The main purpose of this work was proposing a versatile and capable method for the synthesis of diverse xan- thenediones from the three-component condensation reaction of two moles of dimedone and one mole of various aldehydes by zirconium tetrachloride (I) or ammonium metavanadate (II) catalysts in solvent-free conditions at 60 ◦C for I and 80 ◦ C for II catalysts. The products were characterized by comparison of their melting points, IR and NMR spectra with authentic samples. Also, the proposed reaction mechanism for the synthesis of xanthe- nediones was confirmed at M062x/def2-SVP level of theory in the gas phase
