Catalytic Asymmetric Synthesis of Chiral Bis(indolyl)methanes Using a Ts-PyBidine–Nickel Complex

A chiral tosyl-substituted bis­(imidazolidine)­pyridine Ts-PyBidine–nickel complex was an efficient catalyst for Friedel–Crafts reaction of indoles with methylene indolinones to give bisindolylmethane compounds having differently oxidized indole units with high enantioselectivities. Alkylation of the products proceeded smoothly in a highly diastereoselective manner, providing an all-carbon quaternary carbon center without significant loss of enantiomeric excess.