No abstract

To explore a new supramolecular interaction as the main driving force to induce hierarchical self-assembly (HSA) is of great importance in supramolecular chemistry. Herein, we present a radical-induced HSA process through the construction of well-defined rhomboidal metallacycles containing triphenylamine (TPA) moieties. The light-induced radical generation of the TPA-based metallacycle has been demonstrated, which was found to subsequently drive hierarchical selfassembly of metallacycles in both solution and solid states. The morphologies of nanovesicle structures and nanospheres resulting from hierarchical self-assembly have been well-illustrated by using TEM and high-angle annular dark-field STEM (HAADF-STEM) micrographs. The mechanism of HSA is supposed to be associated with the TPA radical interaction and metallacycle stacking interaction, which has been supported by the coarse-grained molecular dynamics simulations. This study provides important information to understand the fundamental TPA radical interaction, which thus injects new energy into the hierarchical self-assembly of supramolecular coordination complexes (SCCs). More interestingly, the stability of TPA radical cations was significantly increased in these metallacycles during the hierarchical self-assembly process, thereby opening a new way to develop stable organic radical cations in the future.

Well-defined discrete metal-organic cages have been widely explored in the field of supramolecular catalysis. However, these metal-organic cages have been rarely explored as heterogeneous catalysts for one-pot reactions. Herein, we present the first successful confinement self-assembly of (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO)containing metal-organic cages within amino-functionalized mesoporous carbon to realize a new family of bifunctional heterogeneous catalyst (Cage@FDU-ED) for one-pot reactions. The orthogonal features of the isolated catalytically active sites within the obtained bifunctional catalyst lead to enhanced catalytic activities, selectivity, and recyclability with the overall transformation yielding up to 96% conversion. These results demonstrate that continuous chemical transformation with high efficiency is possible through careful design of catalytic sites in both metal-organic cages and mesoporous matrix isolatedly. This study paves a new way toward metal-organic cages as a promising platform for heterogeneous sequential reactions.

No abstract