Crystal structure of catena-poly[[[di-aqua-[1,2-bis(pyridin-4-yl)ethene]{4-[2-(pyridin-4-yl)ethen-yl]pyridinium}gold(I)iron(II)]-di-μ-cyanido] bis-[dicyanido-gold(I)] 1,2-bis-(pyridin-4-yl)ethene dihydrate]

Abstract

In the title compound [Fe(bpe)(Hbpe)Au(CN)₂][Au(CN)₂]₂·bpe·2H₂O} _n [where bpe = 1,2-bis-(pyridin-4-yl)ethene, C₁₂H₁₀N₂], the Fe^II ion is coordinated in a distorted octa-hedral [FeN₄O₂] environment by two di-cyano-aurate anions, two water mol-ecules and two partially protonated 1,2-di(4-pyrid-yl)ethyl-ene mol-ecules. Di-cyano-aurate anions bridge the Fe^II cations, forming infinite chains, which propagate along the a-axis direction. The chains are connected via aurophilic inter-actions with two non-coordinated di-cyano-aurate anions for each Fe^II ion. The polymeric chains inter-act with each other via π-π stacking between the guest bpe mol-ecules and multiple hydrogen bonds.

Keywords: aurophilic inter­actions; crystal structure; di­cyano­aurate; iron(II) complex; polymeric complex.