A palladium-catalyzed three-component [2 + 3 + 1] domino annulation among 3-iodochromones, αbromoacetophenones, and norbornene is presented, affording various chromone-containing polycyclic compounds bearing fused/spiro/bridged-ring systems. For the first time, the 2,2bifunctionalization of norbornene was realized in palladiumcatalyzed domino reaction. This cyclization characterizes three new bonds (two C−C and one C−O) in a single operation and produces nontrivial spiro-norbornane fragments in comparison with a traditional palladium-catalyzed process involving norbornene.

A palladium‐catalyzed [2+2+1] annulation among 3‐iodochromones, benzyl bromides, and norbornene has been developed. This annulation consists of a domino sequence involving Heck coupling/C(sp2)−H activation/C(sp3)−H activation, affording a variety of complex chromone derivatives bearing five contiguous tertiary carbon centers in up to 94% yield and 99:1 dr. Interestingly, the diastereoselectivity could be switched by fine‐tuning the solvent, in which endo isomer and exo isomer were obtained using mesitylene/CH3CN and mesitylene, respectively.