Catalytic enantioselective Friedel–Crafts alkylation at the 2-position of indole with simple enones

A procedure for the enantioselective alkylation of indole at the 2-position with simple non-chelating enones is described for the first time. Reaction between 4,7-dihydroindole and enones in the presence of zirconium(IV)–BINOL complexes, followed by a p-benzoquinone oxidation gives indoles alkylated at the 2-position with good yields and moderate enantioselectivities.