Silver(I) Complexes of 2,2′;6′,4″-Terpyridine: The Formation of Discrete Dimers versus Helical Polymers is Anion Dependent

The ligand 2,2′;6′,4″-terpyridine combines a chelating bipyridine group and terminal pyridine donor into a single molecule which is incapable of bonding all three donor N-atoms to a single metal center. Upon chelation to Ag(I), a pro-chiral, building block is produced which can subsequently aggregate by terminal coordination of the pyridine nitrogen. Two forms are possible; a discrete bimetallic complex with a center of symmetry and an infinite helical coordination polymer. Which of these structures occurs is dependent upon the counter anion.