Reversible Conformational Changes and Metal Coordination Allow the Controlled Self-assembly of Aromatic Amides

Singleton, Michael L. [UCL]

Orthogonal assembly in biological systems is essential for mediating the myriad complex interactions and biological processes necessary for life. Reaching this level of complexity with purely synthetic systems remains a valuable goal in chemistry but is generally limited by the handful of compatible interactions that can be included on small molecules. The use of folded oligomers that can selectively interact with each other could provide a nearly endless supply of directional building blocks for self-assembly that can be made orthogonal to each other through simple sequence modification. Specifically, exploiting the multiple helix forming properties of some aromatic foldamers for this purpose could lead to new abiotic tools for precisely controlling self-assembly over large size regimes. To this end, our group is interested in how aromatic oligoamides can be used as tools for orthogonal self-assembly of larger structures, Figure 1. This communication describes two approaches for controlling self-assembly with aromatic oligoamides based on A) the incorporation of specific metal binding sites into oligomers to allow formation of diverse metal-organic architectures and B) directing large-scale structural changes with a Diels-Alder/retro-Diels-Alder strategy that allows stimuli responsive hybridization. The properties of these systems and their potential as orthogonal building blocks for controlled self-assembly will be discussed.