Silicon–nitrogen compounds. Part IX. Self-dehydrofluorination of tetrafluorosilane–amine adducts as a route to substituted aminofluorosilanes

Abstract

Adducts of tetrafluorosilane and secondary amines readily undergo self-dehydrofluorination on moderate heating to yield as volatile products substituted aminofluorosilanes, SiF₃NR₂(R = Me, Et, Prⁿ, Buⁿ; R₂= C₄H₈, C₅H₁₀). Similar adducts of primary amines less readily give disilazanes, (SiF₃)₂NR (R = Prⁿ, Buⁿ, Bu^s) or the silylamine SiF₃NHBu^t. Yields are increased if an excess of SiF₄ is present. Entirely gaseous SiF₄–amine mixtures do not react under these conditions: a liquid phase must be present for high yields. I.r., mass, and n.m.r. spectra of the new compounds are discussed. Tetrafluorogermane and diethylamine do not react in a gas–liquid system at 130 °C.