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Showing 1 to 20 of 28 for “"Hydrogenation reactions"”.
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Magnetic Resonance Studies of Three-Phase Heterogeneous Catalytic Hydrogenation Reactions
… (NMR) methods to study heterogeneously catalysed hydrogenation reactions, under continuous reaction conditions. The techniques developed aimed to elucidate the chemical composition inside the reactor and to provide a better understanding of the interactions of the reaction species with the …
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Studies of tartaric acid modified nickel supported catalysts for enantioselective hydrogenation reactions
… compound precursors, in the enantioselective hydrogenation of methyl acetoacetate to methyl 3‐hydroxybutyrate. Variables of reaction during modification such as pH and tartaric acid concentration, as well as Ni particle size above a minimum threshold of ca. 20 nm, proved not to have a major …
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Design and Modification of Half-Sandwich Ir(III), Rh(III), and Ru(II) Amino Acid Complexes for Application in Asymmetric Transfer Hydrogenation Reactions
… and their utility as asymmetric transfer hydrogenation catalysts of ketones. Variation of the metal center, the n-ring, and the aa was used to tune these systems for specific sets of ketones. Upon reaction with homochiral]s, the ligand environment in all of these complexes is …
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Modified ldh-supported au catalystssynthesis, characterization and catalytic performances in furfural liquid phase oxidation and hydrogenation
… a biomass-derived compound, via oxidation and hydrogenation reactions. Thus, for the mentioned transformations in the previous sentence, gold-modified LDH-based catalysts were prepared: MgAlZr-LDH for oxidation and NiAlZr- LDH for hydrogenation. Besides these studies, a photooxidation study of …
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Mesoporous Carbon/Silica Encapsulated Molybdenum and Ruthenium Nanocatalysts For Green Chemistry Applications
… catalysts for a wide range of catalytic reactions. This PhD project focuses on developing active, selective and stable nanocatalysts for green chemistry applications. In this work, molybdenum oxide and ruthenium nanoparticles were selected as model metal oxide and metal compounds to be …
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Structure Sensitivity in the Subnanometer Regime on Pt and Pd Supported Catalysts
… compared with nanoparticles for various reactions including hydrogenation reactions. However, the relationship between metal nuclearity, electronic and their unique catalytic properties are still unclear. Thus, it is crucial to establish their relations for better future catalyst design. …
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Mechanistic modeling of increased oxygen transport using functionalized magnetic fluids in bioreactors
… a liquid is of crucial importance to multiphase reactions because diffusion of a sparingly soluble gas across a gas-liquid interface generally limits the relevant reaction rates. Pertinent examples of multiphase reactions that have found application in the chemical and biochemical industries …
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Mechanochemistry: Redefining the Paradigm of Organic Chemistry
… has been employed for mechano-redox reactions using piezoelectric materials, photomechanochemistry and synthesis of organometallics. This research investigates different aspects of organic chemistry through mechanochemical perspective by unveiling the reactivity of Bertagnini’s salts …
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Structure sensitivity of H2/D2 Isotopic Exchange on Pt/Al2O3 catalysts
… catalysts are widely used industrially for hydrogenation reactions. However, the kinetics of hydrogen activation, a critical step for any hydrogenation reaction, is still not well understood on supported Pt surfaces. Recent studies had shown that activity and selectivity vary with Pt …
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Progress Toward The Total Synthesis Of The Natural Product Herbicide Ascaulitoxin Aglycone
… of inseparable diastereomers. Catalytic hydrogenation and transfer catalytic hydrogenation reactions using Pd catalysts were employed for the complete deprotection of three N-CBz and two carboxybenzyl groups towards target ascaulitoxin aglycone, but were met with limited success due to …
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Alkene hydrogenation on reduced nickel A-zeolite catalysts.
The individual and competitive hydrogenation reactions of ethene, propene and isobutene over various nickel metal-loaded 4A zeolites have been investigated. The reaction kinetics were found to be similar to those found by other workers for alkene hydrogenation over pure nickel metal. Reactions were …
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Multicomponent Cyclization Reactions: A General Approach To Dibenzocyclooctadiene Lignan Natural Product
… of related transformations, for example, the hydrogenation reactions, Mitsunobureactions, electrophilic additions to C-C double bonds and nucleophilic additions to carbonylgroups. The conformations of DBCODs containing C6 and/or C9 carbonyl groups are alsodiscussed based on experimental data. …
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The ultra-selective hydrogenation of Furfural on PtCu supported bimetallic nanoparticles and on Pt(111) under ultra-high vacuum
… catalysts and model single crystal surfaces. Hydrogenation reactions were carried out at pressures ranging from ultra-high vacuum to 20 bar. Temperature Programmed Desorption data in conjunction with Scanning Tunnelling Microscopy suggest that the decarbonylation of furfural on clean Pt(111) …
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Rigid Ruthenium PCcarbeneP Complexes for Small Molecule Activation, Hydrogenation, and Dehydrogenation
… ruthenium catalysts have had a huge role in hydrogenation reactions and are prominently studied as catalysts for hydrogen storage using small molecules like carbon dioxide. This thesis presents the synthesis and application of ruthenium-based PCcarbeneP complexes. The synthesis of dichlorido …
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Reductions by Cobalt-Catalyzed Production of Hydrogen Gas from NaBH4 in a Two-Chamber System
… system </em>for conducting catalytic hydrogenation reactions by obtaining hydrogen (H<sub>2</sub>) gas from stable sodium borohydride (NaBH<sub>4</sub>). Whereas NaBH<sub>4</sub> is widely used for a variety of reductions and is known to produce H<sub>2</sub> gas in protic media, to …
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Towards the rational design of nanoparticle catalysts
… catalysts towards a wide-range of hydrogenation reactions and the catalyst solution was reused for further catalytic reactions with minimal loss in activity. The synthesis of very pure and clean ILs has allowed a platform to study the effects of impurities in the imidazolium ILs on …
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Kinetic and mechanistic studies for the direct conversion of syngas to ethanol
… sites that might be different in nature. While hydrogenation reactions and C-O bond breaking were assigned to metallic Rh, CO insertion possibly occurs on dynamically formed non-metallic Rh species or clusters. A dynamic behavior of Rh metal particle surfaces is observed, which strongly depends …
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Tripodal Inorganic 2-Pyridyl-phosphine Ligands and Unsymmetrical Analogues: Towards New Applications in Catalysis
… are reported in Chapter 3. The stoichiometric reactions of (R2N)xP(2-py)3−x (R = Me, Et, x = 1, 2) with alcohols result in the formation of (alkoxy)-2-pyridyl-phosphines (RO)xP(2-py)3−x (R = Me, 2-Bu, Ph, x = 1, 2). This synthetic procedure also allows the introduction of enantiomerically pure …
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Inhibitor studies on para-aminobenzoic acid synthase.
… to give an amine using tin(II) chloride and hydrogenation reactions. Other forms of nitrogen protection using carbamates and bissilyl protection were also utilised. The formation of an enol pyruvyl group was accomplished in an original manner using lithium diisopropylamine to deprotonate a …
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