Synthesis of water-soluble 2-alkylcyclodextrin–C60 conjugates and their inclusion complexation in aqueous solution

Two β-cyclodextrin–C60 conjugates ( and ) with a flexible linker at the secondary face of cyclodextrin are synthesized by a single reaction of 2-(ω-azidoundecanyl)-2-O-heptakis (2,3,6-tri-O-methyl)-β-cyclodextrin () and C60, both of which display satisfactory water solubility. Structural analyses show that is a closed [5,6] aziridinofullerene, whereas is a bis-adduct derivative. Using rhodamine B (RhB) as a guest molecule, the inclusion complexation behavior of was investigated in aqueous solution.