Manganese-Catalyzed\nCycloalkene Ring Expansion Synthesis\nof Azaheterocycles

Herein, a Mn catalytic protocol has been developed for\nthe cycloalkene\nring expansion synthesis of azaheterocycles, allowing broad-substrate-scope\naccess to pyridine and isoquinoline derivatives. The initial monoaddition\nof an azidyl radical to alkene and further as-generated C-radical\naddition to O<sub>2</sub>, followed by intramolecular rearrangement\nand aromatization, showcase a distinct Mn-catalyzed radical reactivity\nmode. The reaction features a short reaction time and a broad substrate\nscope, with applications demonstrated in complex structure elaboration\nand gram-scale vismodegib synthesis.