A series of 9-aryl-hexahydroacridine-1,8-diones are synthetized with good to excellent yields (50-99%) via a one-pot four-component reaction of dimedone, aromatic aldehydes and ammonium acetate in the presence of 4 angstrom molecular sieves modified with iron(III) as an efficient heterogeneous catalyst, in ethanol. The process offers the advantages of high yields, mild reaction conditions and easy work-up procedure. The catalyst can be reused without significant loss of activity. [GRAPHICS] .