Nickel-Catalyzed Synthesis of Benzo[ b]naphtho[1,2- d]azepine via Intramolecular Radical Tandem Cyclization of Alkyl Bromide-Tethered Alkylidenecyclopropanes.

A Ni(II)-catalyzed tandem cyclopropane ring opening and radical alkylation of the aromatic ring using unactivated alkyl bromide-tethered alkylidenecyclopropanes (ACPs) have been described in this paper. This ring-forming process exhibits a broad substrate scope with a variety of primary alkyl bromides and aromatic rings, affording diversified benzo[ b]naphtho[1,2- d]azepine derivatives in moderate-to-excellent yields under mild conditions. Plausible reaction mechanisms have been proposed on the basis of several control experiments, including the deuterium labeling examinations. Further derivatization of the obtained polycyclic product has also been performed.