Hierarchical self-assembly of amphiphilic metallohosts to give discrete nanostructures.

The synthesis and aggregation behavior of a new class of rigid metallohosts is described. The molecules consist of a ruthenium-bipyridine complex functionalized with a glycoluril-based receptor cavity. By specific molecular recognition processes in water, the metallohosts self-assemble to form large arrays of molecules. Depending on the size of the cavity side walls of the host, these arrays can grow in a hierarchical process into discrete rectangular and cigar-like aggregates of nanometer size, which can be visualized by electron microscopy.