Enantioselective Synthesis of Cyclopentadienes by Gold(I)-Catalyzed Cyclization of 1,3-Dien-5-ynes

An asymmetric synthesis of elusive chiral cyclopentadienes has been developed by gold(I)-catalyzed alkoxycyclization of 1,3-dien-5-ynes. The application of these substrates in completely diastereoselective Diels-Alder cycloaddition reactions, which can be carried out in one pot from achiral 1,3-dien-5-ynes, allows the preparation of highly functionalized products bearing five stereogenic centers with high enantiomeric excesses.