Liu Y.
Lawrence Berkeley National Laboratory, US
Keywords: coordination, cyclodextrin, macrocycle, [2]catenane
Here we describe our findings on the facile preparation of first [2]catenanes from metal-ligand coordination macrocycles and b-CD ring. The [2]catenane formation is illustrated in Figure 1. Coordination between a divalent ligand and Pd(II) spontaneously gives rise to a macrocycle. This macrocycle is able to interlock with b-CD as a result of the hydrophobic interaction between the divalent ligand and b-CD ring. The complexation between the two ring components undergoes dynamic equilibrium in solution. The catenane formation was illustrated by various 1H NMR spectroscopic methods and UV-vis spectroscopic methods. By changing the metal center from Pd(II) to Pt(II), the dynamic nature of the [2]catenanes was altered to a “locked” one because the Pt(II)-pyridine coordination bond is irreversible (“locked”) under ordinary conditions in contrast to the reversible Pd(II)-pyridine bond. The reported method provides an extremely simple and highly efficient approach in generating [2]catenanes from readily available starting materials. Such findings will be extended towards the development of higher order polymers and switchable devices with embedded b-CD units.
Journal: TechConnect Briefs
Volume: 4, Technical Proceedings of the 2007 NSTI Nanotechnology Conference and Trade Show, Volume 4
Published: May 20, 2007
Pages: 206 - 209
Industry sector: Advanced Materials & Manufacturing
Topic: Nanoparticle Synthesis & Applications
ISBN: 1-4200-6376-6