Palladium‐Catalyzed Decarboxylative Coupling of Alkynoic Acids with 2‐Alkynylanilines in Ionic Liquid

An efficient and reliable NHC‐palladium‐catalyzed cascade decarboxylative coupling of alkynoic acids with 2‐alkynylanilines for the rapid and straightforward assembly of synthetically valuable 3‐alkynylindole derivatives in eco‐friendly medium is described. Control experiments revealed that NHC‐Pd catalysts and base were all essential for this catalytic system. More importantly, this approach features mild reaction conditions, excellent functional group compatibility, and reasonable to excellent yields.