Ruthenium(II)-catalyzed facile synthesis of 3-(phenylamino)-1H-indole-2-carboxylates from anilines and diazo pyruvates promoted by FeCl3

Abstract An unprecedented synthetic route towards a variety of 3-anilino-1H-indoles is accomplished from diazo pyruvates and anilines via a domino ruthenium-catalyzed annulation and subsequent iron promoted fragmentation and rearrangement. The current strategy was amenable to deliver diversely substituted indole esters, which were subjected to in vitro anti-cancer activity assessment using CCK-8 assay. Compound 4i displayed the best inhibition activity with IC50 value of 0.05 μM, triggering the initiation towards discovering promising lead compounds in the future.