Self-Assembly of the First Fullerene-Containing[2]Catenane (original) (raw)

1997, Angewandte Chemie International Edition in English

Since fullerenes became available ['] in macroscopic quantities during the 1990s, a wide range of chemical transformations involving these novel carbon allotropes have been developed.[31 In the last few years chemists have also exploited noncovalent bonding interactions to self-assemble["] a number of interlocked molecules-principally catenanes and rotaxanes[51-that display fascinating topological features.r61 The unique electronic properties of C,,, for example its strong electronaccepting capabilitie~,[~] make it an attractive candidate for incorporation into r~taxanes['~ and catenanes. We now report the self-assembly of the first C,,-containing catenane, thus signaling completion of the initial merger between these two contemporary areas of chemistry. Recently the Zurich wing of this collaborative venture describedL8] a regio-and diastereoselective bisfunctionalization of C,, based on cyclization of the carbon sphere with bis(ma1onate) derivatives in a double Bingelrgl addition. Here we underline the versatility of this method by fusing bis(p-phenylene)-[34]crown-10 (1) , which has two n electron rich hydroquinone rings, to C,, in a regioselective manner. Thereafter, we describe the template-directed formation of cyclobis(paraquat-p-phenylene) [lo] around the C,,-appended macrocyclic polyether to give the [2]catenane, an exotic molecular compound featuring an unusual topology and sporting undeniable aesthetic appeal.