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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 °C, 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. This 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. [ABSTRACT FROM AUTHOR]

In first part, boehmite nanoparticles were synthesized using aqueous solutions of NaOH and Al(NO3)3 ⋅ 9H2O. Then, it surface was modified by 3‐choloropropyltrimtoxysilane, and further 1,3‐bis(pyridin‐3‐ylmethyl)thiourea was anchored on the modified boehmite nanoparticles. In the final step, a neodymium complex was stabilized on its surface (Nd‐bis(PYT)@boehmite NPs). The obtained nanoparticles were characterized by TGA, BET, ICP, EDS, WDX, SEM, and XRD techniques. In the second part, Nd‐bis(PYT)@boehmite NPs were employed as an efficient, recoverable, and organic‐inorganic hybrid nanocatalyst in the homo‐selective synthesis of tetrazole compounds. The chemoselectivity of Nd‐bis(PYT)@boehmite NPs was studied in the [3+2] cycloaddition of phthalonitrile and sodium azide (NaN3). This catalyst is stable and has heterogeneous nature therefore it can be recovered and used again for several consecutively run without any re‐activation [ABSTRACT FROM AUTHOR]

Catalyst species are an important class of materials in chemistry, industry, medicine and biotechnology. Also, waste recycling is an important process in green chemistry and economic efficiency. Therefore, in order to recycle waste, biochar nanoparticles were prepared from chicken manure. Then, the biochar nanoparticles were magnetized under a green and environmentally friendly method. Finally, the surface of the magnetic biochar nanoparticles was modified and further they were applied as a novel support for fabrication of nickel as a homoselective and reusable catalyst in organic reactions. The structure of this organic–inorganic catalyst has been characterized by N2 adsorption–desorption isotherms, and the SEM, EDS, WDX, XRD, TGA, AAS, FT-IR and VSM techniques. This magnetically recyclable catalyst was used in the homoselective synthesis of tetrazole and pyranopyrazole derivatives. This catalyst can be reused several times without significant loss of its catalytic efficiency. The heterogeneity and stability of this nanocatalyst were studied by hot filtration and the AAS technique. Also, the reused catalyst was characterized by the SEM, EDS, AAS and BET techniques. [ABSTRACT FROM AUTHOR]