This textbook addresses the chemical and physicochemical principles of supramolecular host-guest chemistry in solution. It covers the thermodynamics and dynamics of inclusion and highlights several types of organic hosts. Various applications of host-guest chemistry in analytical and environmental chemistry as well as pharmaceutical and chemical industry demonstrate the versatile usability of molecular cages.

This textbook addresses the chemical and physicochemical principles of supramolecular host-guest chemistry in solution. It covers the thermodynamics and dynamics of inclusion and highlights several types of organic hosts. Various applications of host-guest chemistry in analytical and environmental chemistry as well as pharmaceutical and chemical industry demonstrate the versatile usability of molecular cages.

The scientific and practical interest in coronands (crown ethers), cryptands, podands as complexing agents for cations as well as for anions and neutral low molecular species is undeniable 1,2). The chemistry of crown compounds is steadily increasing. About 250 original papers dealing with crown chemistry appeared only in 1980. New molecules· with crown ether properties are constantly synthesized and new applications discov,?red. Owing to lack of space, only a small number of the original publications is men tioned here. Thus, in the literature compilation only some, but relevant works are selected for each chapter. Whenever possible, reference is made to reviews or review-like articles alone by means of which origin,al works can be consulted. The reviews given under ref. 1) are considered to be the most relevant. The formulae presented in the figures should be understood as representative structures outlining a specific field. 2 Classification of Oligo-/Multidentate Neutral Ligands and of their Complexes Today, a distinction is made between the classical ring oligoethers (crown ethers) and monocyclic coronands, oligocyclic spherical cryptands and the acyclic podands with respect to topological aspects 3). This classification and the topology are illustrated in Fig. 1, each figure representing the minimum number of donor atoms and chain segments characteristic of each class of compounds. Multidentate mono cyclic ligands with any type of donor atoms are called coronands ("crown compounds"), while the term crown ether should be reserved for cyclic oligoethers exclusively containing oxygen as donor atom.

This monograph describes the behavior of molecules confined to small spaces. The small spaces are created by the self-assembly of modules into hollow capsular structures through hydrogen bonding; capsules assembled by metal/ligand binding or other forces are not included. Topics discussed include how assembly of capsules occurs, how molecules get in and out of the capsules, new spatial arrangements (stereochemistry) created in the capsules, and the altered shapes, interactions and reactivities of molecules held inside the small spaces. The descriptions emphasize molecular recognition phenomena and the perspective is that of physical organic chemistry.The book is the first monograph to treat reversible molecular encapsulation. More than 20 university and institute groups worldwide engage in this research, which represents the leading edge of activity in molecular recognition and the physical organic chemistry of confined molecules.