Sulfated zirconia as an efficient heterogeneous and reusable catalyst for one pot synthesis of flavanones

A simple and one pot process for the synthesis of flavanones in the presence of SO42-/ZrO2, a reusable, heterogeneous catalyst has been described. The reactions were conducted both with and without solvent (using toluene as solvent) at 140 °C with reaction times of 3–4 h. Under these conditions several examples were found with very good yields (73–87%) and up to 83% selectivity. The catalyst was easily recycled and reused without loss of its catalytic activity. The present synthetic method is a simple, clean and environment friendly alternative for synthesizing substituted flavanones.