Interaction of water-soluble triphenylphosphines with β-cyclodextrin: A quantum chemistry study

摘要

The interaction of β-cyclodextrin (β-CD) with meta-trisulfonated triphenylphosphine derivatives bearing one or two methyl (or methoxy) groups on the aromatic rings has been investigated by PM3 calculations. The results show that phosphine molecules interact with β-CD having either an unsubstituted sulfophenyl group or a substituted sulfophenyl group at the para and/or meta-position. The presence of one methyl or methoxy group in the ortho-position on each aromatic ring prevents the formation of an inclusion complex between meta-trisulfonated triphenylphosphine derivatives and β-CD. The deeply included phosphines in the β-CD cavity show significant van der Waals interactions with β-CD. These interactions are at the origin of the high association constants between these molecules and β-CD. Phosphines exhibiting small association constants interact with β-CD by forming H-bonds and weak (or null) van der Waals interactions.