Preparation of 3,4,5,3′-Tetramethoxy-4′,5′-Methylenedioxybenzophenone and Bis-(3-Methoxy-4,5-Methylenedioxy)-Benzophenone

The preparation of 3,4,5,3′-tetramethoxy-4′,5′-methylenedioxybenzophenone (I) and bis-(3-methoxy-4,5-methylenedioxy)-benzophenone(II) were reported. The synthesis of these compounds were accomplished using two separate synthetic routes starting from gallic add and its derivatives to the corresponding benzils. Both compound I and II were obtained by benzilic acid rearrangement of the benzils and followed by an oxidative decarboxylation.