Dissipative formation of a transient foldaxane with a fuel-like thread†

Abstract

Transient assemblies generated by fuel consuming biomacromolecules are essential for biological processes. Although artificial transient assemblies have been investigated extensively in recent years, molecules mimicking secondary structures of biomacromolecules have been rarely exploited to construct fuel driven transient systems. Herein, we report a transient foldaxane system using a double helical aromatic oligoamide. The aromatic oligoamide adopts a mixture of parallel and antiparallel conformations in solution, while the presence of a molecular thread drives the conversion of the parallel double helix to an antiparallel double helix and the formation of a foldaxane between the antiparallel double helix and the thread. 4-Methylpiperidine can cleave the thread and generate a foldaxane containing a parallel double helix and the cleaved thread. The formation of an antiparallel foldaxane can be fueled with this thread for up to three cycles. These results open up a possibility of introducing dissipative behavior into abiotic quaternary structures to generate life-like dynamic systems.