Photoinduced Pd-Catalyzed Selective 1,4-Dicarbofunctionalization of 1,3-Butadiene with Alkyl or Aryl Bromides and Oxindoles

Abstract The dicarbofunctionalization of 1,3-butadiene provides rapid access to complex allyl compounds in organic synthesis. Here we report a photoinduced palladium-catalyzed three-component coupling that enables selective 1,4-dicarbofunctionalization of 1,3-butadiene with alkyl or aryl bromides and oxindole nucleophiles. This transformation utilizes photoexcited Pd(0) species to activate both substrate classes via single-electron transfer, accommodating radicals of distinctly different electronic nature—nucleophilic alkyl radicals and electrophilic aryl radicals—through tailored reaction conditions. Under mild conditions, the protocol delivers 80 oxindole derivatives in good yields (up to 93%) and regioselectivities (up to >20:1 r.r.), providing efficient access to bioactive oxindole scaffolds.