Sequential C–H and C–C Bond Cleavage: Divergent Constructions of Fused N‑Heterocycles via Tunable Cascade

Streamlining the generation of diverse highly functionalized molecules from abundant feedstocks holds great synthetic promises and challenges in pharmaceutical and material discovery. Herein, we report a tunable selectivity in multiple cascade reactions for the divergent assembly of fused N-heterocycles, comprising sequential activation of C–H and C–C bonds. Isolatable indene-type intermediates might be responsible for the generation of densely substituted fused pyridines, azepines, and azafluorenones products. The tolerance of strongly coordinating N-heterocycles, and those readily applicable for the late-stage modifications of pharmaceuticals and material molecules precursors, further demonstrated the synthetic robustness of this transformation.