Metallo-Controlled Dynamic Molecular Tweezers: Design, Synthesis, and Self-Assembly by Metal-Ion Coordination

Abstract

The introduction of controllable dynamic features into synthetic receptors represents a step towards “smart” adaptive nanodevices. We report herein our studies on the construction of dynamic molecular tweezers in which the binding of a substrate is allosterically controlled through shape switching of the receptor induced by metal-ion coordination. 1D, 2D NMR spectroscopy and X-ray crystallography were used to identify the nature of the metallosupramolecular entity generated. The presence of large aromatic naphthalene diimide moieties on the scaffold of the molecular tweezers strongly influences their coordination-driven self-assembly. It was found that these additional stacking interactions lead to the cooperative formation of a homocomplex, to the self-sorted assembly of a hetero complex, and to the binding of non-coordinating aromatic guests.