1-(1-Propylsulfonic)-3-methylimidazolium chloride Brønsted acidic ionic liquid catalyzed one-pot synthesis of 14-aryl-14H-dibenzo[a,j]xanthene derivatives under solvent-free conditions

A rapid, green and efficient method for the synthesis of 14aryl14Hdibenzo[a,j]xanthene derivatives through a onepot condensation of 2naphthol with various aromatic aldehydes in the presences of several acidic ionic liquids including [PSMIM]Cl, [BMIM]HSO4, [BMIM]Cl, [BMIM]Br, and [BMIM]BF4 as organocatalysts and taskspecific acidic ionic liquids (AILs) under solventfree conditions is described. Compared with other synthetic methods, this new method has the advantages such as milder reaction conditions, good to excellent yields, short reaction times, and environmentally benign procedure. Also, 1(1Propylsulfonic)3methylimidazolium chloride [PSMIM]Cl acts as a catalyst under solventfree conditions and can be recovered and reused six times without apparent loss of its catalytic activity.