Nanomagnetic NH2·MIL-101(Fe)/ED as a new highly efficient catalyst for the synthesis of thiopyran and oxospiro-indolinethiopyran derivatives

In this publication, we reported an efficient MOF-based catalytic system for the synthesis of thiopyran and oxospiro-indolinethiopyran derivatives. For the first time, magnetic NH2.MIL-101(Fe)/ED was synthesized through anchoring FeCl3 on CoFe2O4 magnetic nanoparticles surface and then 2-aminoterphthalic acid was used to form MOF structure. In the final step, metal centers were modified with ethylenediamine (ED). Different techniques such as Fourier transmission infrared spectroscopy, X-ray diffraction, Field emission scanning electron microscopy, Transmission electron microscopy, Brunauer-Emmett-Teller analysis, and Thermogravimetric analysis were used to characterize the catalyst structure. Also using X-ray crystallography, the structure of the final product was determined. Nanomagnetic NH2.MIL-101(Fe)/ED gave us a satisfactory answer, affording the corresponding products with high to excellent yields (up to 93% yield). It seems that among the other available procedures, this catalytic system provided higher final product yields which result from the superior activity of this synthesized catalyst.