Enantioselective synthesis of pyrroloquinolines via a three-component Povarov reaction with aminoindoles

A three-component Povarov reaction has been established to enantioselectively construct pyrroloquinolines in the presence of a chiral phosphoric acid. This one-pot process affords the structurally important pyrroloquinolines exclusively as a single diastereomer in 53 to >99% yields with 55 to 99% ee. This catalytic protocol provides concise access to enantioenriched pyrroloquinolines, enabling the regiospecific construction of three types of annulated cycles in the carbocyclic ring of indole. This approach presents an alternative methodology for the straightforward functionalization of the carbocyclic ring of indoles.