Synthesis of Tetrahydrobenzo[a]xanthene-11-one Derivatives Using ZrO2–SO3H as Highly Efficient Recyclable Nano-catalyst


Young Researchers and Elite Club, Mashhad Branch, Islamic Azad University, Mashhad, Iran


The catalytic effect of Zirconia Sulfuric Acid (ZrSA) nanoparticle which is synthesized from the
reaction of ZrO with chlorosulfonic acid has been investigated in the synthesis of
tetrahydrobenzo[a]xanthene-11-ones by one-pot three-component reaction of β-naphthol,
aromatic aldehydes, and dimedone. Different reaction conditions were studied in the presence of
ZrSA nanoparticle as catalyst. The results showed that ZrSA exhibited high catalytic activity
towards the synthesis of tetrahydrobenzo[a]xanthene-11-ones, with the desired products being
formed in high yields. Furthermore, the catalyst was recyclable and could be reused at least three
times without any discernible loss in its catalytic activity. Overall, this new catalytic method for
the synthesis of tetrahydrobenzo[a]xanthene-11-ones provides rapid access to the desired
compounds under solvent-free conditions at 110 °C following a simple work‐up procedure, and
avoids the use of harmful organic solvents. This method therefore represents a significant
improvement over the methods currently available for the synthesis of