A clean and expedient synthesis of spirooxindoles catalyzed by silica-sulfuric acid nanoparticles as an efficient and reusable reagent

作者：Sadeghi Bahareh^*; Pirbaluti Maryam Ghasemi; Nezhad Parinaz Farokhi; Nezhad Reza Abbasi

来源：Research on Chemical Intermediates, 2015, 41(6): 4047-4055.

DOI：10.1007/s11164-013-1509-1

• Spirooxindoles
• 5-Fluoroisatin
• Malononitrile
• Enolizable system
• Silica-sulfuric acid nanoparticles

An atom-efficient, one-pot, three-component synthetic method, using silica-sulfuric acid nanoparticles as catalyst, has been developed for preparation of biologically important spirooxindoles. The reaction involves the use of isatin or 5-fluoroisatin, malononitrile, and enolizable systems. A wide range of enolizable systems can be used in this reaction, furnishing excellent yields in a short time. The catalyst is recyclable with reproducible results without any loss of its activity. The morphology of the silica-sulfuric acid nanoparticles was observed by scanning electron microscopy. Some of the compounds were new and their structures were deduced by elemental and spectral analysis (IR, H-1 NMR, and C-13 NMR). Moreover, column chromatography and recrystallization of the products is not required because the crude products are already highly pure.

• 出版日期2015-6