Synthesis of Spiro Pyran by using Silica-Bonded N-Propyldiethylenetriamine as Recyclable Basic Catalyst

In some natural products isatin and its derivatives used as a precursors due to the wonderful biological characteristics. In the biological research, we can raise the biocidal activity with the entity of two or more various heterocyclic moieties in one molecule. In continuation of our work to develop new catalysts for organic transformations, here we are reported the preparation of spirooxindole derivatives. Basis of our method, using of the isatin reaction and malononitrie. Also, in this method, impressible and recyclable catalysts are silica-bonded N-propyldiethylenetriamine and silica-bonded N-propyl diethylenetriamine sulfamic acid. Result showed that, this method has many advantages like as simple work-up method, clean and facile procedure, and environment friendly circumstance.