Stable pillar[5]arene‐containing [2]rotaxane building blocks with pentafluorophenyl ester stoppers have been efficiently prepared on a multi‐gram scale. Reaction of these building blocks with various nucleophiles gave access to a wide range of [2]rotaxanes with amide, ester or thioester stoppers in good to excellent yields. The rotaxane structure is fully preserved during these chemical transformations. Actually, the addition‐elimination mechanism at work during these transformations totally prevents the unthreading of the axle moiety of the mechanically interlocked system. The stopper exchange reactions were optimized both in solution and under mechanochemical solvent‐free conditions. While amide formation is more efficient in solution, the solvent‐free conditions are more powerful for the transesterification reactions. Starting from a fullerene‐functionalized pillar[5]arene derivative, this new strategy gave easy access to a photoactive [2]rotaxane incorporating a C60 moiety and two Bodipy stoppers. Despite the absence of covalent connectivity between the Bodipy and the fullerene moieties in this photoactive molecular device, efficient through‐space excited state interactions have been evidenced in this rotaxane.

With their ten peripheral substituents, pillar[5]arenes are attractive compact scaffolds for the construction of nanomaterials with a controlled number of functional groups distributed around the macrocyclic core. This review paper is focused on the functionalization of pillar[5]arene derivatives with small dendrons to generate dendrimer-like nanomaterials and bioactive compounds. Examples include non-viral gene vectors, bioactive glycoclusters, and liquid-crystalline materials.

Rotaxane building blocks with pentafluorophenyl ester stoppers have been efficiently prepared and their treatment with various nucleophiles provided a wide range of rotaxanes with amide, ester or thioester stoppers. This new strategy also gave easy access to a photoactive rotaxane incorporating a fulleropillar[5]arene moiety and two Bodipy stoppers. Despite the absence of covalent connectivity between the Bodipy subunits and the fullerene, efficient through space excited state interactions have been evidenced in this rotaxane. More information can be found in the Full Paper by J.‐F. Nierengarten et al. (DOI: 10.1002/chem.202100943).