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چکیده
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Chiral amines play an important role in biological activities, pharmaceutical, agricultural and natural products. They are very important intermediates in the synthesis of some drugs and chemicals and act as important ligands in the synthesis of chiral compounds also. One method concerning the preparation of chiral amines is the increase of aryl group to imine using organometal catalysts 1. Among various catalytic systems, Pd/Fe3O4 magnetic nanocatalysts possess the properties of both homogeneous and heterogeneous ones and in addition have several advantages, such as fewer metal residues in the products, a recyclable/reusable catalytic system2. The Pd/Fe3O4 catalytic system increases selectivity and reactivity of reaction and easily separated from the mixture with an external magnetic field3, 4. In this study, the preparation of chiral secondary Amines 3 through the arylation of protected imines 1 and organic boron compounds 2 in the presence of nanomagnetic catalysts Pd/Fe3O4 and chiral phosphine ligands 5 was examined. The use of Pd/Fe3O4 nanomagnetic catalyst with the possibility of recovery and reuse of the nanomagnetic catalyst coordinated with phosphine ligands is one of the highlights of this reaction (Scheme1). The structure of chiral products is characterized by melting point, IR, 1H NMR, and 13C NMR spectroscopies. The enantiomeric excess (ee) of chiral products is also detected by the polarimeter. The structure and morphology of prepared nanocatalyst Pd/Fe3O4 were characterized by EDAX, SEM, FT-IR, TEM, and TGA-DTA.
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