An efficient and simple procedure for the synthesis of 1,8-dioxo-octahydroxanthenes from the aromatic aldehydes and 5,5dimethylcyclohexane-1,3-dione (dimedone) in the presence of Fe3O4@SiO2@COOH Polymerized as an inexpensive and reusable catalyst is described. The salient features of this methodology are: high yields, short reaction times, solvent-free conditions
