Self-organization by selection: generation of a metallosupramolecular grid architecture by selection of components in a dynamic library of ligands.
Self-organization by selection is implemented in the generation of a tetranuclear [2 x 2] grid-type metallosupramolecular architecture from its components. It occurs through a two-level self-assembly involving two dynamic processes: reversible covalent bound connection and reversible metal ion coordination. Thus, mixing the aminophenol 3, the dialdehyde 4, and zinc acetate generates the grid complex 1a(Zn) via the assembly of the ligand 2a by imine formation and of the grid by zinc(II) binding. When the same process is conducted in a solution containing a mixture of different aminophenol and carbonyl components, the generation of the grid 1a(Zn) drives the selection of the correct components in a virtual dynamic library of ligands, displaying an amplification factor of >100 and a selectivity of >99%. Component exchange as well as reversible protonic modulation of the assembly/disassembly process display the dynamic character of the system and its ability to respond/adapt to changes in environmental conditions. The processes described demonstrate the implementation of a two-level self-organization by selection operating on the dynamic diversity generated by a set of reversibly connected components and driven by the formation of a specific product in a "self-design" fashion.