Structural control of silver(I) coordination polymers: construction of two- and three-dimensional frameworks of silver(I) ions bridged by dicyanopyrazine derivatives

The silver(I) complexes of pyrazine-2,3-dicarbonitrile (2,3-dcpz), [Ag(2,3-dcpz)(ClO4)] (1a) and pyrazine-2,5-dicarbonitrile (2,5-dcpz), [Ag(2,5-dcpz)(X)] (2a: X=ClO4, 2b: X=CF3SO3) have been prepared and their molecular structure has been determined by X-ray crystallography. The silver ion in 1a prefers an octahedral coordination geometry and forms a two-dimensional square mesh structure. On the other hand, the silver ion in both 2a and 2b prefers a distorted square pyramidal coordination geometry that forms a three-dimensional structure with a cavity. By changing the bridging angle of the ligands and the size of the solvent, we could successfully control the crystal structure of the silver(I) coordination polymers.