Directing Organometallic\nRing–Chain Equilibrium\nby Electrostatic Interactions

Dynamic chemistry, which falls into the realm of both\nsupramolecular\nand covalent chemistry, enables intriguing properties, such as structural\ndiversity, self-healing, and adaptability. Due to robustness of covalent\nbonds compared to noncovalent ones, dynamic covalent chemistry has\nbeen exploited to synthesize complex molecular nanostructures at solid/liquid\ninterfaces under ambient conditions, generally responsive to internal\nfactors that directly regulate intermolecular covalent bonds. However,\ndirecting dynamics of covalent nanostructures, <i>e.g</i>., the typical ring–chain equilibria, on surface by extrinsic\ninteractions remains elusive and challenging. Herein, we have controllably\ndirected the ring–chain equilibrium of covalent organometallic\nstructures by regulating intermolecular electrostatic interactions,\nthus achieving on-surface dynamic covalent chemistry under ultrahigh\nvacuum conditions. Our findings unravel the dynamic mechanism of covalent\npolymers governed by weak intermolecular interactions at the submolecular\nlevel, which not only bridges the gap between supramolecular and covalent\nchemistry but also offers great opportunities for the fabrication\nof adaptive polymeric nanostructures that respond to different conditions.