Conformation driven complexation of two analogous benzimidazole based tripodal ligands with Ag(I) resulting in a trigonal prism and a coordination polymer

Two analogous tripodal ligands, namely, 1,3,5-tris(benzimidazol-1-ylmethyl)-2,4,6-triethylbenzene (1-Et) and 1,3,5-tris(benzimidazol-1-ylmethyl)-2,4,6-trimethoxybenzene (1-OMe) have been used for comple-xation with silver(I) tetrafluoroborate. A trinuclear Ag(I) salt, formulated as [Ag ₃ (1-Et) ₂ ] ^{3 +} (BF ₄ ) 3 - {\mathrm {\mathbf {-}}}-{\mathrm {\mathbf {3}}} •7CH ₃ CN •y H ₂ O was formed in the complexation reaction of 1-Et with silver(I) tetrafluoroborate, which consists of a trigonal prismatic cation formed by three bicoordinated Ag(I) coordinated with two 1-Et ligands. In case of the 1-OMe ligand, however, a one dimensional ladder, formulated as [(Ag(1-OMe)OH ₂ ) ⁺ (BF ₄ ) ^- •MeOH] ∞ {\mathrm {\mathbf {\infty } }} was obtained which is constituted of a tetracoordinated Ag(I) center in a distorted tetrahedral environment. The crystal structures of the ligand hydrates namely 1-Et •H ₂ O and 1-OMe •3.6H ₂ O have been discussed along with the structure of methanol solvate-hydrate of 1-Et. The imidazole rings of the Bim groups in 1-Et in the crystal structures of the ligand as well as in its coordination complex with the Ag(I) are pointed inward with respect to the central ring, whereas it is pointed outwards in the crystal structures of 1-OMe as well as its Ag(I) complex.