The hitherto longest molecular thread-belt assemblies 8 , 29 , 32 and 43 based on benzene-connected [3.3]metacyclophane units were prepared by means of a repetitive synthetic method. The preparation of difunctionalized [3.3]metacyclophane units (14 , 22 , 26) succeeded in good yields by an iteration sequence including the cyclization to the cyclophane skeleton and the derivatization of the ester groups. The covalent linkage of the [3.3]metacyclophane belt parts to the thread part leads to higher product yields compared to cyclophane belts only. The final intermolecular macrocyclizations are done by reaction of diamide, dithiol or dibromide functionalized belt fragments to obtain a minimum of single bridged benzene units in the macrocyclic thread-belt assemblies (ÒpseudobeltsÓ).
The first syntheses of a tetrakis(rotaxane) and a bis(pretzelane) in good yields are reported. To achieve this an extended durene-based spacered tetrabromide is linked covalently to a new monosulfonamide rotaxane and a bis(sulfonamide) catenane. This catenane was isolable simply through recrystallization. The bis(pretzelane) represents a new intertwined molecular architecture.
Key indicatorsSingle-crystal X-ray study T = 123 K Mean (C-C) = 0.002 Å R factor = 0.033 wR factor = 0.093 Data-to-parameter ratio = 14.6For details of how these key indicators were automatically derived from the article, see
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