Highly Efficient Construction of Bisspirooxindoles Containing Vicinal Spirocenters through an Organocatalytic Modified Feist–Bénary Reaction

We have developed an organocatalytic modified Feist-Bénary reaction of cyclic dicarbonyl compounds, isatins and cyclic α-bromo dicarbonyl compounds. This method affords bisspirooxindole-fused dihydrofurans containing two vicinal spiro centers. To the best of our knowledge, employing cyclic α-halo dicarbonyl compounds for the synthesis of bisspirooxindole-fused dihydrofurans has not been previously reported.