Catalytic enantioselective and site-specific Friedel−Crafts alkylation of 4-aminoindoles with β,γ-alkynyl-α-ketoimines for the synthesis of C7-functionalized indoles

Chiral phosphoric acid-catalyzed enantioselective Friedel−Crafts alkylation of 4‑aminoindoles with β,γ-alkynyl-α-ketoimines has been developed. A range of optically pure C7-functionalized indoles bearing a quaternary α-amino acid or trifluoromethylated tetrasubstituted alkylamine motif...