Geometrical manipulation of complex supramolecular tessellations by hierarchical assembly of amphiphilic platinum(II) complexes

Abstract

Here we report complex supramolecular tessellations achieved by the directed self-assembly of amphiphilic platinum(II) complexes. Despite the twofold symmetry, these geometrically simple molecules exhibit complicated structural hierarchy in a columnar manner. A possible key to such an order increase is the topological transition into circular trimers, which are noncovalently interlocked by metal···metal and π–π interactions, thereby allowing for cofacial stacking in a prismatic assembly. Another key to success is to use the immiscibility of the tailored hydrophobic and hydrophilic sidechains. Their phase separation leads to the formation of columnar crystalline nanostructures homogeneously oriented on the substrate, featuring an unusual geometry analogous to a rhombitrihexagonal Archimedean tiling. Furthermore, symmetry lowering of regular motifs by design results in an orthorhombic lattice obtained by the coassembly of two different platinum(II) amphiphiles. These findings illustrate the potentials of supramolecular engineering in creating complex self-assembled architectures of soft materials.

Anthracene-induced formation of highly twisted metallacycle and its crystal structure and tunable assembly behaviors

“…Inspired by assemblies in the natural world, researchers have created diverse suprastructures with distinct spatial arrangements via weak interactions, such as hydrogen bonds, aromatic stacking, and hydrophobic interactions (9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19). Among these, coordination-driven self-assembly (CDSA) provides a powerful strategy for producing metal organic complexes (MOCs) with various sizes, shapes, and metal/ligand stoichiometries (20)(21)(22)(23)(24)(25)(26). To date, diverse MOCs have been developed by coordination between metal ions and organic ligands, and these exhibit superiority over their precursors and can be used in emission units, sensors, and hosts as well as in applications in biomedical diagnosis and catalysis (27)(28)(29)(30)(31)(32)(33)(34).…”

Toward the Design and Construction of Supramolecular Functional Molecular Materials Based on Metal–Metal Interactions

“…Such an approach is still at its infancy and requires further exploration into the delicate control of the supramolecular assemblies in both the thermodynamics and kinetics aspects, so as to achieve interesting and unique morphologies via rational design strategies, ultimately leading to the systematic control and fine-tuning of distinctive nanoaggregates. Apart from building one-dimensional self-assembled and coassembled materials via the formation of directional Pt···Pt and π–π interactions, the utilization of Pt···Pt interactions in the formation of higher-dimensional supramolecular hierarchies would remain a major challenge for future advances. − Very recently, Yam and co-workers reported the design and construction of a two-dimensional (2D) multilayered supramolecular network with hexagonal packing through the use of a C 3 -symmetric alkynylplatinum­(II) complex, which led to the formation of a porous supramolecular polymer membrane with functionality. − Furthermore, the directional role of the noncovalent Pt···Pt interactions in the self-assembly process has been elucidated through a combination of experimental and computational efforts . The directional Pt···Pt interactions have been found to be arising from the interactions between the p z and d z 2 orbital pairs, playing an important role in governing the self-assembly processes and kinetics for achieving the formation of ordered self-assembled architectures in an anisotropic manner .…”

Supramolecular architectures based on binuclear Pt(ii) complexes consisting of different ligands and circular and helical fiber structures

“…35 Platinum(II) complexes of tridentate π-acceptor ligands are known to exhibit excellent spectroscopic properties and possess a high tendency to form supramolecular architectures by Pt⋯Pt and π-π interactions in the solid and solution states, owing to their square-planar structure. [36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53] Therefore, supramolecular architectures based on Pt(II) complexes have attracted much attention because of their intrinsically interesting physical properties and various morphologies of selfassembled architectures. For example, V. W.-W. Yam et al reported various morphologies of supramolecular aggregates based on mono-and binuclear platinum(II) complexes, such as helical fibers, and tubular and ribbon structures, and their spectroscopic properties.…”