Syntheses and structural aspects of cyclodextrin/dialkylamine inclusion compounds

We report the syntheses and structural aspects of cyclodextrin host-guest inclusion compounds containing linear secondary alkylamines (dipropyl, dibutyl, dipentyl, dihexyl, and dioctyl) at 25 degrees C. Elemental analysis, C-13 CP-MAS NMR spectroscopy, and powder X-ray diffraction analysis confirm the inclusion process, The basic host structure of the products is similar to that of typical cyclodextrin inclusion systems. C-13 MAS NMR experiments show a different resonance pattern for the confined guest molecules with respect to the amine in the liquid phase. The presence of different resonance signals for the homologous carbon atoms of both dialkylamine branches is evidence for the non-symmetric location of the amine in the cyclodextrin channels.