Synthesis and properties of helically-folded poly(arylenediethynylene)s

Three arylenediethnylene-based helical foldamers having pyridine, naphthaleneimide and pyrene cores show unique conformational changes and photophysical properties in various organic solvents.

Optically active Ag(i): o-OPE helicates using a single homochiral sulfoxide as chiral inducer

In this work we describe the ability of a simple enantiopure sulfoxide group to promote folding of oligo ortho-phenylene ethynylenes (o-OPEs) with one helical sense. A family of foldamers with up to seven triple bonds was synthesized and fully characterized. Moreover, changes in structure and chiroptical properties caused by Ag(i) coordination have been studied by NMR, UV, VCD and ECD measurements. Quantum mechanical DFT calculations support experimental results.

Making Molecular and Macromolecular Helical Tubes: Covalent and Noncovalent Approaches

Aromatic foldamers possess well-defined cavity that can be stabilized by discrete intramolecular interactions including hydrogen bonding, solvophobicity, electrostatic repulsion, or coordination. Long foldamers can form dynamic deep helical tubular architectures that are not only structurally attractive but also useful hosts for guest encapsulation, chirality induction, delivery, and catalysis. This kind of helical tubular structures can be formed by single molecules or macromolecules or by connecting short-folded or helical segments through noncovalent or covalent forces. This perspective summarizes the recent advances on the construction of helical tubes and their properties and functions.

Allosteric regulation of metal-binding sites inside an optically-active helical foldamer and its tubular assemblies

A helical foldamer bearing metal-binding linker units self-assembles into helical nanofibers that undergo a reversible helix-to-helix transition upon the binding and release of Ag(i) ions.

Supramolecular Helical Systems: Helical Assemblies of Small Molecules, Foldamers, and Polymers with Chiral Amplification and Their Functions

In this review, we describe the recent advances in supramolecular helical assemblies formed from chiral and achiral small molecules, oligomers (foldamers), and helical and nonhelical polymers from the viewpoints of their formations with unique chiral phenomena, such as amplification of chirality during the dynamic helically assembled processes, properties, and specific functionalities, some of which have not been observed in or achieved by biological systems. In addition, a brief historical overview of the helical assemblies of small molecules and remarkable progress in the synthesis of single-stranded and multistranded helical foldamers and polymers, their properties, structures, and functions, mainly since 2009, will also be described.