Building on architectural principles for three-dimensional metallosupramolecular construction

Abstract

Over the last two decades the field of metallosupramolecular self-assembly has emerged as a promising research area for the development of intricate, three-dimensional structures of increasing complexity and functionality. The advent of this area of research has strongly benefited from design principles that considered the ligand geometry and metal coordination geometry, thus opening up routes towards rationally designed classical (Archimedean or Platonic) architectures. In this tutorial review, we will focus on more recent developments in the design and synthesis of three-dimensional suprastructures which have non-classical architectures (non-Archimedean/Platonic solids) and we will explicitly address the secondary effects responsible for their formation. Three classes of metallosupramolecular assemblies will be discussed: architectures formed through the combination of a single ligand and metal, heteroleptic structures and heterometallic structures. It is hoped that our exposition may suggest how different principles employed in these three classes of structures might be combined to create even greater complexity and potential for function.

Lanthanide coordination polymers with pyridyl-N-oxide or carboxylate functionalised host ligands

“…Pyridyl N-Ag and (B)H-Ag bond lengths were measured at 2.264(4), 2.280(4) and 2.176 Å, respectively, alongside N-Ag-N bond angles of 127.48 (14), 101.76 (14) and 97.97(13)°. This is contrasting behaviour to that observed for complex 1m, where silver(I) centres were coordinated by four pyridyl donors and the [Co(C 2 B 9 H 11 ) 2 ] -anion remained uncoordinated, Figure 1b.…”

“…[11][12][13] The study of sterically and interactionally similar ligand sets has garnered much interest due to their ability to selectively form homo-and heteroleptic complexes, allowing the formation of structures ordinarily inaccessible with a single ligand system. [14][15][16] This phenomenon relies on a sliding scale of kinetic stability, whereby the dynamic nature of the coordination bond can be either exploited to enable ligand exchange, or relied upon for kinetic stability. 17 The tailoring of organic ligands and assembly conditions allows the chemist to exercise a degree of control over their self-assembly.…”

Self-assembly of a M4L6 complex with unexpected S4 symmetry

“…One of the most recent developments in supramolecular chemistry [1][2][3][4] is the utilization of subcomponent self-assembly in which structures are generated in situ from their, often simple, subcomponents. [5][6][7] This still immature field allows the construction of complex 3D structures [8][9][10][11] through spontaneous and hierarchical assembly by means of chemical reactions and weak intermolecular interactions. When one of the components are metal ions, the molecular architecture of these self-assembled 3D objects heavily depends on the nature of the coordination geometry of the metal ion used.…”

Photoinduced transformations of stiff-stilbene-based discrete metallacycles to metallosupramolecular polymers

“…Yang and coworkers (8) reported hydrogen-bonded supramolecular polymers and studied their polymerization mechanisms and physical properties based on the photoisomerization of the stiff-stilbene units. Nevertheless, stiff-stilbene-based supramolecular entities are underexplored despite exhibiting properties that make the functionality potentially useful in the construction of photoresponsive supramolecular materials.Coordination-driven self-assembly is a powerful method of constructing supramolecular coordination complexes (SCCs) by the spontaneous formation of metal-ligand bonds that draws inspiration from the design principles of natural systems (9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). This approach organizes metal acceptors and organic donors to prepare well-defined cavity-cored 2D metallacycles and 3D metallacages, which can be functionalized on their interior or exterior vertices for applications in host-guest chemistry (21, 22), catalysis (23), molecular flasks (24), bioengineering (25), amphiphilic self-assembly (26), and so on.…”