One and Two-dimensional NMR Investigations of the Inclusion of the Monosulfonated Triphenylphosphine in the β-cyclodextrin
Résumé
The interaction between the sodium salt of the monosulfonated triphenylphosphine and the g -cyclodextrin has been investigated in aqueous solution by high field nuclear magnetic resonance and UV-Vis spectroscopies. Continuous variation and titration plots obtained from NMR and UV-Vis data indicate formation of a 1:1 inclusion complex and allow to calculate an association constant of 12,000 M m 1 at 25C. The T-ROESY NMR experiments complemented by molecular modelling suggest that one of non-sulfonated aromatic rings is included into the hydrophobic cavity of the g -cyclodextrin from the side of secondary hydroxyl groups. Formation of inclusion complex with the f - and n -cyclodextrin is also briefly discussed.