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.