Palladium(0)-catalyzed cyclopropane C-H bond functionalization: synthesis of quinoline and tetrahydroquinoline derivatives

A series of quinoline and tetrahydroquinoline derivatives were prepared via a one-pot protocol involving intramolecular palladium(0)-catalyzed cyclopropane sp(3) C-H bond functionalization and subsequent oxidation or reduction. The reaction conditions demonstrate good tolerance for a wide range of functional groups. Evidence suggests that the reaction proceeds through C-H bond cleavage and C-C bond formation to generate a dihydroquinoline intermediate via in situ cyclopropane ring-opening.