4-Hydroxy Pyridinium Triflate@SiO2 Nanoparticles as a Novel Efficient Catalyst for Fries Rearrangement of Aryl Esters with High Selectivity.

INTRODUCTION: We developed a simple, fast and new method for the Fries rearrangement of aryl esters. MATERIALS AND METHODS: 4-Hydroxy pyridinium triflate functionalized silica is a very efficient, reusable and economically available catalyst for the Fries rearrangement in solvent-free condition and under microwave irradiation. RESULTS AND DISCUSSION: Also, a notable selectivity was observed in the presence of 4-hydroxy pyridinium triflate functionalized silica. CONCLUSION: Selectivity, shorter reaction time, high yield, and easy work-up are advantages of this synthetic method.