Metalloid Ge9R3- Clusters with Various Silyl Substituents: From Shielded to Open Cluster Cores

The synthesis and characterization of the metalloid germanium clusters {Ge-9[Si(SiMe3)(2)(SiPh3)](2)}(2-) (1), {Ge-9[Si(SiMe3)(3)][Si(SiMe3)(2)(SiPh3)] (2)}(-) (2), {Ge-9[Si(SiMe3)(2)(Si/Pr-3)](3)}(-) (3), and [Ge-9(SiHtBu(2))(3)](-) (4), which were obtained by the reaction of the Zintl anion Ge-9(4-) with different silyl halides, are presented. Compound 4 is the sterically least protected soluble Ge9R3- cluster known to date, and thus has interesting structural features and may open the way to new coordination modes of metalloid Ge9R3- clusters.