Nickel-Catalyzed Ipso-Cross-Coupling of Homopropargyl Bromides with Aryl/Vinyl Electrophiles

A Ni/PyBCam-catalyzed protocol enables regioselective coupling at the ipso-carbon of homopropargyl bromides with aryl/vinyl electrophiles. This mild method utilizes bench-stable partners to access functionalized 1,4-biaryl and 1-aryl-4-vinyl internal alkynes─valuable synthetic building blocks. Mechanistic studies reveal initial homopropargyl-Ni formation, diverging from classical aryl-alkyl coupling pathways.