2979-24-0Relevant articles and documents
Microporous zirconia-silica mixed oxides made by sol-gel as catalysts for the liquid-phase oxidation of olefins with hydrogen peroxide
Palazzi, Chiara,Oliva, Liliana,Signoretto, Michela,Strukul, Giorgio
, p. 286 - 293 (2000)
Microporous zirconia-silica mixed oxides were prepared by sol-gel method and their reactivity in the oxidation of olefins with hydrogen peroxide was examined. The catalysts were characterized via BET methods, thermogravimetric analysis, XRD, UV-vis spectroscopy and TPD of ammonia. They had high surface areas, were amorphous and possessed only mild surface acidity. The reactivity order observed in the oxidation of olefins is a strong indication that the reaction proceeds through a heterolytic mechanism in which a nucleophilic olefin attacks a surface-electron-poor zirconium peroxo species. Although in all cases, the epoxide is likely involved as the primary reaction oxidation product. The acidity of the medium and/or support led to the opening of the oxirane ring. In the absence of solvent, the catalysts showed high selectivity (>99% glycol) at moderate temperature. In general, the activity and selectivity of the catalysts appear to be controlled by an appropriate polarity of the medium in which the reaction is carried out, by the polarity/acidity of the surface, and by the possibility to carry out the reaction at lower temperatures where the acidity effects of the hydrogen peroxide and silica matrix could be minimized.
Target-Architecture Engineering of a Novel Two-dimensional Metal-Organic Framework for High Catalytic Performance
Afshariazar, Farzaneh,Morsali, Ali
, p. 4239 - 4245 (2019)
A novel 2D-MOF, [Zn(L1)(oba)], an effective heterogeneous H-bond donor catalyst, based on carbohydrazide moiety (L1), was synthesized. Remarkable enhanced catalytic activity was achieved for methanolysis of epoxides by applying two effective strategies: (i) increasing the acidic strength of the H-bond donors and (ii) providing more accessible active sites within the framework.
Neighboring Methoxy Group Effect in Solvolysis Reactions of Cyclopentyl and Cyclohexyl p-Toluenesulfonates
Roberts, Donald D.
, p. 1857 - 1859 (1997)
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Pt and Ru Catalysts Based on Porous Aromatic Frameworks for Hydrogenation of Lignin Biofuel Components
Cherednichenko, K. A.,Kalinina, M. A.,Karakhanov, E. A.,Kulikov, L. A.,Makeeva, D. A.,Maximov, A. L.
, p. 711 - 720 (2021/08/03)
Abstract: A platinum catalyst and a ruthenium catalyst were synthesized from a porousaromatic framework, namely PAF-30. The catalyst properties were examined inhydrogenation of phenol and guaiacol at 80–250°C and at a hydrogen pressure of30 atm in the presence of various solvents. Significant effects of the reactionmedium, process conditions, and catalyst morphology on the reaction mechanismwere demonstrated. Reaction conditions optimal for complete conversion of phenoland guaiacol to hydrogenation products were selected for both catalysts. [Figure not available: see fulltext.]
Chemoselective and Tandem Reduction of Arenes Using a Metal–Organic Framework-Supported Single-Site Cobalt Catalyst
Akhtar, Naved,Begum, Wahida,Chauhan, Manav,Manna, Kuntal,Newar, Rajashree,Rawat, Manhar Singh
supporting information, (2022/01/19)
The development of heterogeneous, chemoselective, and tandem catalytic systems using abundant metals is vital for the sustainable synthesis of fine and commodity chemicals. We report a robust and recyclable single-site cobalt-hydride catalyst based on a porous aluminum metal–organic framework (DUT-5 MOF) for chemoselective hydrogenation of arenes. The DUT-5 node-supported cobalt(II) hydride (DUT-5-CoH) is a versatile solid catalyst for chemoselective hydrogenation of a range of nonpolar and polar arenes, including heteroarenes such as pyridines, quinolines, isoquinolines, indoles, and furans to afford cycloalkanes and saturated heterocycles in excellent yields. DUT-5-CoH exhibited excellent functional group tolerance and could be reusable at least five times without decreased activity. The same MOF-Co catalyst was also efficient for tandem hydrogenation–hydrodeoxygenation of aryl carbonyl compounds, including biomass-derived platform molecules such as furfural and hydroxymethylfurfural to cycloalkanes. In the case of hydrogenation of cumene, our spectroscopic, kinetic, and density functional theory (DFT) studies suggest the insertion of a trisubstituted alkene intermediate into the Co–H bond occurring in the turnover limiting step. Our work highlights the potential of MOF-supported single-site base–metal catalysts for sustainable and environment-friendly industrial production of chemicals and biofuels.
