ChemInform Abstract: General and Expedient Synthesis of 1,4‐Dioxygenated Xanthones.

Abstract

General and Expedient Synthesis of 1,4-Dioxygenated Xanthones. -The desired title compounds are available starting from the corresponding salicylaldehyde substrates. The naturally occurring xanthone (IX) is synthesized in 7 steps and an overall yield of 22%, a significant improvement compared to former procedures. The designed structure (X) for dulcisxanthone C is revised to be consistent with (IX). In the case of precursors (XII), spirocycles (XIII) and xanthones (XIV) are formed as inseparable mixtures. The spirocycles can be easily rearranged to the xanthones under mild conditions. -(NICHOLS, A. L.; ZHANG, P.; MARTIN*, S. F.; Org. Lett. 13 (2011) 17, 4696-4699, http://dx.