Enantioselective Synthesis of 2‑Amino-1,1-diarylalkanes Bearing a Carbocyclic Ring Substituted Indole through Asymmetric Catalytic Reaction of Hydroxyindoles with Nitroalkenes

An
asymmetric catalytic reaction of hydroxyindoles with nitroalkenes
leading to the Friedel–Crafts alkylation in the carbocyclic
ring of indole is presented. The method is based on the activating/directing
effects of the hydroxy group situated in the carbocyclic ring of the
indole providing nitroalkylated indoles functionalizated at the C-4,
C-5, and C-7 positions with high yield, regio-, and enantioselectivity.
The optically enriched nitroalkanes were transformed efficiently in
optically enriched 2-amino-1,1-diarylalkanes bearing a carbocyclic
ring substituted indole.