Mechanochemical assisted acetylation of aromatic amines, phenols and thiol catalysed by RHA-SiO2 (NPs)@BO3H3

Abstract

In this work, rice husk-derived silica nanoparticles (RHA-SiO₂-NPs) are synthesized and further surface functionalized with boric acid to avoid tedious recycling of the silica NPs and also increasing Lewis acid strength of the silica. The prepared heterogeneous catalysts (RHA-SiO₂NPs@BO₃H₃) demonstrated application in the formation of acetyl derivatives of aryl amine, thiol and phenol in the presence of acetic anhydride under grindstone method gave excellent product isolation (98% yield in 5-8 min). The benefit of this method found simple, efficient, solvent-free and reusable. The catalyst prepared in this work derived from the agro-waste and functionalized for the efficient catalytic activity.