Eight-membered and larger rings

The University of Akron, Akron, Ohio USA newkome uakron.edu 

As always, because of space limitations, only meso- and macrocycles possessing heteroatoms and/or subheterocyclic rings have been reviewed in general, lactones, lactams, and cyclic imides have been excluded. In view of the delayed availability of some articles appearing in previous years, several have been incorporated, where appropriate. I apologize in advance that it is impossible to do justice, to this topic and the numerous researchers that have elegantly contributed to the field, in the allotted twenty pages. 

The reversible acid-catalyzed transacetalation of the cyclophane formal 3 has been shown to undergo a ring-fusion/ring-fission process to generate a mixture of polymer cyclic formaldehyde acetals by means of oxonium ion intermediates 06CEJ8566 . The stepwise 

A methanofullerene derivative possessing an ammonium subunit has been prepared and subsequently shown to form a supramolecular complex with a porphyrin-crown ether conjugate 06T1979 . The synthesis and study of these fullerene-containing supramolecular photoactive devices have also been reported 06CRC1022 . 

Numerous reviews as well as perspectives, feature articles, tutorials, and mini-reviews have appeared throughout 2005 that are of particular interest to the macroheterocyclic enthusiast and those delving into supramolecular chemistry at the macromolecular level, as well as those studying nanoconstructs the chemistry and chiral properties of molecular knots 

The first new family of oxacyclophanes incorporating two 2,7-dioxafluorenone moieties connected by PEG units has been synthesized and structurally evaluated 05CEJ262 . The first 

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