Mo (VI)/ZrO2 coated on honeycomb monolith as solid acid green catalyst for the acetylation of substituted alcohols and amines under solvent free conditions

Abstract

Honeycomb (HC) monolith coated with solid acids such as Mo (VI)/ZrO₂ (MZ) with different Mo loadings (2, 6 and 10%) have been prepared by wet impregnation method and characterized by NH₃ –TPD, BET surface area, PXRD, ICP-OES, SEM, TEM and EDAX techniques. These catalysts have been used as for the synthesis of O and N-acetylation reactions by the condensation of various alcohols with acetic anhydride under solvent free conditions in shorter times (20 min) at moderate temperature (70°C). Especially, 6% Mo (VI)/ZrO₂ catalysts are found to be highly acidic and also resulted in high yields of O and N acetylated products up to ~99%. This methodology offers several advantages such as excellent yields, easy procedure, mild and environmentally benign conditions. MZ catalysts are found to be economical, efficient and highly active, recyclable and reusable up to 6 reaction cycles without much loss of their activity.