Design of a new class of chiral C2-symmetric dipyridylmethane ligands and their application in asymmetric catalysis

A new class of chiral C2-symmetric dipyridylmethane ligands was prepared from naturally occurring monoterpenes, according to a method based on a double Michael–azaannellation–aromatization sequence. These ligands were assessed in the enantioselective palladium-catalyzed allylic alkylation of 1,3-diphenylprop-2-enyl acetate with dimethylmalonate and in the copper-catalyzed cyclopropanation of styrene with ethyl diazoacetate. Enantioselectivity up to 88% ee was obtained.