Investigating effect of cerium (IV) sulfate tetrahydrate as reusable and heterogeneous catalyst for the one‐pot multicomponent synthesis of polyhydroquinolines

Abstract

Cerium (IV) sulfate tetrahydrate, Ce(SO4)2.4H2O used as a new inorganic solid acidic catalyst for the synthesis of polyhydroquinoline derivatives via four-component Hantzsch reaction of aromatic/aliphatic aldehydes, 5,5-dimethylcyclohexane-1,3-dione (dimedone), ethyl acetoacetate and ammonium acetate under solvent-free conditions at 120 °C. This method has the advantages of high yields (88-97 %), clean reaction, simple methodology, and short reaction time (15-25 min). However, the aromatic aldehydes whether electron donating or electron withdrawing showed simple transformation with the excellent yields than the other aliphatic. Furthermore, the catalyst is inexpensive and readily available and can be recovered conveniently and reused efficiently without considerable decrease in its catalytic activity.