Boron Cluster Anion [B12H12]2- in Zinc(II) and Cadmium(II) Cornplexation at the Presence of N-Donor Heterocyclic Ligands

Zinc(II) and cadmium(II) complexation with the dodecahydrido-closo-dodecaborate anion [B12H12](2-) in the presence of benzimidazole ligands 1-methylbenzimidazo-2-yl-methyleneaniline (L-1) and 1-ethyl-2-(4-methoxyphenyl)azobenzimidazole (L-2) was studied. A number of Zn(II) and Cd(II) complexes with the [B12H12](2-) anion and ligands L-1 or L-2 were obtained and characterized. Effect of the metal nature on the composition and structure of the resulting compounds was determined. Only tris-chelate zinc(II) complexes with the [B12H12](2-) anion were isolated. For cadmium, first examples of mixed-ligand complexes with the [B12H12](2-) anion coordinated by the metal atom via 3c2e (CdHB) bonds were isolated. Structures of complexes [Zn(L-1)(3)][B12H12]center dot 2CH(3)CN, [Cd(L-1)(2)[B12H12]]center dot 2CH(3)CN and [Cd(L-2)(2)(CH3CN)[B12H12]]center dot CH3CN were determined by X-ray diffraction. [GRAPHICS] .

Automated summary

In this study, the complexation of zinc(II) and cadmium(II) with the dodecahydrido-closo-dodecaborate anion [B12H12](2-) in the presence of benzimidazole ligands L-1 and L-2 was investigated. The resulting compounds were characterized and the influence of the metal nature on their composition and structure was determined. Tris-chelate zinc(II) complexes with the [B12H12](2-) anion were isolated, while mixed-ligand complexes with 3c2e (CdHB) bonds between the [B12H12](2-) anion and the cadmium atom were obtained for the first time.