Darstellung und spektroskopische charakterisierung verzweigter funktioneller hexasilangerüste

When 2-chloro-1,1,1,3,3,3-hexaphenyltrisilane is treated with an excess of HCl in a stainless steel autoclave, two phenyl groups per silicon atom are substituted by Cl yielding 1,1,2,3,3-pentachloro-1,3-diphenyltrisilane. All phenyl groups are replaced upon treatment with HCl/AlCl₃ in benzene solution. Coupling of the resulting trisilanes with (^tBu)₂Hg leads to branched hexasilanes (XCl₂Si)₂SiClSiCl(SiCl₂X)₂ (X = Ph, H), which are converted to the corresponding silicon hydrides by LiAlH₄. From the reaction of 1,4-diphenyl-2,3-bis(phenylsilyl)tetrasilane with HCl or HBr the tetrahalohexasilanes (ClH₂Si)₂SiHSiH(SiH₂Cl)₂ and (BrH₂Si)₂SiHSiH(SiH₂Br)₂ can be obtained.