Transesterification of 3-aminopropyltriethoxysilane with triphenylsilanol

It has been shown that triphenylsilanol is capable of replacing one or two ethoxy groups in 3-aminopropyltriethoxysilane. 3-Aminopropyl(triphenylsiloxy)(diethoxy)silane (Ph3SiO)(EtO)2Si-CH2CH2CH2-NH2 and 3-aminopropylbis(triphenylsiloxy)(ethoxy)silane (Ph3SiO) 2(EtO)Si-CH2CH2CH2-NH2 have been obtained, yielding 56% and 27%. 3-Aminopropyl(triphenylsiloxy)(diethoxy)silane is not subject to hydrolysis by water in dioxane. Addition of the Bu4NF catalyst results in formation of 3-aminopropyl(triphenylsiloxy)(dihydroxy)silane (Ph3SiO)(HO)2SiCH2CH2CH2NH2 and its condensation product to polymeric HO[(Ph3SiO)Si(CH2CH2CH2NH2)O]nH. The compounds are characterized by elemental analysis, IR and NMR spectroscopy.