Reactions of Difluorosilylene with Amines,Phosphines and Halomethanes The First Evidence of the Insertion of Difluorosilylene into Tetrafluorosilane

The reactions of SiF₂/SiF₄ with amines, phosphines and various halomethanes were studied. The results show that in the presence of strong Lewis base (Et₃N, HNEt₂, PR₃, PR₂Cl), SiF₂ inserts initially into SiF₄ to form Si₂F₆, which was followed by subsequent reactions leading to products containing SiF₃ groups. This is the first report of the insertion of SiF₂ into SiF₄. When the reactants were a weaker base (such as RPCl₂, CX₃Br, X=F, Cl), insertion of SiF₂ into P-Cl and C-Br bonds became predominant.