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An efficient and convenient methodology is introduced for preparation of xanthones and dixanthones through direct coupling of salicylic acids and phenols. It is based on the use of POCl 3 and catalytic amount of calix(4)arene sulfonic acid as a highly thermally stable and recyclable organocatalyst. A variety of salicylic acids and phenols were treated with POCl 3 and the catalyst in the absence of solvent at 80 o C which afforded the corresponding xanthones in good to high yields.

One-Pot Synthesis of Xanthones and Dixanthones Using Calix[4]arene Sulfonic Acid Under Solvent Free Condition