Spin-Labelled Pillar[5]arene as Paramagnetic Host for Supramolecular Assemblies

The synthesis and characterization of a new member of the pillar[5]arene family carrying a paramagnetic side-arm based on the 2,2,6,6-tetramethylpiperidine N-oxide (TEMPO) moiety has been achieved by the Huisgen-type CuAAC reaction. The possibility of exploiting the proposed pillar[5]arene as a host in paramagnetic rotaxane-like structures was tested in the presence of charged guests and confirmed by NMR spectroscopy.