Macrocycle cage system

On the other hand, host-guest systems being composed of preorganized macrocyclic, cage-type or rigid acyclic host molecules... 

The combination of metal ions and appropriate ligands to form macrocyclic, cage-like, and extended network structures has become a powerful tool for the construction of systems having cavities, pores, or channels, and is currently one of the most important topics in chemical and material sciences. Applications are visualized for a wide range of fields, such as ion and molecular recognition, sorption, filtration,... 

Abstract This review presents an overview of the area of anion-templated synthesis of molecules and supramolecular assemblies. The review is divided into two main sections the first part deals with anion-templated systems where the final products are linked by bonds that are not reversible under the conditions of the experiment Several recent examples of macrocycles, cages and interlocked species are presented in this section. The second part of the chapter, presents a discussion of anion-templation in systems containing reversible bonds that give rise to dynamic combinatorial libraries (either by formation of coordination metal-ligand bonds or by reversible covalent bonds). 

Holbrey et al. have developed a molecular mechanics model for l,2-C2BioHi2 and derivative cages distances are constrained in the model. The study has been extended to include macrocyclic thioether systems in which the C-substituents in l,2-C2R2BioHio are linked into a (typically thio) macrocycle (see also section 14). 

Metalated container molecules can be viewed as a class of compounds that have one or more active metal coordination sites anchored within or next to a molecular cavity (Fig. 2). A range of host systems is capable of forming such structures. The majority of these compounds represent macrocyclic molecules and steri-cally demanding tripod ligands, as for instance calixarenes (42), cyclodextrins (43,44), and trispyrazolylborates (45-48), respectively. In the following, selected types of metalated container molecules and their properties are briefly discussed and where appropriate the foundation papers from relevant earlier work are included. Porphyrin-based hosts and coordination cages with encapsulated metal complexes have been reviewed previously (49-53) and, therefore, only the most recent examples will be described. Thereafter, our work in this field is reported. 

An overview of the synthesis, structure, photophysical properties, and applications of squaraine rotaxanes as fluorescent imaging probes and chemosensors is provided in a recent review [67]. Although a variety of squaraine dyes form rotaxanes with the molecular cage 25 or with a tetralactam macrocyclic system introduced by Leigh and co-workers [16, 17], there is no evidence in the literature that conventional cyanine dyes can be embedded in these macrocycles. 

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