Iron-catalyzed indolo[2,3-c]quinoline synthesis from nitroarenes and benzylic alcohols/aldehydes promoted by elemental sulfur

Abstract

An iron-catalyzed strategy for the rapid synthesis of indolo[2,3-c]quinolines has been developed. This cascade reaction involving alcohol oxidation, nitro reduction, and oxidative annulation was achieved in a one-pot. The present protocol was started from mono-functionalized indoles and readily available benzylic alcohols/aldehydes, affording a variety of functionalized indolo[2,3-c]quinolines in satisfactory yields.