Macrobicyclic application

Somewhat unanticipated applications can arise. For example, a process for the production of ultrapure hydrogen peroxide for the electronics industry has been patented recently,1425 which uses the macrobicyclic hexamine complex (29) supported on an inert material for dioxygen... 

Cryptands, 42 122-124, 46 175 nomenclature, 27 2-3 topological requirements, 27 3-4 Cryptate, see also Macrobicyclic cryptate 12.2.2], 27 7-10 applications of, 27 19-22 cylindrical dinuclear, 27 18-19 kinetics of formation in water, 27 14, 15 nomenclature, 27 2-3 spherical, 27 18 stability constants, 27 16, 17 Crystal faces, effect, ionic crystals, in water, 39 416... 

The reaction is generally applicable to further extension for making macrobicyclic diamines4 with bridgehead nitrogen atoms by using monocyclic diimines and an appropriate acid chloride. The main... 

Relatively simple syntheses for the majority of macrobicyclic complexes, compared with conventional techniques for the preparation of macrocyclic compounds, have made such complexes attractive not only for research, but also for practical application as electron carriers, catalysts for electro- and photochemical processes, and some other purposes (e.g., protein redox titrants, biological electrochemical mediators, and ionophore and electrode modifiers). 

Cryptate complexes with macrobicyclic ligands containing three bipy units, in which the Ln + ion is contained within a ligand cavity, have been synthesized. Such ligands will complex Ln + ions, such as Eu + and Sm +, under conditions where Ln + ions are not. An application has been using lanthanide cryptates of the early lanthanides (La, Ce, Eu) as catalysts in the hydrolysis of phosphate monoesters, diesters, and triesters. Schiff base complexes can be synthesized by the reaction of a lanthanide salt with a diamine and a suitable carbonyl derivative such as 2,6-diacetylpyridine. 

An established area of application of macrocyclic polyethers is the stereoselective complexation of chiral guest primary alkylammonium salts by optically active host macrocycles. Full details of the resolution, optical stability, and inclusion into chiral hosts of the binaphthol (84), and also of the chiral recognition properties of crowns [e.g. (85)] based on simple carbohydrate precursors, have been reported this year. An extension of the latter work" utilizes derivatives of the more complex carbohydrates D-glucose and D-galactose. The macrobicyclic polyethers (86) derived from D-glycerol or pentaerythritol have been suggested as potential chiral (at the bridgeheads) cryptands. 

The introduction of dipolar aprotic solvents " and the discovery of macrocyclic (crown ethers and macrobicyclic polyethers (cryptands represent some of the more significant steps. Dating from the late sixties, a new general technique was developed phase-transfer catalysis (PTC). PTC has the advantages of being extremely simple and economical and so met with immediate success in industrial applications. 

The practical and effective synthesis of photoactive lanthanide cryptates (1), capable of effective light conversion, has found application in the design of novel fluorescent immunoassay systems. The macrobicyclic bipyridyl cryptands prevent the normal solvation quenching of these cations. Remarkably effective DNA cleavage was accomplished using intercalators (2) based on 2,7-diazapyrenium cations. 

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