Synthetic access to a hydrocarbon-soluble trifluorinated Ge(II) compound and its Sn(II) congener.

Trifluorinated germanium anions attracted attention of theoretical chemists already in the late 1990s to predict their physical and chemical properties. However these species were not synthesized in the laboratory, although substantial evidence for their existence was obtained from the mass spectrometry of GeF4. The present study shows that controlled fluorination of LMNMe2 (L = PhC(N(t)Bu)2, M = Ge, Sn) using HF·pyridine in toluene leads to the formation of [LH2](+)[MF3](-) under elimination of HNMe2. The products contain the trifluorinated Ge(II) and Sn(II) anionic species which are stabilized by interionic H···F bonds. The new compounds were characterized by single crystal X-ray structural analysis, NMR spectroscopy, and elemental analysis.