The inclusion compound of a new ionizable derivative of β-cyclodextrin with ferrocenium drug

A new β-cyclodextrin (β-CD) derivative, mono[6 -deoxy-6-(2-butenedinitrile-2,3-dimercapto sodium salt)]-β- CD (6-β-CD), and its inclusion compound with a ferrocenium drug, have been prepared and characterized by IR, UV, ¹³C-NMR spectroscopy, and mass spectrometry, elemental analysis, thermogravimetry, and cyclic voltammetry (CV). The interplay between the side-arm anion of β-CD and the ferrocenium (guest) in the inclusion compound 6-mnt-β-CD^-/Fc⁺ has been investigated by ¹³C-NMR, UV, IR, and thermogravimetric methods. Charge transfer from the anion to the cation in 6-mnt-β- CD^-/Fc⁺ was then experimentally identified. The interaction between the guest and the host with side-arm in 6-mnt- β-CD^-/Fc⁺ resulted in smaller positive potential shifts compared to that in the inclusion compound [β-CD/Fc⁺]BF₄^-.