A Cu/Pd Cooperative Catalysis for Enantioselective Allylboration of Alkenes

A cooperative Cu/Pd-catalyzed asymmetric three-component reaction of styrenes, B₂(pin)₂, and allyl carbonates was reported. This reaction, in the presence of chiral CuOAc/SOP and achiral Pd­(dppf)­Cl₂ catalysts, occurs smoothly with high enantioselectivities (up to 97% ee) . The allylboration products, which contain alkene (or diene) unite and alkylboron group, are easily functionalized. The utility of this protocol was demonstrated through the synthesis of an antipsychotic drug, (−)-preclamol