Synthesis and complexation of polytopic adamantane-based probes

The complexation of adamantane derivatives with cyclodextrins has been the subject of numerous studies during the last twenty years.1-18 This is due to several reasons. First, adamantane derivatives form strong complexes with β-cyclodextrin and the equlibrium constants are the strongest which can be found for the formation of this kind of inclusion complexes. This is because of the adamantyl residue perfectly fits inside the β-cyclodextrin cavity since the radios of this residue is slightly larger thant the radius inside the cavity available for guest in this cyclodextrin. Second, unimers simultaneously having guest (adamantyl residue) and host (β-cyclodextrin residue) moieties in their structure have been obtained and by self-association formed linear supramolecular structure. Third, adamantyl dimers have been synthesized and complexed with β-cyclodextrin dimers to form the so called “chelate complexes”. Fourth, adamantyl dimers have used to obtain linear and dentritic-like supramolecular polymers when they are complexed with polytopic hosts derived from β-cyclodextrin. Finally, polytopic hosts and polytopic guests can be used to form other macromolecular assemblies. In such cases, high viscosity enhancements have been observed, which are maximum for a composition in which the stoichiometry is one host (βCD residue):one guest (adamantyl residue). Thus the synthesis of both polytopic hosts and guests have a growing importance in designing new supramolecular entities mainly supramolecular polymers. The aim of this paper is the synthesis of adamantyl oligomers (dimers and trimers) which can later be used as polytopic guests.