Stereoselection in the binding of Ln DOTA to γ-cyclodextrin: A near infrared circular dichroism study.

The formation of an inclusion complex between γ-cyclodextrin and Ln DOTA has been reported in the literature. All Ln DOTA complexes in solution give rise to a network of equilibria between different stereoisomers, which are pairs of enantiomers. By means of near infrared circular dichroism of the Yb derivative, we demonstrate that upon the formation of the host-guest complex, there is a complete stereoselection and that only the Λ(δδδδ) binds.