Silica chloride catalyzed synthesis of 14-aryl-14H-dibenzo[a,i]xanthene-8,13-diones

A simple and facile synthesis of 14-aryl-14H-dibenzo[a,i]xanthene-8,13-dione derivatives was accomplished by the one-pot condensation of β-naphthol, aldehydes, and 2-hydroxy-1,4-naphthoquinone under solvent-free conditions in the presence of the heterogeneous catalyst, silica chloride. This method has the advantages of high yield, clean reaction, simple methodology and short reaction time. The catalyst could be recycled and reused three times without significant loss of activity. The structures of the novel compounds were confirmed by IR, 1H NMR, 13C NMR, and elemental analysis.