MOF-199 as an Efficient Metal Organic Framework Catalyst for the Synthesis of Spiro[Indoline-3,4′-Pyrano[2,3-c]Pyrazole] Derivatives

Abstract

Metal organic frameworks are frameworks of 1–3 D formed by the interaction between metal ions/clusters and organic molecules. The high specific surface area and large pore volume of these molecules render them as ideal candidates for catalysis applications. A metal-organic framework (MOF-199) has been synthesized by facile chemical method and characterized by infrared (IR) spectroscopy, proton nuclear magnetic resonance (¹H NMR), transmission electron microscopy (TEM) and energy dispersive X-ray (EDS) technique. In this study an efficient eco-friendly procedure for the synthesis of spiro[indoline-3,4′-pyrano[2,3-c]pyrazole] derivatives has been developed through a four-component condensation of isatin and its derivatives, hydrazine hydrate, ethyl acetoacetate, and malononitrile/ethyl cyanoacetate, in the presence of catalytic amount of MOF-199 in H₂O at room temperature. The advantages of this protocol include mild reaction condition, green, and nontoxic solvent, high yield, easy separation, reusability of the catalyst and operational simplicity.

Keywords:

• Spiro[indoline-3,4′-pyrano[2,3-c]pyrazole
• metal-organic framework (MOF-199)
• aqueous medium
• multi-component reaction

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

Authors are thankful to the research Council Department of Chemistry of Hakim Sabzevari University and financial support for this work.