Heterotopic Assemblage of Two Different Disk-Shaped Ligands through Trinuclear Silver(l) Complexation: Ligand Exchange-Driven Molecular Motion

摘要

The sandwich-shaped heterotopic trinuclear Ag~+ complex Ag_31·2 was exclusively formed from two different tris(thiazolyl) and hexa(thiazolyl) disk-shaped ligands, 1 and 2, with the aid of three Ag~+ ions. The variable-temperature ~1H NMR study on its complexation behavior revealed that metal-ligand exchanges between the two neighboring thiazolyl nitrogen donors of 2 take place at the three Ag~+ centers in concert. △H~(++) and △S~(++) for the exchange process were calculated to be 50.5 kJ mol~(-1) and -26.7 J mol~(-1) K~(-1), respectively, and its energy barrier at 298 K was estimated to be 58.5 kJ mol~(-1). Each concerted metal-ligand exchange leads to an intramolecular 60-rotational motion ((P)<->(M) conversion) between the two disk-shaped ligands.