An Access to Highly Functionalized Dihydrobenzofuran Spirooxindole Scaffolds
Daqian Wang1, Jing Sun1, Ying Han1
1College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
Abstract:
We have developed an efficient protocol for the construction of polycyclic dihydrobenzofuran spirooxindole scaffolds via base promoted cascade annulation of Morita-Baylis-Hillman (MBH) carbonates of isatins with ortho-hydroxychalcones or ortho-hydroxy-β-nitrostyrenes. The complex polycyclic compounds were conveniently synthesized in satisfactory yields and with high diastereoselectivity. This protocol provides a swift and convenient approach for the assembly of diverse highly functionalized dihydrobenzofuran spirooxindoles and also features broad substrate scope, high molecular convergence, and excellent atomic economy.
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