Preparation and X-ray crystal structure of the complex µ-chloro-bis[bis(imidazole)copper(I)] chloride

Abstract

The title complex, [Cu₂Cl(Him)₄]Cl, has been prepared from copper(I) chloride and imidazole (Him) in acetonitrile solution. It crystallises in the trigonal space group P3₂21, with a= 8.546(1), c= 21.370(3)Å, and Z= 3. The trigonally co-ordinated Cu atoms are joined by a Cl bridge [Cu–Cl 2.564(2)Å, mean Cu–N 1.904(5)Å, Cu–Cl–Cu 95.5(1)°, Cu ⋯ Cu 3.797(3)Å]. The Cl^– anion lies between the two hinged Cu co-ordination planes, with Cu ⋯ Cl 3.134(2)Å. [Cu₂Cl(Him)₄]Cl reacts readily and irreversibly with dioxygen in solution; in the solid state, only surface reaction occurs, although the molecular structure is similar to the active centre proposed for hemocyanin proteins.