Multiple Silyl Exchange Reactions: A Way to Spirooligosilanes

Tetrakis(dimethylphenylsilyl)silane can be obtained in a one-pot reaction by treating tris(trimethylsilyl)silylpotassium with excess dimethylphenylfluorosilane. This silyl exchange process works also with pentamethylfluorodisilane to give tetrakis(pentamethyldisilanyl)silane. The use of 1,4-difluorooctamethyltetrasilane produces cyclic compounds such as 1,1-bis(trimethylsilyl)octamethylcyclopentasilane or even spirocyclic ones such as hexadecamethylspiro[4.4]nonasilane.