A versatile approach to oligostilbenoid natural products - synthesis of permethylated analogues of viniferifuran, malibatol A, and shoreaphenol

A highly practical route to oligostilbenoid natural products is described. A regioselective Bi(OTf)(3)-catalyzed cyclodehydration provided ready access to 3-arylbenzofuran. Pd-catalyzed direct C-H activation of benzofuran and subsequent cross-coupling with aryl halide was successfully implemented for the introduction of aryl group at the C2 position of benzofuran. Further manipulation of the 2,3-diarylbenzofuran led to the efficient total synthesis of permethylated analogues of viniferifuran, malibatol A, and shoreaphenol.