A Green and Efficient Synthesis of 9-Aryl-3,4,5,6,7,9-hexahydroxanthene-1,8-dione using a Task-Specific Ionic Liquid as Dual Catalyst and Solvent

A green and efficient method for the preparation of 9-aryl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione has been developed using functionalized ionic liquids as a catalyst and a reaction medium. The nature of both the counter anion and cation influence the catalytic performance of the ionic liquids. The ionic liquid can be recycled and reused without apparently loss of activity.