Herein, a highly efficient, scalable, and cascade [1,5] hydride transfer/cyclization method for constructing unique spirocyclic pyrazolone-pyrrolo[4,3,2- de ]quinoline structures via C(sp 3 )-H functionalization is achieved, using pyrazolones and oxindoles attached to C4 amines. This strategy represents a limited approach utilizing C-H activation to construct spirocyclic pyrazolone scaffolds with moderate to excellent reaction performance.