Enantioselective synthesis of spirooxindole-pyran derivatives via a remote inverse-electron-demand Diels–Alder reaction of β,γ-unsaturated amides

Abstract

Novel construction methods for obtaining 3,4′-pyran spirooxindole heterocyclic skeletons have always been the focus of attention. Herein, we report a highly enantioselective inverse-electron-demand oxa-Diels–Alder cycloaddition reaction of a β,γ-unsaturated pyrazole amide and a N-diphenyl isatin-derived oxodiene using a bifunctional catalyst. In addition, large-scale experiments confirmed the reliability of the reaction. The resultant products of this study can be further transformed.