Correction of a Reported Xanthone Synthesis: The Preparation of a Benzo[c]coumarin

Reinvestigation of a reported synthesis of 5,8‐dihydroxy‐1,3‐dimethoxyxanthone from the reaction of 3,5‐dimethoxyphenol with 2‐(methoxycarbonyl)‐1,4‐benzoquinone resulted in the identification of the product as the isomer of benzo[c]coumarin, i.e., 7,10‐dihydroxy‐1,3‐dimethoxy‐6H‐dibenzo[b,d]pyran‐6‐one, established by X‐ray crystallography. This requires the revision of the structures of the derivatives that were reported.