Functional macrocycles

Cyclization of substituted phenylacetylene sequences afforded functionalized macrocycles that were amenable to subsequent manipulation. For example, transesterification of 42 with octanol in the presence of 18-crown-6 ether and potassium carbonate gave the corresponding ester in 85% yield (Scheme 13). The ester functionalities could be reduced by DIBALH to give the hydroxymethyl-substituted macrocycle (43) in 61 % yield. The low yield of this particular transformation is attributed to mechanical losses during purification, due to the highly polar nature of the product. Macrocycle 43 could then be treated with alkyl bromides to give a group of benzyl ether derivatized PAMs. 

Tri- and tetraaza macrocycles A-functionalized with imidazole and pyrazole groups have been coordinated to zinc. The zinc complexes of functionalized 1,5,9-trizacyclododecane and 1,4,8, 11-tetraazacyclododecane have been synthesized, (76) and (77).680-685 The formation constants with the mono-armed 1,5,9-triazacyclododecane were calculated and found to be higher than for the non-functionalized macrocycle and coordination was demonstrated to be through four nitrogen... 

Typical systems. A considerable number of immobilized polyether systems have been synthesized both for phase transfer catalysis as just discussed and for use in a number of analytical applications. Such immobilized systems are generally synthesized by either copolymerization of suitably functionalized macrocycles in the presence of cross-linking agents or by appending functionalized macrocycles to existing polymeric substrates. Structures (184)-(186) give examples of different... 

Dozol, J. F. Scwing-Weill, M. J. Arnaud-Neu, F. Bohmer, V. Ungaro, R. van Veggel, F. C. J. M. Wipff, G. Costero, A. Desreux, J. F. de Mendoza, J. Extraction and Selective Separation of Long-Lived Nuclides by Functionalized Macrocycles, European Commission, Nuclear Science and Technology series, EUR19605 EN 2000 p. 198. 

Both of the tetraaza[3.3.3.3]paracyclophane (1) and tetraaza[n.l.n.l]paracyclo-phane (n = 6, 7, 8 cf. 2) rings have frequently been used as fundamental molecular skeletons for preparation of functionalized macrocyclic hosts [24-36]. Formation of three-dimensionally extended hydrophobic cavities was approached by introducing multiple hydrocarbon branches into the macrocyclic skeletons. Multiple hydrophobic chains thus placed in a macrocycle must be extended in the same direction and undergo mutual association to attain their optimal hydrophobic interactions in aqueous media due to thermodynamic reasons, while in nonaqueous media they presumably assume a free and separated configuration to minimize their mutual steric interactions. Consequently, such hydrophobic branches may provide a large hydrophobic cavity in aqueous media. 

Dozol, J.E., Schwing-Weill, M.J., Amaud-Neu, F. et al. 2000. Extraction and selective separation of long-lived nuclides by functionalized macrocycles European Commission, Nuclear Science and Technology Report. EUR 19605. 

TOWARDS FUNCTIONAL MACROCYCLES SELF-ASSEMBLY AND TEMPLATE STRATEGIES... 

Template Strategies in the Synthesis of Functional Macrocycle Assemblies... 

Moyer, B. A., Bonnesen, P. V., Chambliss, C. K., Haverlock, T. J., Marchand, A. P., Chong, H.-S., McKim, A. S., Krishnudu, K., Ravikumar, K. S., Kumar, V. S., and Taklii, M. (2001) Use of cage-functionalized macrocycles and fluorinated alcohols in the liquid-liquid extraction of NaOH and other sodium salts, ACS Symposium Series, 778 (Nuclear Site Remediation), 114-132. 

G. D. Andreetti, A. Pochini, R. Ungaro, Molecular Inclusion in Functionalized Macrocycles. 6. The Crystal and Molecular-Structures of the Calix[4]arene from Para-(l,l,3,3-Tetramethylbutyl)Phenol and Its 1-1 Complex with Toluene. J. Chem. Soc. Perkin Trans II 1983, 1773-1779 G. D. Andreetti, F. Ugazzoli, in Calixarenes A Versatile Class ofMacrocyclic Compounds, J. Vicens and V. Bohmer, eds. Kluwer, Dordrecht, 1991. 

FUNCTIONALIZED MACROCYCLIC LIGANDS AS SENSORY MOLECULES FOR METAL IONS... 

FUNCTIONALIZED MACROCYCLIC LIGANDS AS SENSORY MOLECULES FOR METAL IONS Guoping Xue, Paul B. Savage, Jerald S. Bradshaw,... 

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