Dipole-LUMO/Dipolarophile-HOMO Controlled Asymmetric Cycloadditions of Carbonyl Ylides Catalyzed by Chiral Lewis Acids

We have found the first successful example of reverse-electron-demand dipole-LUMO/dipolarophile-HOMO controlled cycloaddition reactions between carbonyl ylides, which were generated from o-methoxycarbonyl-alpha-diazoacetophenone and their acyl derivatives as precursors, and vinyl ether derivatives with high levels of asymmetric induction (97-77% ee) using chiral 2,6-(oxazolinyl)pyridine-Eu(III) or binaphthyldiimine-Ni(II) complexes as chiral Lewis acid catalysts.