Regioselective Access to Structurally Diverse Coumarin Analogues through Iron‐Catalysed Annulation Reactions

Abstract

A highly efficient iron‐catalysed propargylation/alkyne oxacyclization/isomerization strategy is described. Biologically active furo[3,2‐ c ]coumarins and pyrano[3,2‐ c ]coumarins are expeditiously assembled in moderate to good yields and with a broad substrate scope. The regioselective access to different coumarins is mainly dependent on the terminal group of the secondary propargylic alcohol.