One-pot synthesis of highly substituted dihydro-2-oxopyrols using nano-SnCl4/γ-Al2O3 as a mild solid lewis acid catalyst

Abstract

In this paper, highly substituted dihydro-2-oxopyrol derivatives were synthesized through a three component reaction of dialkylacetylenedicarboxylate, formaldehyde and aniline derivatives in the presence of nano-SnCl4/γ-Al2O3. The reaction was proceeded in ethanol as the solvent under reflux conditions. Nano-SnCl4/γ-Al2O3 was prepared via the reaction of SnCl4 with nano-γ-Al2O3 and characterized by FT-IR, XRD, FE-SEM, TEM, EDS,EDS-mapping, BET and TGA. Reusability of nano-SnCl4/γ-Al2O3 was examined in five runs, successfully. Short time of the reactions, good to excellent yield of products, heterogeneous conditions and reusability of the nano-catalyst are some of advantages of this green and environmental methodology.

Keywords

• Highly substituted
• Dihydro-2-oxopyrols
• Nano-SnCl4/γ-Al2O3
• Heterogeneous
• One pot synthesis
• Acid catalyst