Cyclophanes definition

Carcerands and Hemicarcerands, p. 189 Concave Reagents, p. i /1 Crown Ethers, p. 326 Cryptophanes, p. 340 Cyclodextrins, p. 398 Cyclodextrins, Applications, p. 405 Cyclophanes Definition and Scope, p. 414 Enzyme Mimics, p. 546 Macrocycle Synthesis, p. 830 Organometallic Anion Receptors, p. 1006 Soft and Smart Materials, p. 1302 X-Ray Crystallography, p. 1586... 

Cyclophanes Definition and Scope, p. 414 Cyclophanes Endoacidic, Endohasic, and Endolipophilic Cavities, p. 424... 

Biological Ligands, p. 88 Chiral Guest Recognition, p. 236 Complexation of Fullerenes, p. 302 Concave Reagents, p. 5 i 1 Cyclophanes Definition aiTd Scope, p. 414 Drug Delivery, p. 484 Glycoluril-Based Hosts, p. 597 Podands, p. 1106... 

On the basis of this definition (Fig. 1) the following classes of chiral compounds will be treated in this article cyclophanes, bridged anulenes and [8]anulenes, and ( )-cyclooctene and related structures. As mentioned above, metallocenes will be excluded. 

There is no uniformly accepted definition of cyclophanes. Usually one understands under this name a macrocyclic or macrobicyclic compound having built-in aromatic rings. However, IUPAC rules define (cyclo)phanes much more broadly they include linear molecules containing rings that are not necessarily... 

The International Union of Pure and Applied Chemistry (IUPAC) produced a set of rules for the definition of highly complex ring systems. Under these guidelines a cyclophane (i) has a mancude ... 

Stereoselectivity. See Asymmetric induction Axial/equatorial-, Cis/trans-, Enantio-, Endo/exo- or Erythro/threo-Selectivity Inversion Retention definition (e.e.), 107 footnote Steric hindrance, overcoming of in acylations, 145 in aldol type reactions, 55-56 in corrin synthesis, 261-262 in Diels-Alder cyclizations, 86 in Michael type additions, 90 in oiefinations Barton olefination, 34-35 McMurry olefination, 41 Peterson olefination, 33 in syntheses of ce-hydrdoxy ketones, 52 Steric strain, due to bridges (Bredt s rule) effect on enolization, 276, 277, 296, 299 effect on f3-lactam stability, 311-315 —, due to crowding, release of in chlorophyll synthesis, 258-259 in metc-cyclophane rearrangement, 38, 338 in dodecahedrane synthesis, 336-337 in prismane synthesis, 330 in tetrahedrane synthesis, 330 —, due to small angles, release of, 79-80, 330-333, 337... 

Among the first to exploit totally synthetic water soluble host compounds to catalyze chemical reactions were Tabushi et. al. who found an accelerating influence of their newly developed polyammonium cyclophane 1 on the hydrolysis of aromatic chloroacetates These authors showed conclusively that a rapid association of substrate and 1 proceeds the rate limiting attack of solvent on the ester group. This step is amenable to buffer catalysis, too. Some relevant rate data are given in Table 1. The evaluation of these data now depends largely on definitions. Tabushi et al. chose to view their results in terms of a kinetic sul trate specificity manifested in ratios. As a corollary they state a marked specificity in the conversion of substrates 2-4. This is formally corr t but it bears the danger of misinterpretation and is certainly seductive to draw faulty conclusions. 

Calixarenes developed by Gutsche belong to a family of cyclophanes by definition, and much attention has focused on their catalytic functions as artificial enzymes based on their versatile molecular recognition... 

Abstract. A series of water-soluble cyclophanes, made by connecting two diarylmethane units and two bridging chains via four nitrogens, were found to provide hydrophobic cavities of definite shape and size for forming inclusion complexes with various organic compounds in aqueous solution. Some chemical modifications of these cyclophanes are described. 

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