Chiral Counteranion Synergistic Organocatalysis under High Temperature: Efficient Construction of Optically Pure Spiro[cyclohexanone-oxindole] Backbone

The combination of a cinchona-based chiral primary amine and a BINOL-phosphoric acid has been demonstrated as a powerful and synergistic catalyst system for the double Michael addition of isatylidene malononitriles with α,β-unsaturated ketones, to provide the novel chiral spiro [cyclohexane-1,3′-indoline]-2′,3-diones in high yields (88–99%) with excellent diastereo- and enantioselectivities (94:6–99:1 dr’s, 95–99% ee’s).