Dess-Martin periodinane promoted oxidative coupling of Baylis-Hillman adducts with silyl enol ethers: a novel synthesis of cis-fused dihydropyrans

Baylis-Hillman adducts undergo smooth oxidative Mukaiyama-Michael addition and a subsequent cyclization with silyl enol ethers in the presence of Dess-Martin periodinane (DMP) and pyridine under mild reaction conditions to afford a new class of dihydropyran derivatives in good yields with high diastereoselectivity. This is the first report on the preparation of cis-fused dihydropyrans from Baylis-Hillman adducts and silyl enol ethers