N. Montazeri - Department of Chemistry, Tonekabon Branch, Islamic Azad University, Tonekabon, Iran.

Pyrano [۲,۳-d] pyrimidinone derivatives have received considerable interest from the pharmaceutical industry due to their wide range of interesting biological and therapeutic properties. Nano Al۲O۳ was found to be a highly efficient solid acid catalyst for the preparation of pyrano [۲,۳-d] pyrimidinone derivatives from the reaction of barbituric acid, aryl aldehyde and malononitrile. Al۲O۳ nanoparticles with the average diameter of ۱۵ nm were used four different contents of ۱۰, ۱۵, ۲۰ and ۲۵ mol%. Present methodology offers several advantages, such as high yields, short reaction time, simple procedure with an easy work-up and mild reaction conditions. The products were obtained in high yields under reflux in H۲O:EtOH (۱:۱). We believe this applicability of nano Al۲O۳ with mentioned advantages makes our method superior over all previous reported methods to the synthesis of pyrano [۲,۳-d] pyrimidinone derivatives. The structures of the products were characterized by their physical constants and comparison of their melting points with those of authentic samples.

Nano Al۲O۳, Barbituric acid, Aryl Aldehyde, Malononitrile, catalyst