The asymmetric Povarov reaction of N-arylimines with 2- and 3-vinylindoles has been developed using a chiral phosphoric acid ((S)-TRIP) as catalyst. The peculiar reactivity of vinylindoles allowed also the disclosure of a Povarov Friedel–Crafts sequence, and the trapping of the reaction intermediate with nucleophilic species, thus providing a versatile platform for the preparation of highly enantioenriched indole derivatives.
Convenient Synthesis of Tetrahydro-γ-carbolines and Tetrahydroquinolines through a Chemo- and Regioselectivity Switch by a Brønsted Acid Catalyzed, One-Pot, Multicomponent Reaction
An efficient, one-pot, multicomponentreaction of aldehydes 1, p-methoxyaniline (2a), and 2-vinylindoles 3 was developed. This approach provides a practical approach to synthetically and biologically significant tetrahydro-γ-carboline and tetrahydroquinoline derivatives in good yields through a chemo- and regioselectivity switch, which can be tuned by simply changing the substituent on the indole component