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

Two beta-cyclodextrin-C-60 conjugates (3 and 4) with a flexible linker at the secondary face of cyclodextrin are synthesized by a single reaction of 2-(omega-azidoundecanyl)-2-O-heptakis (2,3,6-tri-O-methyl)-beta-cyclodextrin (2) and C-60, both of which display satisfactory water solubility. Structural analyses show that 3 is a closed [5,6] aziridinofullerene, whereas 4 is a bis-adduct derivative. Using rhodamine B (RhB) as a guest molecule, the inclusion complexation behavior of 3 was investigated in aqueous solution. (c) 2005 Elsevier Ltd. All rights reserved.