Phenanthroline- and Terpyridine-Substituted Tetralactam Macrocycles: A Facile Route to Rigid Di- and Trivalent Receptors and Interlocked Molecules

Bromo-substituted Hunter/Vogtle-type tetralactam macrocycles (TLMs) represent key intermediates for the attachment of terpyridyl and phenanthroline metal binding sites through cross-coupling reactions. From these monovalent precursors, metal complexes can easily be obtained that present the macrocycles in a multivalent fashion. Depending on the nature of the metal ion, the properties of the complexes can be tuned with respect to valency (e.g., phen-TLM + CuI: divalent, phen-TLM + FeII: trivalent) and lability against TLM ligand exchange (e.g., CuI: slow, but reversible exchange, RuIICl2: kinetically inert).