K 2 CO 3 -Catalyzed (3 + 2) Cycloaddition Reaction of N -2,2,2-Trifluoroethylisatin Ketimines with Azodicarboxylates: Access to Spirooxindoles Containing Trifluoromethyl-1,2,4-triazolines.

Potassium carbonate-catalyzed (3 + 2) cycloaddition reaction between N -2,2,2-trifluoroethylisatin ketimines and azodicarboxylates has been developed, constructing a series of novel N -heterocycle infused spirooxindoles in good to excellent yields (up to 98%) under milder conditions. The presence of both biologically active oxindole and trifluoromethyl-1,2,4-triazoline moieties in these novel spirocyclic compounds would provide new lead structures in the discovery of heterocyclic compounds with potential pharmaceutical activities.