Zirconia-Modified Superacid UDCaT-5: An Efficient and Versatile Catalyst for Alkylation Reactions under Solvent-Free Conditions

Abstract

UDCaT-5, a modified version of zirconia, efficiently catalyzes alkylation of phenols with alcohols under environmentally safe, heterogeneous reaction conditions with high selectivity and in excellent yields. The high content present in UDCaT-5 with preservation of tetragonal phase of zirconia was responsible for the superactivity. Several phenolic compounds carrying either electron-sulfer releasing or electron-withdrawing substituents in the ortho, meta, and para positions afforded high yields of the products.

ACKNOWLEDGMENTS

G. D. Y. acknowledges the financial support from the Darbari Seth Professorship Endowment. G. S. P. is thankful to Council of Scientific and Industrial Research (CSIR), New Delhi, for awarding a junior research fellowship during this work. G. D. Y. acknowledges the hospitality of Purdue University, West Lafayette, for the invitation as a Distinguished Visiting Scholar under its Asian Initiative, which allowed him to spend time on creative pursuits.

Notes

^a Temperature: 140 °C.

^b Temperature: 180 °C.