Highly enantioselective Friedel–Crafts alkylation of indoles and pyrrole with β,γ-unsaturated α-ketoesters catalyzed by heteroarylidene-tethered bis(oxazoline) copper complexes

Abstract

The simple and cheap chiral catalyst, heteroarylidene-tethered Ph-bis(oxazoline)–Cu(OTf)₂, can efficiently catalyze the asymmetric F–C alkylation of indoles and pyrrole with β,γ-unsaturated α-ketoesters. The 3-indolyl adducts were obtained in up to >99% ee. Moreover, the 2-pyrrolyl adducts were achieved in up to 92% ee for the first time.