Magnetic Pd/Fe 3 O 4 /reduced-graphene oxide nanohybrid as an efficient and recoverable catalyst for Suzuki–Miyaura coupling reaction in water

A modified QuEChERS method based on a reduced graphene oxide-coated melamine sponge for multiresidue analysis of veterinary drugs in mutton by UPLC-MS/MS

The development of different matrix adsorbents is a research focus in the multiresidue analysis of veterinary drugs in foods. In this study, a novel elastic matrix adsorbent based on a reduced graphene oxide-coated melamine sponge was prepared and applied in matrix purification for the simultaneous determination of 52 veterinary drugs in mutton by UPLC-MS/MS. Efficient and convenient matrix removal was achieved through simple soaking and squeezing. Good linearities with determination coefficients ≥0.999 and low matrix effects ≤±13% were obtained in the range of 10-500 μg·kg-1. The obtained recoveries ranged from 63.7% to 109.5% at three spiked levels (10, 50, and 100 μg·kg-1), with relative standard deviations ≤8.1%. Low LODs and LOQs were obtained in ranges of 0.02-2.0 μg·kg-1 and 0.05-5.0 μg·kg-1, respectively. Based on the comprehensive results, our developed method showed good applicability in the analysis of multiresidues in various foods.

Palladium immobilized on guanidine functionalized magnetic nanoparticles: a highly effective and recoverable catalyst for ultrasound aided Suzuki–Miyaura cross-coupling reactions

The Fe3O4@SiO2-TCT-Gua-Pd catalyst anchored with guanidine moiety on Fe3O4 nanoparticles was synthesised for Suzuki–Miyaura cross coupling reaction.

Rapid one-pot synthesis of magnetically separable Fe3O4-Pd nanocatalysts: a highly reusable catalyst for the Suzuki-Miyaura coupling reaction

Heterogeneous catalysts comprising noble metals and magnetic materials allow a straightforward separation from a reaction using an external magnet and are recovered easily. In this study, we synthesized magnetic Fe₃O₄-Pd_n hybrid heterogeneous catalysts via a rapid one-pot aqueous-phase method. The synthesized Fe₃O₄-Pd NPs dispersed well with small size (∼50 nm), maintaining high magnetic responsiveness, and showed high reactivity and reusability for the Suzuki-Miyaura coupling reaction between aryl halides and phenylboronic acid. The synthesized Fe₃O₄-Pd₅₀ catalyst could be recycled at least ten times with no significant loss of catalytic activity by external magnet separation.

Design and synthesis of Fe3O4@SiO2@KIT-6@DTZ-Pd0 as a new and efficient mesoporous magnetic catalyst in carbon-carbon cross-coupling reactions

In this paper, a new type of mesoporous material based on KIT-6 has been introduced. In this aim, magnetic Fe3O4 nanoparticles and mesoporous silica KIT-6 have been combined to obtain mesoporous MNPs. The prepared magnetic mesoporous catalyst has been applied in different carbon-carbon cross-coupling reactions including Mizoroki-Heck, Suzuki-Miyaura, and Stille reactions. This magnetic mesoporous compound is characterized by various techniques including FT-IR, BET, VSM, SEM, XRD, and TGA.

A New ternary organometallic Pd(ii)/Fe(iii)/Ru(iii) self-assembly monolayer: the essential ensemble synergistic for improving catalytic activity

The synergistic catalytic effect in a hetero-trimetallic catalytic monolayer is one of the intriguing topics because the additive effects of the second or third component play an important role in improving the activity. In this paper, a new Schiff-base organometallic nanosheet containing Pd/Fe/Ru immobilized on graphene oxide (GO@H-Pd/Fe/Ru) was prepared and characterized. The catalytic performance of GO@H-Pd/Fe/Ru and synergistic effect were systematically investigated. GO@H-Pd/Fe/Ru was found to be an efficient catalyst with higher turnover frequency (TOF) (26 892 h-1) and stability with recyclability of at least 10 times in the Suzuki-Miyaura coupling reaction. The deactivation mechanism was caused by the aggregation of the active species, loss of the active species, the changes of the organometallic complex, and active sites covered by adsorbed elements during the catalytic process. GO@H-Pd/Fe/Ru was a heterogeneous catalyst, as confirmed by kinetic studies with in situ FT-IR, thermal filtration tests and poisoning tests. The real active center containing Pd, Ru and Fe arranged as Fe(iii)-Ru(iii)-Pd(ii)-Fe(iii) was proposed. Although Ru(iii) and Fe(iii) were shown to be less active or inactive, the addition of Fe and Ru could effectively improve the entire activity by their ''indirect'' function, in which Fe or Ru made Pd more negative and more stable. The ensemble synergistic effect between metals, the ligand and support was described as a process in which the electron was transferred from GOvia ligand to Ru, and then to Pd or from Fe to Pd to make Pd more negative, promoting the oxidation addition with aryl halide. Also, the vicinity of Ru around Pd as the promoter adsorbed aryl boronic acid, which facilitates its synergism to react with the oxidation intermediate to the trans-metallic intermediate.

A magnetic palladium nickel carbon nanocomposite as a heterogeneous catalyst for the synthesis of distyrylbenzene and biphenyl derivatives

Distyrylbenzene and 9,10-distyrylanthracene derivatives were synthesized using an Fe₃O₄@Pd@Ni/C nanocomposite as a recyclable catalyst. The catalyst was recycled up to eight times.

Selective hydrogenation of cinnamaldehyde over magnetic flower-like carbonaceous Pd catalysts

Novel magnetic flower-like carbonaceous Pd catalysts are constructed for the selective hydrogenation of the CC bond.

Recent Novel Hybrid Pd–Fe3O4 Nanoparticles as Catalysts for Various C–C Coupling Reactions

The use of nanostructure materials as heterogeneous catalysts in the synthesis of organic compounds have been receiving more attention in the rapid developing area of nanotechnology. In this review, we mainly focused on our own work on the synthesis of hybrid palladium–iron oxide nanoparticles. We discuss the synthesis of Pd–Fe3O4—both morphology-controlled synthesis of Pd–Fe3O4 and transition metal-loaded Pd–Fe3O4—as well as its application in various C–C coupling reactions. In the case of rose-like Pd–Fe3O4 hybrid nanoparticles, thermal decomposition can be used instead of oxidants or reductants, and morphology can be easily controlled. We have developed a method for the synthesis of nanoparticles that is facile and eco-friendly. The catalyst was recyclable for up to five continual cycles without significant loss of catalytic activity and may provide a great platform as a catalyst for other organic reactions in the near future.

Biochar-supported magnetic noble metallic nanoparticles for the fast recovery of excessive reductant during pollutant reduction

The catalytic reduction of diverse pollutants by noble metal catalysts in the presence of reductants is a highly effective and widely used method. However, the considerable cost of noble metal catalysts impedes the practical application of this method, and the recovery of excessive reductants has not been reported previously. In this work, we prepared inexpensive biochar-supported magnetic noble metallic nanoparticles (NPs) and efficiently recovered the excessive reductants in the form of H₂. The as-synthesized biochar-supported noble metallic NPs exhibited high H₂ recovery during the 4-nitrophenol reduction reaction. Results showed that the catalysts with low noble metallic content have higher H₂ recovery rate than commercial Pd/C, Ag/C, and Pt/C. The catalytic mechanism of magnetic biochar-supported noble metallic NPs was demonstrated to be a "synergetic effect", where biochar and Fe₃O₄ acted as accelerants that enable noble metallic NPs to produce active hydrogen for the reduction reaction, and the excess active hydrogen atoms combined to form H₂.

Synthesis and Characterization of Magnetic Zeolite Y-Palladium-Nickel Ferrite by Ultrasonic Irradiation and Investigating Its Catalytic Activity in Suzuki-Miyaura Cross-Coupling Reactions

Zeolite faujasite is widely used as a catalyst in many industrial catalytic applications. In this study, synthesis and characterization of magnetic zeolite Y-palladium-nickel ferrite were studied. First, palladium nanoparticles were combined with nickel ferrite and then placed on zeolite Y by ultrasonic treatment. The structure and morphology of the synthesized magnetic zeolite Y-palladium-nickel ferrite were characterized using Fourier transform infrared, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray, vibrating sample magnetometer, and inductively coupled plasma optical emission spectroscopy analysis. Also, we investigated the catalytic activity of this prepared zeolite in Suzuki-Miyaura coupling reaction between phenylboronic acid and aryl halides. Our study shows that magnetic zeolite Y-palladium-nickel ferrite is a suitable catalyst for Suzuki-Miyaura coupling reaction. Short reaction time, high yield, and easy reusability are the advantages of using this catalyst in carbon-carbon cross-coupling reactions.

A palladium complex immobilized onto a magnetic GO-MnFe2O4 surface as an effective and recyclable catalyst for the reduction of p-nitrophenol

A recyclable magnetic palladium complex catalyst immobilized onto a GO-MnFe₂O₄ surface was synthesized and characterized for the reduction of p-nitrophenol.

Synthesis of thiospinel CuCo2S4and CuCo2S4/reduced-graphene oxide nanohybrids as highly effective catalysts for the Sonogashira reaction

Thiospinel CuCo₂S₄and CuCo₂S₄/reduced-graphene oxide nanohybrids were first synthesized through a simple solvothermal approach. These nanohybrids were then used as non-phosphine catalysts for the Sonogashira reaction in water.

Efficient tandem aqueous room temperature oxidative amidations catalysed by supported Pd nanoparticles on graphene oxide

Pd nanoparticles deposited onto graphene oxide nanosheets (SE-GO/Pd_NPs) were found to successfully promote two oxidative processes for the synthesis of amides, providing alternative possibilities to these important compounds.