The development of non-natural enzymatic catalysis is important for multicomponent tandem organic transformations. However, the delicate acting environments biological enzymes still present some challenges in synthesis spirooxindole skeleton via catalysis. To address these issues, a lipase-catalyzed method was developed frameworks. Using easily available isatins, cycloketones, and malononitrile...

Dynamic kinetic asymmetric transformation (DYKAT) reactions of racemic diastereomer mixtures that afford the products as essentially single diastereomers with high enantioselectivities are described. We demonstrated DYKAT in diastereo- and enantioselective synthesis spirooxindoles bearing furan-fused rings. The starting materials DYKAT, dihydrobenzofuranone derivatives, were synthesized mixture...

This work describes the synthesis of enantioenriched spiro compounds, incorporating the azetidine and the oxindole motifs. The preparation relies on a formal [2 + 2] annulation reaction of isatin-derived N-tert-butylsulfonyl ketimines with allenoates. The asymmetric induction is secured by an organocatalytic strategy, exploiting a bifunctional cinchona-type β-isocupridine-based catalyst. Some p...

The assembly of complex spirocyclopentaneoxindoles via a novel organocatalytic iminium-enamine cascade process is reported. Reactions between 3-substituted oxindoles and α,β-unsaturated aldehydes catalyzed by second generation prolinol ethers provided the desired products in high yield with excellent levels of enantioselectivity in a single step.