2,4,6-trichloro-1,3,5-triazine-promoted synthesis of 1,8-dioxo-octahydroxanthenes under solvent-free conditions

A practical protocol has been developed for the synthesis of 1,8-dioxo-octahydroxanthenes from aromatic aldehydes and 5,5-dimethylcyclohexane-1,3-dione under solvent-free conditions in the presence of wet 2,4,6-trichloro-1,3,5-triazine ( TCT, cyanuric chloride). The desired products were obtained in high yields with a simple and environmentally benign procedure.