Platinamacrocycles containing 2,5-thiophenediyl and poly(2,5-thiophenediyl)-linked azaaromatic ligands: new structural paradigms for metallosupramolecular chemistry

The synthesis and characterization of 10 ditopic ligands containing pyridine, quinoline or acridine metal-binding domains linked by 2,5-thiophenediyl or poly(2,5-thiophenediyl) spacers are reported. The single crystal structures of 2,5-bis(4-pyridyl)thiophene (1), 2,5-bis(9-acridinyl)thiophene (VI), 5,5`-bis(4-quinolyl)-2,2`-bithiophene (IX), and 5-(9-acridinyl)-5`-(4-pyridyl)-2,2`-bithiophene (X) have been determined. The reactions of the ligands with cis-[Pt(PEt3)(2)(OTf)(2)] lead to the formation of families of platinamacrocycles. The preferences for a particular [n+n] metallomacrocycle for a given heterocyclic ligand are explored in terms of the flexibility of the ligand.