Ruthenium Nanoparticles Immobilized on Nano-silica Functionalized with Thiol-Based Dendrimer: A Nanocomposite Material for Oxidation of Alcohols and Epoxidation of Alkenes

Abstract

Abstract: In this work, ruthenium nanoparticles were immobilized on thiol-based dendrimer functionalized nano-silica and its catalytic activity was investigated in the oxidation reactions. To do this, silica nanoparticles were functionalized with a thiol-based dendrimer, and this dendritic material was used as a host for immobilization of ruthenium nanoparticles as guest species. Different analytical tools such as FT–IR and UV–vis spectroscopies, CHNS, ICP and TGA analyses, and TEM and SEM microscopic techniques were used to characterize the prepared catalyst. The catalytic activity of this nanocomposite material as a heterogeneous catalyst was studied in the epoxidation of alkenes and oxidation of alcohols with tert-butyl hydroperoxide (tert-BuOOH) and the corresponding products were obtained in good to excellent yields. Moreover, this catalyst can be well-dispersed in the reaction medium, conveniently separated from the reaction mixture, and reused several times without significant loss of its activity. Graphical Abstract: Runp–nSTDP provided a highly stable, active, reusable, and solid-phase catalyst for preparation of a series of epoxides and aldehydes. © 2018, Springer Science+Business Media, LLC, part of Springer Nature.