Five discrete multinuclear metal-organic assemblies from one ligand: deciphering the effects of different templates

A rigid organic ligand, formed through the subcomponent self-assembly of p-toluidine and 6,6′-diformyl-3,3′-bipyridine, was employed in a systematic investigation into the synergistic and competing effects of metal and anion templation. A range of discrete and polymeric metal-organic complexes were formed, many of which represent structure types that have not previously been observed and whose formation would not be predicted on taking into account solely geometric considerations. These complex structures, capable of binding multiple guests within individual binding pockets, were characterized by NMR, ESI-MS, and single-crystal X-ray diffraction. The factors that stabilize individual complexes and lead to the formation of one over another are discussed.