Triisopropoxysilyl-functionalized oxide nanoparticles using a di-tert-butyl phosphonate ester as the surface grafting agent

The synthesis of a bifunctional coupling reagent possessing a triisopropoxysilyl group and a tert-butyl phosphonate ester is described. The tert-butyl phosphonate ester was used as an efficient and selective grafting reagent for the anchoring of the triisopropoxysilyl group at the surface of TiO2 and SnO2 nanoparticles under mild conditions. The triisopropoxysilyl group remained intact and did not react at the surface of the oxide nanoparticles. The reactivity of the triisopropoxysilyl group was then further investigated.