Highly enantioselective Diels-Alder reaction of Danishefsky-type diene and electron-deficient olefins catalyzed by an Yb(III)/chiral bis-urea complex

The synthesis and utility of the novel axially chiral bis-urea ligand BINUREA are described. A complex of this urea ligand with ytterbium triflate and DBU can be used in the catalytic enantioselective Diels-Alder reaction of Danishefsky-type diene and electron-deficient olefins to give the adducts in good to excellent yield and enantiomeric excess (ee).