[Si(SiMe3)3]6Ge18M (M = Zn, Cd, Hg): neutral metalloid cluster compounds of germanium as highly soluble building blocks for supramolecular chemistry

Abstract

Very recently it was shown that the metalloid cluster compound {Ge₉[Si(SiMe₃)₃]₃}⁻1 can be used for subsequent reactions as the shielding of the cluster core is rather incomplete. So the reaction of 1 with M⁺ sources of group 11 metals gives metalloid cluster compounds of the formulae {MGe₁₈[Si(SiMe₃)₃]₆}⁻ (M = Au, Ag, Cu). These reactions can be seen as first steps into a supramolecular chemistry with metalloid cluster compounds. However, further build-up reactions lead to insoluble products, thus better soluble starting materials are needed for further build-up reactions. Here the first neutral MGe₁₈[Si(SiMe₃)₃]₆ (M = Hg, Cd, Zn) compounds are described, exhibiting a strongly enhanced solubility in inert solvents. Beside the synthesis, the structural properties as well as the bonding situations in these cluster compounds are discussed.