Oxidation of [Ge9{Si(SiMe3)3}3]−with LnI3(Ln = Eu, Sm, Yb): Isomerism of Metalloid Germanium Clusters

The oxidation of K[Ge9(Hyp)3] (Hyp = Si(SiMe3)3) with lanthanide triiodides LnI3(Ln = Eu, Sm, Yb) leads to the formation of novel clusters with a Ge18-core isolated as a co-crystallizate of Ge*18(Hyp)6(1a) and Ge18(Hyp)5(Si(SiMe3)2)(SiMe3) (1b). Clusters 1aand 1bdiffer distinctly from the known cluster Ge18(Hyp)6(A), which has been found earlier in the reaction of K[Ge9(Hyp)3] with FeCl2and now identified as an intermediate product in the production of compounds 1aand 1b. These three compounds A, 1a, and 1bare thus structural isomers being the first example of genuine isomerism in metalloid main-group cluster compounds.