Functional, discrete, nanoscale supramolecular assemblies

The last decade has witnessed an unprecedented pursuit of discrete, nanoscale supramolecular aggregates, built by modern methods of self-assembly strategies. Several efficient new synthetic methods have been developed for engineering spectacular multicomponent supramolecular aggregates. Amongst all the techniques explored, metal coordination and hydrogen-bonding motifs are the most celebrated means of producing structurally rich supramolecular architectures. While a truly biomimetic approach would typically employ a balanced mixture of weak interactions (hydrogen-bonding, pi-pi interactions, etc.), stronger non-covalent interactions (such as the coordinative metal ligand bond) have equally proven their high utility in the preparation of nanoscale assemblies. The time has now come to install functional elements to nanoscale aggregates in order to build nanoscale devices that exhibit non-linearity, interdependence and emergence, i.e. typical characteristics of more complex systems. Currently, functional model designing is still in its early stages, and lags far behind the progress made in structural engineering. Hence, in the present article some recent advances in the structural design of nanoscale assemblies are shown, along with examples from the following areas: supramolecular catalysis, photoactive assemblies, molecular recognition and switches, and electroactive assemblies.