not only provides fundamental findings on the construction of PSAs, but also foresees future research directions in this rapidly developing area.

Related collections

Most cited references 110

Record: found
Abstract: found
Article: not found

Pillararenes, a new class of macrocycles for supramolecular chemistry.

Min Xue, Yong Yang, Xiaodong Chi … (2012)

Because of the importance of novel macrocycles in supramolecular science, interest in the preparation of these substances has grown considerably. However, the discovery of a new class of macrocycles presents challenges because of the need for routes to further functionalization of these molecules and good host-guest complexation. Furthermore, useful macrocylic hosts must be easily synthesized in large quantities. With these issues in mind, the recently discovered pillararenes attracted our attention. These macrocycles contain hydroquinone units linked by methylene bridges at para positions. Although the composition of pillararenes is similar to that of calixarenes, they have different structural characteristics. One conformationally stable member of this family is pillar[5]arene, which consists of five hydroquinone units. The symmetrical pillar architecture and electron-donating cavities of these macrocycles are particularly intriguing and afford them with some special and interesting physical, chemical, and host-guest properties. Due to these features and their easy accessibility, pillararenes, especially pillar[5]arenes, have been actively studied and rapidly developed within the last 4 years. In this Account, we provide a comprehensive overview of pillararene chemistry, summarizing our results along with related studies from other researchers. We describe strategies for the synthesis, isomerization, and functionalization of pillararenes. We also discuss their macrocyclic cavity sizes, their host-guest properties, and their self-assembly into supramolecular polymers. The hydroxyl groups of the pillararenes can be modified at all positions or selectively on one or two positions. Through a variety of functionalizations, researchers have developed many pillararene derivatives that exhibit very interesting host-guest properties both in organic solvents and in aqueous media. Guest molecules include electron acceptors such as viologen derivatives and (bis)imidazolium cations and alkyl chain derivatives such as n-hexane, alkanediamines, n-octyltrimethyl ammonium, and neutral bis(imidazole) derivatives. These host-guest studies have led to the fabrication of (pseudo)rotaxanes or poly(pseudo)rotaxanes, supramolecular dimers or polymers, artificial transmembrane proton channels, fluorescent sensors, and other functional materials.

0 comments Cited 368 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Pillar-Shaped Macrocyclic Hosts Pillar[n]arenes: New Key Players for Supramolecular Chemistry.

Tomoki Ogoshi, Tada-aki Yamagishi, Yoshiaki Nakamoto (2016)

In 2008, we reported a new class of pillar-shaped macrocyclic hosts, known as "pillar[n]arenes". Today, pillar[n]arenes are recognized as key players in supramolecular chemistry because of their facile synthesis, unique pillar shape, versatile functionality, interesting host-guest properties, and original supramolecular assembly characteristics, which have resulted in numerous electrochemical and biomedical material applications. In this Review, we have provided historical background to macrocyclic chemistry, followed by a detailed discussion of the fundamental properties of pillar[n]arenes, including their synthesis, structure, and host-guest properties. Furthermore, we have discussed the applications of pillar[n]arenes to materials science, as well as their applications in supramolecular chemistry, in terms of their fundamental properties. Finally, we have described the future perspectives of pillar[n]arene chemistry. We hope that this Review will provide a useful reference for researchers working in the field and inspire discoveries concerning pillar[n]arene chemistry.