A comparative study of TiO2, Al2O3, and Fe3O4 nanoparticles as reusable heterogeneous catalysts in the synthesis of tetrahydrobenzo[a]xanthene-11-ones

Abstract

Catalytic effect of three nanosized metal oxides TiO₂, Al₂O₃ and Fe₃O₄ nanoparticles in the onepot synthesis of tetrahydrobenzo[a]xanthene-11-ones by three-component reaction of β-naphthol with aromatic aldehydes and dimedone has been studied. Various reaction conditions were tested in the presence of TiO₂, Al₂O₃ and Fe₃O₄ nanoparticles. The results demonstrated that nano Fe₃O₄ was the more efficient heterogeneous catalyst than Al₂O₃ and Fe₃O₄. The reaction completed within shorter period of time under solvent-free conditions with higher yield. The catalysts used were recyclable.