1,2- and 1,1-Migratory Insertion Reactions of Silylated Germylene Adducts

The reactions of the PMe(3) adduct of the silylated germylene [(Me(3)Si)(3)Si](2)Ge: with GeCl(2)·dioxane were found to yield 1,1-migratory insertion products of GeCl(2) into one or two Ge–Si bonds. In a related reaction, a germylene was inserted with tris(trimethylsilyl)silyl and vinyl substituents into a Ge–Cl bond of GeCl(2). This was followed by intramolecular trimethylsilyl chloride elimination to another cyclic germylene PMe(3) adduct. The reaction of the GeCl(2) mono-insertion product (Me(3)Si)(3)SiGe:GeCl(2)Si(SiMe(3))(3) with Me(3)SiC≡CH gave a mixture of alkyne mono- and diinsertion products. While the reaction of a divinylgermylene with GeCl(2)·dioxane only results in the exchange of the dioxane of GeCl(2) against the divinylgermylene as base, the reaction of [(Me(3)Si)(3)Si](2)Ge: with one GeCl(2)·dioxane and three phenylacetylenes gives a trivinylated germane with a chlorogermylene attached to one of the vinyl units.