Preparation and Characterization of Nano-coc-OSO₃H as a Novel Nanocatalyst for the One-Pot Synthesis of Spirooxindoles

Abstract

Chlorosulfonic acid supported on coconut shell (nano-coc-OSO₃H) as an efficient and novel nano catalyst for one-pot synthesis of spirooxindoles via three-component condensation of isatin derivatives, enolizable systems (dimedone, cyclohexadione, cyclopantadione) and malononitrile. Nano-coc-OSO₃H was synthesized and characterized via FT-IR, TGA/DTG, XRD, EDX, FESEM and TEM techniques. It is rapid and efficient catalyst for one-pot synthesis of the biologically important spirooxindole derivatives. The significant features of this methodology are nontoxic catalyst, short reaction time (15 min.), recyclability, low catalyst loading, green organic solvent (ethanol), and avoiding tedious purification step.

Keywords:

• Spirooxindoles
• isatin
• malononitrile
• enolizable system
• coconut shell

Acknowledgements

The research Council of the Islamic Azad University of Yazd is gratefully acknowledged for the financial support for this work.