Nitrile Ylides: Diastereoselective Cycloadditions using Chiral Oxzolidinones Without Lewis Acid

Lewis acid complexation is generally required for chiral-auxiliary-controlled stereoselectivity, and chiral Lewis acid catalysis is frequently optimal for introducing asymmetry. In this work, we show that nitrile ylide cycloadditions to electron-poor acceptors attached to chiral auxiliaries proceed in high yield and stereoselectivity In the absence of Lewis acids. In contrast, chiral Lewis acids are inferior in these cycloadditions.