Hosting Various Guests Including Fullerenes and Free Radicals in Versatile Organic Paramagnetic <b>bTbk</b> Open Frameworks

The dinitroxide bis­(TEMPO) bisketal (<b>bTbk</b>) was shown to crystallize into open frameworks whose structures were determined by single-crystal X-ray diffraction. We show that <b>bTbk</b> can be used as a supramolecular building block for the hosting of a plethora of guests inside the 1D channels of its paramagnetic framework, including other radicals such as TEMPO or 2-azaadamantane-<i>N</i>-oxyl. C₆₀ and C₇₀ were also found to be easily included in this open framework during its crystallization. This resulted in well-defined, nanostructured assemblies of composite radical crystals (<b>bTbk</b>/toluene/C₆₀ or C₇₀) or (<b>bTbk</b>/toluene/TEMPO) by a very simple dissolution/crystallization process with tunable guest content. Selective C₆₀ extraction was also demonstrated directly from fullerene soot