The racemic 1,2-secomicrominutinin (25) was synthesized employing the intramolecular cycloaddition reaction of an (alkenyloxy)ketene, prepared from the corresponding tosylate. The (alkenyloxy)ketene undergoes intramolecular [2+2] cycloaddition to give tricyclic benzocyclobutafuranone (16), which by Baeyer-Villiger oxidation gives a benzofuranofuranone (17). Reaction of the latter compound with methyl propiolate, catalyzed by triphenylphosphine, produced the cinnamic ester derivative (25).
1,2-secomicrominutinin; benzofuranofuran; intramolecular cycloaddition; synthesis