Chair-form [Ag2(1,2-bimb)2]2+ in silver(I) complexes containing the ditopic ligand 1,2-bis(1-imidazolylmethyl)benzene (1,2-bimb)

The ditopic ligand 1,2-bis(1-imidazolylmethyl)benzene (1,2-bimb) and its silver(I) complexes [Ag-2(1,2-bimb)(2)](PF6)(2) (1) and {[Ag-2(1,2-bimb)(2)](2)(SbF6)(4)}(n) (2) were prepared and their structures characterized by X-ray crystallography. Both complexes contain the chair-form unit [Ag-2(1,2-bimb)(2)](2+) with Ag(I) linearly coordinated by N-Im (Im = 1-imidazolyl) from the Im groups of two 1,2-bimb. However, the [Ag-2(1,2-bimb)(2)](2+) units are positioned differently in forming 1D infinite chains through weak argentophilic interactions: linear chains in 1 with the units oriented in same direction are formed via Ag(. . .)pi interactions, while polymeric chains constructed via (AgAg)-Ag-. . . interactions in 2 are observed with the units arranged in alternate directions. Differences in supramolecular structures may be a result of different size of the anions. (C) 2003 Published by Elsevier B.V.