β-Cyclodextrin-Glycerol Dimers: Synthesis and NMR Conformational Analysis

The synthesis of new -cyclodextrin dimers linked through their primary faces by different glycerol-like moieties by click chemistry is described. The unusual behaviour of these cyclodextringlycerol dimers in aqueous solution has been studied by NMR spectroscopy. We show that, depending on the length of the linking arm between the two cyclodextrins, the dimers could adopt very different conformations in water: symmetrical or pseudo[1]rotaxane-like structures through one D-glucopyranose unit tumbling in one -cyclodextrin.