A Facile Synthesis of Xanthene‐1,8(2H)‐dione Derivatives by Using Tetrapropylammonium Bromide as Catalyst

Several new derivatives of 9‐aroyl‐3,4,5,6,7,9‐hexahydro‐1H‐xanthene‐1,8(2H)‐dione have been synthesized in yields varying from high to excellent by the condensation reaction of arylglyoxals with 1,3‐diketones (cyclohexane‐1,3‐dione or dimedone) and TPAB as an inexpensive, recoverable, and non‐toxic catalyst in the presence of ethanol/water under reflux conditions.