Supramolecular encapsulation of C60 in a water soluble calixarene; A core‐shell charge transfer complex

A calix[8]arene derivative has been found to form a water soluble complex with fullerene‐C60, but not with C70, which allows extraction of C60 from e.g. toluene into the aqueous phase. Charge transfer character of the complex is evident from strong charge transfer absorption around 440 nm measured in water. Molecular modeling calculations indicate a core‐shell structure for the complex.