Host-guest chemistry overview

A discussion of the state of the art of ISEs for every target ion for which such sensors have been developed would have been well beyond the scope of this chapter. However, we hope that this chapter gives the interested reader an overview of state-of-the-art ionophore-based potentiometry that goes beyond a superficial treatment and illustrates what developers of ISEs need to consider when they want to take advantage of host-guest chemistry to fabricate highly selective sensors. As some of the examples show, analytical chemists have developed a variety of techniques for the optimization of ionophore-doped membranes. This has led to sensors with remarkably high selectivities and extraordinarily low detection limits. 

This chapter presents a selective glimpse of this dynamic family of spherical macromolecnles for newcomers to the topic in order to help them better appreciate the field that has been extensively reviewed elsewhere. This chapter is divided into several parts to emphasize the structmal diversity and their potential applications. First, a study of the internal structure of the dendritic architecture, emphasizing the different types, followed by a study of their interactions with other molecules or atoms, such as in the case of host-guest chemistry, molecular recognition, or encapsulation inside the dendrimer. Finally, there is a small section that will address the intermolecular interactions of dendrimers and dendrons to either themselves or other nano-objects. In this past quarter century, tens of thousands of papers have been published producing a wide variety of different dendritic architectures with varied structural components capable of novel supramolecular interactions. Therefore, only an overview describing their structure with representative examples and practical purposes will be discussed, when appropriate. 

These characteristic features allow the exploitation of luminescent MOFs as chemical sensors. The rational design of MOFs for specific sensing applications and the investigation of their luminescent response is an emerging research field. The purpose of this chapter is to present an overview of the recent development on host-guest chemistry for the preparation of luminescent MOFs (Fig. 1). 

The present book provides a state-of-the-art view on some of these topics including topological, conformational and host-guest problems written by five recognized experts. Because of this, the book lays no claim to being a quantitative overview of cyclophane chemistry. However, in this latter respect, the reader is referred to the excellent monographs produced by F. Diederich [(1991)... 

The field of supramolecular chemistry is concerned with a large number of systems ranging from simple host-guest complexes to more complicated solution assemblies, as well as two-dimensional (organized monolayers) and three-dimensional assemblies (crystalline solids). Nonco-valent interactions play an important role in the kinetic assembly and thermodynamic stabilization of all these systems and constitute their most distinctive feature. Electron-transfer reactions can obviously be affected by supramolecular structures, but the reverse is also true. It is possible to alter the structure and the thermodynamic stability of supramolecular assemblies using electrochemical (redox) conversions. In other words, electron-transfer reactions can be utilized to exert some degree of control on supramolecular aggregates. Provided in this article is an overview of the interplay between supramolecular structure and electron-transfer reactions. 

Weber, E., Vogte, F. (1981) Crown-type compounds - An introductory overview. In Host-Guest Complex Chemistry I. Topics in Current Chemistry 98, 1-41 (Vogte, F., editor). Berlin Springer-Verlag... 

Weber, E., and Vogtle, E, Crown-type compounds—an introductory overview, in Host-Guest Complex Chemistry, Vogtle, E, Ed., Springer Verlag, Berlin, 1981, 11. Hemery, E, Warzelhan, V, and Boileau, S., Kinetics of ring opening of propylene sulfide. 1. Alkali metal and cryptated metal carbonyl. Polymer, 21, 77, 1980. 

The brief overview of intercalation chemistry presented above shows that the subject encompasses a fascinating variety of solid state reactions between two- or three-dimensional host materials and guest atoms and molecules. Not all host material that... 

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