Macropolycyclic ligands metal complexes

Macropolycyclic ligands, 2,942 classification, 2,917 metal complexes binding sites, 2, 922 cavity size, 2,924 chirality, 2, 924 conformation, 2,923 dimensionality, 2, 924 electronic effects, 2, 922 shaping groups, 2,923 structural effects, 2,922 molecular cation complexes, 2,947 molecular neutral complexes, 2,952 multidentate, 2,915-953 nomenclature, 2,920 Macro tetrolide actins metal complexes, 2,973 Macrotricycles anionic complexes, 2,951 cylindrical... 

Macrocycle obtained by the condensation of phenol rings with formaldehyde and amenable to substitution both on the phenolic functions and on the para positions of the phenol rings Macropolycyclic ligand forming a cage Metal ion complex with a cryptand... 

Because the definition of metal ion encapsulation or its absence is, to a certain extent, ambiguous, we first describe the conventional criteria that we use to restrict the scope of the compounds to be considered. The major signs of complexation (formation of a complex) with an encapsulated metal ion are (a) a three-dimensional cavity (capsule, cage) produced by a macropolycyclic ligand and (b) metal ion coordinating heteroatoms in this cavity that isolate this metal ion from the environment. 

Our present aim is to summarize the results obtained in the design of coreceptors capable of performing molecular recognition. Complexation of two or more metal ions by various macropolycyclic ligands to form di- or polynuclear cryptates will not be considered here (see ref. [15]). The discussion will be limited to substrate recognition by ditopic coreceptors for polyatomic molecular cations and anions and to developments towards poly topic coreceptors. 

Macropolycyclic polyamine ligand (a form of cryptand leading to extremely inert metal ion complexes)... 

Compounds 1 and 2, represented in Scheme 149, contain a second shell that completely excludes the extrusion of the metal ion without rupture of the clathrochelate framework and enforces a cage by additional covalent bonds. The first ligand of this type with a partially formed secondary structure was synthesized (see Chapter 2, Scheme 73). In this case, the encapsulated metal ion, exerting no influence on the number of physical characteristics of the complex such as solubility, volatility, and others, can be regarded only as the matrix that forms the macropolycyclic system [433]. 

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