Palladium‐Catalyzed Coupling of ortho‐Alkynylanilines with Terminal Alkynes Under Aerobic Conditions: Efficient Synthesis of 2,3‐Disubstituted 3‐Alkynylindoles

Two nucleophiles, one triple bond: Under aerobic conditions, palladium-catalyzed direct coupling of o-alkynylanilines and terminal alkynes took place smoothly to afford the 2,3-disubstituted 3-alkynylindoles 3 in good to excellent yields. The intermediate A was characterized and a retro-aminopalladation of B was observed for the first time.