Background: Solid acids and superacids based on supported heteropoly acids have become
very popular. Use of mesoporous materials such as mesocellular silica foam (MCF) was made in this
work for its superior textural properties and stability.
Methods: MCF was used as a support for cesium substituted dodecatungstophosphoric acid (DTP). 20%
(w/w) Cs2.5H0.5PW12O40 (Cs-DTP)/MCF was used as a superacidic heterogeneous catalyst for acetylation
of p-anisyl alcohol. p-Anisyl acetate is widely used as fragrance and perfumery agent in a number
of formulations. The catalyst was fully characterized by various techniques before and after use.
Results: The catalysts selected for comparison were MCF, bulk Cs-DTP, commercial catalyst Amberlyst-
15, and 20% (w/w) Cs-DTP/MCF. Among all 20% (w/w) Cs-DTP/MCF was found to be the best
catalyst with 57.6% conversion of p-anisyl alcohol with 100% selectivity in 90 min at 313 K. Reaction
parameters were optimized through a systematic study. Langmuir-Hinshelwood-Hougen-Watson
(LHHW) model with weak adsorption of all species was fitted leading to overall second order kinetics.
Apparent activation energy is 13.4 kcal/mol.
Conclusion: 20% (w/w) Cs2.5H0.5PW12O40 (Cs-DTP)/MCF was found to be the most active, selective
and reusable catalyst under mild condition for the acetylation of p-anisyl alcohol to p-acetyl acetate.