A trinuclear Cu2Eu complex catalyzed asymmetric Friedel–Crafts alkylations of indoles with nitroalkenes

Catalytic enantioselective Friedel–Crafts alkylations of indoles and nitroalkenes were carried out by using a new heterotrimetallic Cu/Eu/Cu complex catalyst based on the simple chiral ligand, reduced Schiff base 1, to give the Friedel–Crafts adducts with up to 88% yield and 80% ee. The trimetallic catalyst is air-stable and can be formed in-situ by a facile solution self-assembly during the catalytic reaction.