%0 Journal Article %T Urea immobilized silica-coated Fe3O4 MNPs as a heterogeneous magnetic nanocatalyst for the synthesis of 2-amino-4H-benzo[b]pyran derivatives %J Asian Journal of Nanoscience and Materials %I Sami Publishing Company %Z 2645-775X %A Yadollahzadeh, Khadijeh %D 2022 %\ 05/01/2022 %V 5 %N 2 %P 144-158 %! Urea immobilized silica-coated Fe3O4 MNPs as a heterogeneous magnetic nanocatalyst for the synthesis of 2-amino-4H-benzo[b]pyran derivatives %K Fe3O4@SiO2@(CH2)3 %K Urea Magnetic Nanoparticle Multicomponent reaction Pyran derivatives %R 10.26655/AJNANOMAT.2022.2.6 %X In this work, a novel urea immobilized silica-coated Fe3O4 MNP (Fe3O4@SiO2@(CH2)3-Urea) as a magnetically recoverable and metal-free nanocatalyst was designed and synthesized, and characterized using FT-IR, XRD, FE-SEM, TEM, EDX, and VSM. This system was explored in a three-component reaction to synthesize 2-amino-4H-benzo[b]pyran derivatives of dimedone, malononitrile, and aromatic aldehydes in ethanol at 80 °C. This new method has numerous merits, such as using a green and nontoxic catalyst, excellent yield, shorter reaction time, broad substrate scope, operational simplicity, and functional group compatibility. Moreover, the synthesized nanocatalyst was recovered by a magnetic field, and it was reused eight times without any appreciable change in the catalytic activity. %U https://www.ajnanomat.com/article_150256_63d07cc7107e33f0c9fbe71c6e8875c3.pdf