PUB - Publikationen an der Universität Bielefeld

Owing to the highly electron-withdrawing C2F5 groups, the tris(pentafluoroethyl)germane (C2F5)(3)GeH represents an interesting Bronsted acidic compound. The germane is accessible by the treatment of the corresponding halogenogermanes (C2F5)(3)GeX (X= Cl, Br) with Bu3SnH. After clarifying its molecular structure in the solid state by X-ray diffraction, the acidity of (C2F5)(3)GeH was examined by treatment with different bases, for example, 1,8-bis(dimethylamino) naphthalene. The resulting germanate(II) ion [Ge(C2F5)(3)](-) serves as a germyl group transfer reagent. The reaction with main-group and transition-metal complexes or organohalides opens access to a variety of different compounds, the structures of which were mostly determined by X-ray diffraction. The corresponding tricarbonylnickelate(0) complex [(CO)(3)NiGe(C2F5)(3)](-) also gives information about the pi-acceptor properties of the [Ge(C2F5)(3)](-) ligand. Furthermore, hydrogermylation reactions of (C2F5)(3)GeH with alkynes afforded different stereoisomers (alpha,beta-cis, beta-trans) depending on the respective reaction conditions and substrates.