One-, Two-, and Three-Dimensional Supramolecular Assemblies Based on Tubular and Regular Polygonal Structures of Pillar[ n ]arenes

Abstract

Pillar[ n]arenes, which were first reported by our group in 2008, are promising macrocyclic compounds in supramolecular chemistry. The simple, tubular, and highly symmetrical shape of pillar[ n]arenes has allowed various supramolecular assemblies with well-defined structures to be constructed. The pillar-shaped structures of pillar[ n]arenes are suitable for surface modification and formation of one-dimensional (1D) channels. The regular polygonal prism shape of organized pillar[ n]arenes contributes to the construction of highly assembled structures such as two-dimensional (2D) sheets and three-dimensional (3D) spheres. In this minireview, we describe supramolecular assemblies with various dimensions. First, we discuss 1D supramolecular assemblies based on tubular structures of pillar[ n]arenes. Second, 2D supramolecular sheet formation based on regular polygonal structures is described. Finally, 3D supramolecular assemblies such as vesicles and 3D frameworks constructed from pillar[ n]arenes are discussed.

Supramolecular Chiral 2D Materials and Emerging Functions

“…For example, the devel opment of the pillar[n]arenes with a permanent pore provides a platform to construct 2D architectures with various func tions via tuning interaction between pillar[n]arenes and guest molecules. [39] In the case of pillar [6]arene P[6]1, when some hydroquinone units of P [6]1 were oxidized to benzoquinones, the formation of chargetransfer complexes would induce a sidebyside arrangement and form hexagonal dense packing of p[6]1. [40] In the presence of polyoxometalate (POM), the porous sheets were observed from the selfassembly of imidazolium functionalized pillar [6]arene P [6]2.…”

“…Rigid molecules with macrocyclic topology can provide appropriate building blocks for construction of 2D sheet structures through noncovalent interactions. For example, the development of the pillar[ n ]arenes with a permanent pore provides a platform to construct 2D architectures with various functions via tuning interaction between pillar[ n ]arenes and guest molecules . In the case of pillar[6]arene P[6]1, when some hydroquinone units of P[6]1 were oxidized to benzoquinones, the formation of charge‐transfer complexes would induce a side‐by‐side arrangement and form hexagonal dense packing of p[6]1 .…”

Multidentate Anchors for Surface Functionalization

“…The Au/CB[7] SAMs could be further functionalized by host‐guest interaction, e.g., by incorporation of ferrocene into the cavity of immobilized CB[7] molecules. This strategy has been used to prepare a number of metal electrode surfaces and nanoparticles for applications in catalysis, sensing, and drug delivery, which have been the topic of some recent reviews and will not be further discussed here.…”

Towards Universal Stimuli-Responsive Drug Delivery Systems: Pillar[5]arenes Synthesis and Self-Assembly into Nanocontainers with Tetrazole Polymers

“…To address the problem, it was proposed to use various multifunctional macrocyclic compounds capable of controlled interaction with the polymer, which leads to the formation of stable associates in water [ 12 ]. Today, the most promising macrocyclic compounds are representatives of a new class of para-cyclophanes—pillar[n]arenes [ 13 , 14 , 15 ]. Pillar[n]arenes are macrocyclic compounds in which fragments of substituted hydroquinones are interconnected by methylene bridges [ 13 ].…”