ZrOCl2·8H2O as an efficient and recyclable catalyst for the clean synthesis of xanthenedione derivatives under solvent-free conditions

ZrOCl2·8H2O was found to be an efficient and recyclable catalyst for the reaction of aromatic aldehydes with dimedone to afford 1,8-dioxo-1,2,3,4,5,6,7,8-octahydroxanthenes under solvent-free conditions. Short reaction time, excellent yields and simple work-up are the advantages of this procedure. The interaction obtained from XRD studies was shown that the catalyst loses H2O during the reaction but it did not affect catalytic activity of the catalyst and the catalyst could be reused several times.