Preparation of macrocyclon analogues: calix[8]arenes with extended polyethylene glycol chains

A one-pot methodology has been developed for the preparation of macrocyclon mimics, i.e., calix[8]arenes containing hydrophobic alkyl substituents on the upper rim and hydrophilic polyethylene glycol chains on the lower rim. Compounds containing PEG chains of up to 24 repeating ethylene oxide (EO) units can be prepared. With increasing molecular weight, these amphiphilic compounds can be classified as macromolecules, and can be difficult to characterise as single molecules. The limitations of conventional analytical techniques are discussed. (c) 2007 Elsevier Ltd. All rights reserved.