Macrocyclic polylactams

A new macrocyclic polylactam-type neutral receptor for anions - structural aspects of anion recognition, A. Szumna and J. Jurczak, Eur. J. Org. Chem., 2001, 4031. 

Organosilicon derivatives can be used for the covalent-template synthesis of macrocyclic polylactams [28, 29]. The method includes conversion of acyclic dia-... 

Macrocyclic polycarbonyls are cyclic ligands containing carbonyl functionalities. Several categories come under this heading the macrocyclic oligoketones (7), the polylactones (8) and the polylactams (9). 

Polyoxa macrocycles, known more commonly as the crown ethers, comprise an extensive area of research, with a repertoire of types and variations. Some of these macrocycles have been utilized predominantly for purposes other than metal ion complexation, and these will not be discussed in depth in this review. Included in this latter category are the polycarbonyls, polylactones,polylactams and carcerands. " ... 

The ions of cobalt(III), rhoditun(III) and iridium(III) are the best templates for assembling octahedral complexes with ligands of the sepulchrate type. To obtain macrocyclic polylactones and polylactams, templates with covalent character bonds, such as Sn, Si, Sb, or B, are used. Copper(I) is the most convenient centre for the synthesis of catenanes. 

A unique approach to the controlled design of such systems as macrocyclic polylactones, polylactams and related compounds has been developed [1]. The synthesis of these substances, called biomimetic macrocyclic molecules by reason of their resemblance to naturally occuring ionophores (such as valinomycin, nonacdn, enniatin and enterobactin [2-5]), is carried out by a covalent-template method. This description arises from the use of elements forming covalent bonds (tin, silicon, antimony, boron) as matrices. 

Macrocyclic poly lactones, polylactams and related compounds 459... 

The production of new macrocyclic systems has become possible due mainly to the development of new template centres for specific ligand products, such as the covalent-template approach to the synthesis of macrocyclic polylactones, polylactams and related compounds. Also of note is the the assembly of the cat-echoylamide systems H6L1019 and H6L1022 on an iron(III). In these situations the specific arrangement of functional groups required for macrocyclisation is a result of complex formation. 

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