Gold(I)-catalyzed cascade cyclization reaction: highly regio- and diastereoselective intermolecular addition of water and alcohols to epoxy alkynes.

We have developed a novel access to ketal skeletons through a highly regio- and diastereoselective intermolecular addition of water and alcohols to alkynyl epoxides catalyzed by gold(I). This procedure involves a domino three-membered ring-opening, 6-exo-cycloisomerization, and subsequent intra- or intermolecular nucleophilic addition to a double-bond sequence.