Magnetic Nanocomposite of Cross‐Linked Melamine Groups Decorated with Large Amounts of Gold NPs: Reduction of Nitro Compounds and Suzuki–Miyaura Coupling Reactions in Aqueous Media

Abstract

A magnetic nanocomposite was prepared based on magnetic Fe3O4 nanoparticles entrapped into a cross‐linked nitrogen rich polymer which has high loading capacity for immobilization of gold nanoparticles. The synthesized catalyst was characterized using various methods including Atomic absorption spectroscopy (AAS), Transmission electron microscopy (TEM), Fourier‐transform infrared spectroscopy ( FT‐IR), Energy‐dispersive X‐ray spectroscopy (EDX), Thermogravimetric analysis (TGA), scanning electron microscope (SEM), Brunauer–Emmett–Teller (BET), VSM and X‐ray diffraction (XRD) techniques. The catalyst was proven to be highly efficient for reduction of nitroarenes as well as Suzuki–Miyaura coupling reaction. The reduction of nitroarenes and Suzuki–Miyaura coupling reaction were performed in water medium and excellent yields of the products were achieved. The catalyst was easily recovered and recycled several times without any significant loss of catalytic activity.

Monodisperse CuPt alloy nanoparticles assembled on reduced graphene oxide as catalysts in the transfer hydrogenation of various functional organic groups

“…The yields of the reduced compounds were determined by 1 H NMR. All hydrogenated compounds are well‐known compounds in the literature and their characterization data were in a good agreement with literature …”

Role of the Support in Gold-Containing Nanoparticles as Heterogeneous Catalysts

“…However, 7% activity was lost over five reaction cycles, and the reaction rate deteriorated due to loss of catalyst. 335 A magnetic-core catalyst was also created by Li et al, who supported PdAu NPs on Fe 3 O 4 @MgAl-LDH core@shell materials. This material had smaller pores of 2.1−2.7 nm, and the PdAu NPs deposited were of 1.7−2.55 nm in size.…”

Palladium nanoparticles embedded in mesoporous carbons as efficient, green and reusable catalysts for mild hydrogenations of nitroarenes

“…Finally, changing the nature of the solvent was unsuccessful since low yields were observed in iPrOH or propane-1,2-diol and no reaction was observed in H 2 O (entries 9-11). It can be pointed out that, compared to numerous catalysts and reducing agents described, [15][16][17][18] both IM1 and IM2 allowed a chemospecic reduction of the nitro group (the acetyl remaining unchanged) and avoided the necessity of high H 2 pressure. Interestingly, performing the hydrogenation in the presence of a commercially available Pd/C or of Pd Encat NP30 catalyst afforded 1a in much lower yields (entries 12 and 13) conrming therefore the high activity of IM2.…”

“…13 In addition, from an environmental point of view, by reduction, these highly toxic and pollutant nitroarenes (oen obtained as by-products in synthesis or present as contaminants) are transformed in less hazardous aromatic primary amines of possible use. 14 Two major routes for the reduction of nitroarenes are generally used, either in the presence of sodium borohydride (NaBH 4 ) and a heterogeneous Ru-, 15 Au-, 16 Cu-(ref. 17) or Pd-catalyst (ref.…”