Modification of the base-catalysed disproportionation of methylchlorodisilanes

The product range of the base-catalysed disproportionation of methylchlorod isilanes, especially 1,1,2,2-tetrachlorodimethyldisilane, can be modified b y adding phenyltrichlorosilane to obtain phenyl containing polysilanes. The first formed phenyl substituted oligomers up to a tetrasilane and some fur ther derivatives could be prepared on different synthetic routes, too. Sily lstannane formation as well as a reduction to elemental tin result from the co-disproportionation of 1,1,2,2-tetrachlorodimethyldisilane and methylchl orostannanes whereas SnCl4 reacts quantitatively to SnCl2 and GeCl4 gives a germanium subchloride. The disproportionation can be applied to 1,1,2,2-te trafluorodimethyldisilane instead of the chloro compound and yields a branc hed methylfluoropolysilane as an oily residue besides MeSiF3.