Quadruple n Stack of Two Perylene Bisimide Tweezers: A Bimolecular Complex with Kinetic Stability

摘要

Self-assembly has become an attractive approach towards functional materials. However, to match with covalent chemistry, self-assembly processes have to be developed from reversible thermodynamic regimes to systems of kinetic stability. Generally, the weak supramolecular interactions such as hydrogen-bonding and π-π stacking rarely provide sufficient binding strength to lock particular structures in a desired architecture. Accordingly, examples of kinetically stable supramolecular structures are given either for large but structurally less defined aggregates or discrete self-assemblies that are attainable by using multiple intermolec-ular interactions or stronger metal ion-ligand interactions the latter represent a borderline case between covalent and noncovalent chemistry. In our recent work on perylene bisimide (PBI) dyes, we realized that PBI-PBI interactions are stronger than those of any other π-π stacking interactions reported for other π scaffolds, for example, hexabenzocoronenes, phthalocyanines. phenylacetylene mac-rocycles, and naphthalene bisimides.' Thus, we envisioned that the formation of discrete well-defined and kinetically persistent PBI aggregates might be feasible for self-assemblies of rather modest size.