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چکیده
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In recent years, the synthesis and applications of magnetic nanoparticles (MNPs) have attracted increasing interest in catalysis research . Among the various magnetic nanoparticles under investigation, Fe3O4 nanoparticles are arguably the most extensively studied as the core magnetic support for catalysts because of their simple synthesis, low cost, and relatively large magnetic susceptibility Fe3O4 . Cyanohydrin trimethylsilyl ethers are versatile intermediates because they can be transformed into a number of important building blocks such as α-hydroxyacids and β-hydroxyamines . One of the common methods to prepare silylated cyanohydrins is the addition reaction of trimethylsilylcyanide (TMSCN) to aldehydes in the presence of various catalysts. In this study, we present for the first time catalytic applications of magnetic nanoparticle-supported guanidine (MNPs-Guanedine) as a novel magnetically heterogeneous nanocatalyst for cyanosilylation of wide range of aldehydes in CH2Cl2 at room temperature The MNPs-Guanedine was prepared according to the procedure shown in Scheme 2. The catalyst has been characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR) are shown in Figure1 and thermogravimetric analysis (TGA) In conclusion, we have prepared the first MNPs-guanedine as robust and efficient catalyst for cyanosilylation of aldehydes with good to high yield of products under mild conditions. The characteristic aspects of this nanocatalyst are rapid, simple and efficient separation by using an appropriate external magnet, which minimizes the loss of catalyst during separation and reusable for several cycles. In addition, it couples the advantages of heterogeneous and homogeneous systems, which make them as promising materials for industrial
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