A simple and efficient procedure for synthesis of 1,8-dioxo-octahydroxanthenes by one-pot condensation of aromatic aldehydes with 5,5-dimethyl-1,3-cyclohexanedione under solvent-free conditions using ionic liquid [Et3NH][HSO4] as catalyst is described. The procedure offers several advantages including cleaner reaction profiles, use of easily available, cheap, recyclable and environmentally benign nature of catalyst, high yields, and simple experimental and work-up procedures. (C) 2012 Elsevier B.V. All rights reserved.