Two Distinct Carbocyclizations of (2‐Formylphenyl)prop‐2‐yn‐1‐yl acetates to Form Substituted 1H‐indene Derivatives and 4‐Acetoxy‐3‐hydroxy‐2‐naphthoates. Cooperative Catalysis using Au(I)/H2O Dual Catalysts

Abstract Gold‐catalyzed cyclizations of (2‐formylphenyl)prop‐2‐yn‐1‐yl acetates afford two distinct cyclization products. In the case of substrates bearing a alkyl or arylalkynyl group, 2‐carbonyl‐ 1H ‐indene derivatives were obtained whereas substrates bearing an electron‐withdrawing alkynoate or alkynone group, distinct 4‐acetoxy‐3‐hydroxy‐2‐naphthoates were produced efficiently. Our mechanistic analysis indicates that H 2 O is not only a nucleophile but also a catalyst for both carbocyclizations. magnified image