Discrete 1 : 1 complexes and higher order assemblies formed from aminobenzene sulphonate anions and a tetraimidazolium "molecular box".

Use of isomeric aminobenzene sulphonate anions in conjunction with a tetraimidazolium "molecular box" leads to self-assembled embedded structures. Simple 1 : 1 complexes are formed at low concentrations in DMSO when the host : guest ratio is 1.0. Higher order species are seen as the concentration is increased or the host-guest ratio is perturbed. The assembly and disassembly of the supramolecular aggregates can be controlled by application of various external stimuli, including changes in concentration, temperature, and protonation state of the guest species.