Catalytic Enantioselective Allenoate–Alkene [2 + 2] Cycloadditions

Catalytic enantioselective [2 + 2] cycloadditions between allenoates and alkenes is disclosed. The method functions well for a variety of alkenes, and the products are generated with excellent levels of enantioselectivity. One of the most significant aspects of the present method is that unactivated alkenes are suitable substrates for this method, which is distinctly different from nearly all other catalytic enantioselective [2 + 2] cycloaddition methods.