Calix[4]benzocrown-[60]fullerene dyads: synthesis and complexation properties for dyes

摘要

Two novel calix[4]benzocrown-[60]fullerene dyads were obtained by refluxing calix[4]benzocrown derivative containing formacyl group with sarcosine or glycine and C60 in toluene at reflux via 1,3-dipolar cycloaddition of azomethine ylides tied to C60 in the yields of 30 and 28 %, respectively. Their structures and conformations were characterized by UV–Vis, 1H NMR, ESI–MS, elemental analysis. Their complexation properties for four dyes were studied by liquid–liquid extraction experiments, complexation UV–Vis spectroscopy and complexation ESI–MS spectroscopy. The results of liquid–liquid extraction suggested that they exhibited excellent extraction abilities towards the four test dyes with the extraction percentages fluctuating in the scope of 75–90 %. The complexation UV–Vis spectra showed the 1:1 complexes between hosts and guests in DMSO solution. The association constants were as high as 5.40 × 104–1.05 × 106 M−1. The formation of 1:1 complex was further confirmed by the complexation ESI–MS spectrum of compound 4a for Neutral red in DMSO solution. These complexation experiments implied that the novel calix[4]benzocrown-[60]fullerene dyads possess excellent complexation abilities for organic dyes.