Synthesis of rotaxane assemblies

The preparative syntheses of new nano-sized rotaxane assemblies are described, namely, of the first tris[2]rotaxane, 15, the first bis[2]rotaxane connected al the axles, 4, and the first [3]rotaxane with two different axles, 12 (unsymmetrical ''bis[2]rotaxane''). These syntheses were made possible by the directed incorporation of a sulfonamide group into the amide-linked rotaxane building blocks, The sulfonamide moiety can be used as a functional group in alkylation reactions, allowing the further attachment of building blocks in good yields, The successful synthesis of these new rotaxane architectures demonstrates the synthetic potential of this sulfonamide strategy in the preparation of multirotaxane and dendritic rotaxane structures.