One-Pot Three-Component Synthesis of Spirooxindoles Catalyzed by Hexamethylenetetramine in Water

A simple, convenient, and multicomponent strategy for synthesis of spirooxindole derivatives has been developed. This strategy provides a rapid access to construct a diversity-oriented library of spirooxindoles by using three simple and readily available isatin, malononitrile or cyanoacetic ester, and 1,3-dicarbonyl compound catalyzed by hexamethylenetetramine in water.