Palladium-Catalyzed Intramolecular C(sp²)‑H Imidoylation for the Synthesis of Six-Membered N‑Heterocycles

Abstract

A new strategy for the construction of phenanthridine and isoquinoline scaffolds, starting from arenes containing a pending isocyanide moiety under palladium catalysis, has been developed. This process involves sequential intermolecular isocyanide insertion to an aryl palladium­(II) intermediate and intramolecular aromatic C–H activation as key steps. Alkyl palladium­(II) intermediate lacking β-hydrogen is also applicable to this reaction, generating unique bisheterocyclic scaffolds with three C–C bonds being formed consecutively