Sodium Salts of Anionic Chiral Cobalt(III) Complexes as Catalysts of the Enantioselective Povarov Reaction

The sodium salts of anionic chiral cobalt(III) complexes (CCC−Na+) have been found to be efficient catalysts of the asymmetric Povarov reaction of easily accessible dienophiles, such as 2,3‐dihydrofuran, ethyl vinyl ether, and an N‐protected 2,3‐dihydropyrrole, with 2‐azadienes. Ring‐fused tetrahydroquinolines with up to three contiguous stereogenic centers were thus obtained in high yields, excellent diastereoselectivities (endo/exo up to >20:1), and high enantioselectivities (up to 95:5 e.r.).