Gold(I)‐Catalyzed Hydration Reactions of Diynes to Access Tetrasubstituted Cyclohexenones

Tetrasubstituted 2‐carboalkoxy‐3‐substituted‐cyclohexenones are powerful building blocks for the synthesis of a variety of bioactive target molecules. Their preparations require multisteps sequence involving the use of stoichiometric quantities of various reagents, while the catalytic approaches are limited to trisubstituted cyclohexenones. Herein, an efficient catalytic approach based on gold(I)‐catalysis starting from unsymmetrical diynyl mono‐ester or symmetrical diynyl di‐ester substrates is described. The carbon chain linking the two alkyne functions can bear two or one substituent, or evenbe unsubstituted. Regardless of the nature of the substrates and independently of its substitution, the cyclohexenone derivatives are cleanly produced.