Au(I)-Catalyzed Enantioselective 1,3-Dipolar Cycloadditions of Münchnones with Electron-Deficient Alkenes

The first catalytic enantioselective 1,3-dipolar cycloaddition of münchnone dipoles with electron-deficent alkenes is described. The reaction is catalyzed by chiral bis(phosphine)gold(I) benzoate complexes and provides Δ1-pyrrolines with excellent regio-, diastereo-, and enantioselectivity. The reaction is proposed to proceed through a 1,3-dipole generated by deprotonation of a gold(I)-activated azlactone.