Neue oder verbesserte Synthesen für Germa- und Germa-sila-alkane und ihre chlorierten Vorstufen / New or Improved Syntheses for Germa- and Germa-sila-alkanes and their Chlorinated Precursors

Abstract

Reaction of germanium powder and Cl₃SiCH₂Cl at 350 °C yields the l-germa-3-silapropane Cl₃SiCH₂GeCl₃, and (Cl₃SiCH₂)₂GeCl₂, in a “Direct Synthesis”. Cl₃GeCH₂CH₂GeCl₃ is obtained from HGeCl₃ and C₂H₂ as a “Hydrogermylation” product. Addition of CH₂=CHSiCl₃ to HGeCl₃ yields the 1-germa-4-silabutane Cl₃SiCH,CH₂GeCl₃, and Cl₃GeCH₂C(GeCl₃)=CH₂ is obtained similarly from ClCH₂C=CH and HGeCl₃-NEt₃. These Chlorogermanes or -germanes/silanes are converted into the corresponding germanes (silanes) by treatment with LiAlH₄ in tetralin as a solvent in the presence of triethyl(benzyl)ammonium chloride. The products are isolated in high yields and identified by standard analytical techniques, including ⁷³Ge NMR spectroscopy. Owing to their high volatility they are potential feed-stock gases for CVD experiments to generate a-GeC:H or a-Ge,Si,C:H materials.