Copper Catalyzed Intramolecular N‑Arylation of Ketene Aminals at Room Temperature: Synthesis of 2‑Amino-3-cyanoindoles

Various
2-amino-3-cyanoindoles are synthesized through copper catalyzed
intramolecular N-arylations of ketene aminals at room temperature
for the first time with 60–99% yields within 0.1–2 h.
Controlled regioselective N-arylations of unsymmetrical ketene aminals
are also studied. Further, a new double heteroannulation approach
is demonstrated for the synthesis of 11-aminoindolo­[2,3-b]­quinolines from acyclic and nonheterocyclic precursors.