Organocatalytic Enantioselective Synthesis of Tetrahydro‐Furanyl Spirooxindoles via [3+2] Annulations of 3‐Hydroxyoxindoles and Cyclic Ketolactams

Abstract Asymmetric construction of pharmacologically interesting tetrahydrofuranyl spirooxindole frameworks has been achieved through organocatalytic [3+2] annulations of the readily available 3‐hydroxyoxindoles and pyrrolidone‐derived cyclic ketolactams. A variety of chiral spiro tetrahydrofuranyl products, which contain four contiguous stereocenters including two tetrasubstituted carbon centers, have been rapidly synthesized with remarkable results (up to 99% yield, >95:5 dr, and 99:1 er). Synthetic derivatization of the hemiketal moiety enables the installation of various halogen atoms into the structurally complex molecules in a stereospecific manner. Preliminary screening of anticancer bioactivity was performed, and 4 w showed obvious inhibitory capacity to the proliferation on a panel of cancer cell lines. magnified image