Enantioselective formal synthesis of (+)-precapnelladiene by chiral copper-catalyzed asymmetric [2+2]-cycloaddition reaction

Enantioselective short formal synthesis of (+)-precapnelladiene (1) was achieved from a bicyclo[3.2.0]heptane derivative, which was prepared enantioselectively by chiral copper-catalyzed [2+2]-cycloaddition reaction of 2-methoxycarbonyl-2-cyclopenten-1-one with phenylthioacetylene developed by us.