Asymmetric Synthesis of Cyclopenta[3,4]pyrroloindolones via N-Heterocyclic Carbene-Catalyzed Michael/Aldol/Lactamization Cascade Reaction.

The N-heterocyclic carbene-catalyzed asymmetric Michael/aldol/lactamization cascade reaction of enals and indole-derived enones for the synthesis of functionalized cyclopenta[3,4]pyrroloindolones with four consecutive stereogenic centers has been achieved. The products were obtained in good yield with high diastereoselectivity and excellent enantioselectivity.