Dinuclear zinc-catalyzed asymmetric Friedel-Crafts alkylation/cyclization of 3-aminophenols with α,α-dicyanoolefins.

An enantioselective Friedel-Crafts alkylation/cyclization tandem reaction of 3-aminophenols with α,α-dicyanoolefins has been performed successfully using a chiral dinuclear zinc catalyst, leading to a range of chiral 2-amino-4-chromenes (up to 98% yield and >99% ee). To the best of our knowledge, this is the first asymmetric example of the dinuclear zinc-catalysed functionalization of aromatic C(sp)-H bonds.