Catalytic Enantioselective [2 + 2]-Cycloaddition Reaction of 2-Methoxycarbonyl-2-cyclopenten-1-one by Chiral Copper Catalyst.

Abstract A new catalytic system for enantioselective [2+2]-cycloaddition reaction of 2-methoxycarbonyl-2-cyclopenten-1-one with thioacetylene derivatives is described. The use of a catalytic amount (20–30 mol%) of copper(II) salt with chiral bis-pyridine ligand was found to be effective in promoting the [2+2]-cycloaddition reaction, furnishing the corresponding bicyclic compound in good yield and good enantioselectivity.