Total synthesis of rubrolide M and some of its unnatural congeners

Two protocols have been developed for the Pd-catalyzed regioselective synthesis of 4-aryl-3-chloro-2(5H)-furanones starting from 3,4-dichloro-2(5H)-furanone. These monochloro derivatives have then been used as precursors to (Z)-4-aryl-5-[1-(aryl)methylidene]-3-chloro-2(5H)-furanones including naturally-occurring rubrolide M.