Mimicking polyolefin carbocyclization reactions: gold-catalyzed intramolecular phenoxycyclization of 1,5-enynes.

PPh(3)AuNTf(2) promotes highly efficient intramolecular phenoxycyclization reactions on 1,5-enynes under mild conditions. The original tricyclic and functionalized heterocycles were isolated in good to excellent yields. The 6-endo cyclization process is predominant and operates via a biomimetic cascade cation-olefin process. The efficiency of this system was further demonstrated in the cycloisomerization reaction of a 1,5,9-dienyne.