Lineare Tetrasilane mit mittelstaendigen Substituenten-Oligosilane mit optischer Aktivitaet

Article abstract of DOI:10.1016/0022-328X(93)80450-P

The chiral tetrasilane 2,3-diphenyltetrasilane (2) is formed by the stepwise cleavage of Si-aryl bonds in appropriate aryltetrasilanes with HCl under pressure and subsequent reduction with LiAlH4.HPh2SiSiPh2SiPh2SiPh2H affords a mixture of conformers, whereas Mes2HSiSiPh2SiPh2SiHMes2, which is accessible from Mes2HSiLi and Ph2SiCl2, only yields 2 because mesityl groups proved to be much more reactive towards HCl than towards phenyl groups.Further reaction of 2 with HCl or HBr affords 2,3-dichlorotetrasilane (7) and 2,3-dibromotetrasilane (8).The diastereomers thatappear because of the presence of 2 asymmetric Si atoms in 2, 7 and 8, can be easily distinguished in NMR and GC/MS experiments.