Total Synthesis of the Oligostilbenes Anigopreissin A and Fuliginosin A

A convergent synthesis of the natural stilbenes anigopreissin A and fuliginosin A is presented. The key step involves a copper-catalyzed heteroannulation between an oxime acetate and a 4-substituted 1,3-cyclohexanedione, yielding a suitably substituted benzofuran-4-one via a mechanism that does not involve radicals. The use of methoxymethyl (MOM) ethers as protecting groups ensures the expedited completion of the sequence. The scope established for the heterocyclization suggests that this approach may be adapted to synthesize additional stilbenes.