Synthese, schwingungsspektren und normalkoordinatenanalyse von 1,2-Di-tert-butyltetrahalogendisilanen

Abstract The cleavage of the silicon-phenyl bonds of 1,2-di-tert-butyltetraphenyldisilane with hydrogen halides HCl, HBr and HI produces 1,2-di-tert-butyltetrachlorodisilane, 1,2-di-tert-butyltetrabromodisilane and 1,2-di-tert-butyltetraiododisilane in good yields. t BuBr 2 SiSiBr 2 t Bu easily reacts with ZnF 2 in diethylether to form the tetrafluoroderivative. With trifluormethanesulfonicacid, two phenyl groups can be removed selectively from t BuPh 2 SiSiPh 2 t Bu. The subsequent reaction with LiX gives the disilanes t BuPhXSiSiXPh t Bu (X = F, Cl, Br, I). Finally, the asymmetric tert-butyldisilanes t Bu 2 HSiSiPh 2 Bu, t Bu 2 t BrSiSiBr 2 t Bu and t BuHSiSiH 2 t Bu can be obtained from Ph 2 t BuSiK and t Bu 2 SiHCl, followed by bromination with HBr and reduction with LiAlH 4 . The infrared and Raman vibrational spectra of t BuX 2 SiSiX 2 t Bu are reported and assigned with the aid of a normal coordinate analysis.