Gold(I)‐Catalyzed Domino Reaction: An Access to Furooxepines

We report herein the synthesis of [7,5]-fused bicyclic acetals, also named furooxepines through a gold(I)-catalyzed domino reaction. During this transformation, two molecules of homopropargyl alcohol react together, in a sequence including an intramolecular hydroalkoxylation, condensation, a 1,6-enyne cycloisomerization, acetalization and an isomerization. This gold(I)-catalyzed domino reaction allow the formation of three bonds, two heterocycles and a tetrasubstituted carbon stereocenters in a one-step operation with 100% atom economy. Post-functionalizations allow the formation of tetrahydrofurans.