Heterocycle‐to‐Heterocycle Route to Quinoline‐4‐amines: Reductive Heterocyclization of 3‐(2‐Nitrophenyl)isoxazoles

A variety of quinoline‐4‐amines were synthesized from substituted 3‐(2‐nitrophenyl)isoxazoles utilizing Zn0 or Fe0 dust and HOAc using a reductive heterocyclization process. The starting isoxazoles were synthesized from readily available starting materials. A brief survey of functional groups tolerated in this reductive heterocyclization was performed and several 10‐amino‐3,4‐dihydrobenzo[b][1,6]naphthyridin‐1(2H)‐one and 9‐amino‐3,4‐dihydroacridin‐1(2H)‐one examples were synthesized.