Masoud Kahrizi

New strategy by a two-component heterogeneous catalytic system composed of Pd–PVP–Fe and heteropoly acid as co-catalyst for Suzuki coupling reaction

We have developed a simple and efficient catalytic protocol composed of hollow palladium-poly(N-vinylpyrrolidone)-nano zero valent iron and H5PMo10V2O40 (Mo10V2) supported on Fe2O3@SiO2 core–shell nano particles, as reusable catalytic system for Suzuki coupling reaction under ligand- and base-free conditions. These reusable solid catalysts exhibited excellent activity and the methodology is applicable to diverse substrates providing good-to-excellent yields of desired products. This method has advantages of high yields, low reaction times, elimination of ligand and base, heterogeneous catalysts, and simple methodology. In order to study the role of Fe@Si–Mo10V2 in the Suzuki coupling reaction, electron transfer property of Fe@Si–Mo10V2 and Pd–PVP–Fe by means of cyclic voltammetry measurements were investigated. Moreover, this catalytic system could be recovered in a facile manner from the reaction mixture and recycled several times without any significant loss in activity. In this study, the heterogeneity of both component of our catalytic system was investigated and the content of palladium (Pd) and Mo10V2 into filtrates was evaluated quantitatively by inductively coupled plasma atomic emission spectroscopy (ICP-AES). According to the obtained results from the ICP-AES measurements, the small amount of Pd and Mo10V2 leach have been obtained.

Incorporation of palladium nanoparticles and 10-molybdovanado phosphoric acid in FeCo layered double hydroxide structure: electrochemical and catalytic investigation for Mizoroki–Heck coupling reactions

Palladium (Pd) has been immobilized on FeCo layered double hydroxide (LDH) intercalated 10-molybdovanado phosphate (FeCo/Mo10V2-Pd) for the first time. The structure was characterized using various characterization techniques. The electrocatalytic behavior of FeCo/Mo10V2-Pd was investigated using cyclic voltammetry and linear sweep voltammetry techniques. The presence of Mo10V2 enhanced the catalytic activity of FeCo-Pd in the Heck coupling reaction. Also, the collaboration of Pd and Mo10V2 with LDH as a mesoporous support was studied. These reusable solid catalysts exhibited excellent activity, and the methodology is applicable to diverse substrates providing good to excellent yields of the desired products. This method has advantages of high yields, low reaction times, elimination of ligand and base, heterogeneous catalysts and simple methodology. It is notable that FeCo/Mo10V2-Pd can easily separate from the reaction mixture using an external magnet and reused for at least four successive runs without any considerable decrease in its catalytic activity.

Collaboration of Ni, polyoxometalates and layered double hydroxides: synthesis, characterization, electrochemical and mechanism investigations as nano-catalyst in the Heck coupling reaction

Nickel (Ni) nanoparticles were immobilized on the surface of magnetic MgAl layered double hydroxide intercalated 10-molybdo-2-vanadophosphate (Fe–MgAl/Mo10V2–Ni) for the first time. The presence of Ni nanoparticles onthe high-surface area Fe–MgAl LDH structure in the presence of Mo10V2 makes this catalyst an ideal option in terms of efficiency and selectivity for Heck coupling reaction. Synergic effects of Mo10V2 and Ni were investigated by an electrochemical technique. Increasing of the ECSA of the catalyst compared to Fe–Mg–Al–Ni leads to enhancement of the catalytic activity and proves the synergic effect. A new catalytic mechanism was introduced for this kind of reaction. The resulting structure and its catalytic behavior were characterized by FT-IR, XRD, ICP-AES, TEM, SEM, EDX, EBSD, XPS, BET, VSM, CV, LSV and zeta potential analyses. More importantly, Fe–MgAl/Mo10V2–Ni can easily be separated from the reaction mixture using an external magnet and reused for at least four successive runs without any substantial reduction in its catalytic activity.