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چکیده
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Schiff-base materials are known ligands for the coordination of metal ions and the synthesis of various stable and useful complexes. Therefore, herein, a novel Schiff-base compound {2,2'-((1E,11E)-2,5,8,11-tetra azadodeca-1,11-diene-1,12-diyl) bis (4-bromophenol)} was introduced that formed from condensation of triethylenetetramine (TETA) and 5-bromo-2-hydroxybenzaldehyde (5B2HB). This Schiff-base ligand was labeled as TADDbBP. Besides, mesoporous MCM-41 was synthesized using tetraethyl orthosilicate (TEOS), hydrolyzing cetyltrimethylammonium bromide (CTAB) and NaOH solution (2 M), followed by calcination at 550 ºC, and further, the silanol sites on the MCM-41’s surface were modified by 3-chloropropyltriethoxysilane (3Cl-PTES), which modified MCM-41 was labeled as 3-Cl-Pr@MCM-41. In the next step, the synthesized TADDbBP (as Schiff-base ligand) was grafted on 3-Cl-Pr@MCM-41, which was labeled as TADDbBP@MCM-41, and further, it was coordinated with samarium ions (which was labeled as Sm-TADDbBP@MCM-41 nanocatalyst) using Sm(CH3COO)3. It is the first report on the production of Sm-TADDbBP@MCM-41 nanocatalyst, this nanocatalyst was characterized by TEM, SEM, EDX, elemental mapping, BET method, ICP, XRD, and TGA techniques. In the final step, the catalytic performance of Sm-TADDbBP@MCM-41 nanocatalyst has been checked in the homo-selective producing of tetrazoles through [2+3] cycloaddition of benzonitriles and sodium azide (NaN3) in PEG-400 as available, nontoxic, green and safe solvent. This nanocatalyst provides excellent selectivity in the synthesis of tetrazoles. In addition, Sm-TADDbBP@MCM-41 nanocatalyst can be separated and recycled for several cycles without significant reactivation or metal leaching.
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