Green synthesis of pyranopyrazoles using Tungestic acid/Zr bio-based MOF as an efficient heterogeneous catalyst

Journal of Chemical Reactivity and Synthesis

دوره 9، شماره 3، آبان 2019، صفحه 22-38   

نوع مقاله: Research Article

نویسندگان

Shima Khademi¹؛ Saeed Zahmatkesh^{* 2}؛ Alireza Aghili³؛ Rashid Badri⁴

¹Department of Chemistry, Khouzestan Science & Research Branch, Islamic Azad University, Ahvaz, Iran

²Department of Science, Payame Noor University (PNU), 19395-4697, Tehran, Islamic Republic of Iran

³Department of Polymer Engineering, Shiraz Branch, Islamic Azad University, Shiraz, Iran

⁴Department of Chemistry, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran

چکیده

This reported work aims to fabricate an eco-friendly Zr bio-based MOF as a new magnetic nanocatalyst based on the immobilization of tungstic acid onto new design robust, cost-effective, green and scalable Zirconium-L-aspartate amino acid metal-organic framework (MOF)-grafted L-(+)-tartaric acid stabilized magnetite nanoparticles (Fe₃O₄/Tart-NPs) was successfully prepared by two successive hydrothermal method. This catalyst was characterized by FT-IR, XRD, FE-SEM and TGA-DTA  analysis. This catalyst is outstanding to prepare l ‐ (4 ‐ phenyl) ‐ 2,4 ‐ dihydropyrano [2,3 ‐ c] pyrazole derivatives in aqueous media due to the open metal sites, high and steady proton conductivity in the zirconium-MOF, MIP-202(Zr), MOF and also due to Brønsted acid properties of tungstic acid. This acidic catalyst can easily be extracted by an outward magnetic field after completion of the reaction without any deactivation or selectivity loss. The products were characterized by spectroscopic analysis (¹HNMR,¹³CNMR and also  FTIR). The optimized reaction conditions and a possible reaction mechanism is outlined.

کلیدواژه‌ها

Tungstic acid؛ Nano-catalyst؛ Pyranopyrazole derivatives