Au(I) /Brønsted Acid Relay-Catalyzed Benzannulation Reaction of Alkynylbenzaldehydes and Styrenes for the Synthesis of Substituted Naphthalenes

We report herein an Au(I) /Brønsted acid relay-catalyzed tandem benzannulation reaction of alkynylbenzaldehydes and styrenes for the synthesis of substituted naphthalenes. This reaction sequence involves Au(I)-catalyzed alkyne cycloisomerization, oxa-[4 + 2]-cycloaddition, α-ketol rearrangement, and aromatization to access substituted naphthalenes in moderate-to-good yields. The resulting substituted naphthalenes are further subjected to Brønsted acid catalysis, promoting Friedel-Crafts reactions to form chrysene derivatives in excellent yields.