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Palladium oxides

Palladium catalysts have been prepared by fusion of palladium chloride in sodium nitrate to give palladium oxide by reduction of palladium salts by alkaline formaldehyde or sodium formate, by hydrazine and by the reduction of palladium salts with hydrogen.The metal has been prepared in the form of palladium black, and in colloidal form in water containing a protective material, as well as upon supports. The supports commonly used are asbestos, barium carbonate, ... [Pg.81]

The temperature rise in the inlet stage is limited by taking advantage of the unique properties of palladium combustion catalysts. Under combustion conditions, palladium can be either in the form of the oxide or the metal. Palladium oxide is a highly active combustion catalyst, whereas palladium metal is much less active. Palladium oxide is formed under oxidizing conditions... [Pg.405]

The hydrogenation of 5a-cholestanone (58) in methanolic hydrobromic acid over platinum gives 3j5-methoxycholestane ° (61). This compound is also obtained from the palladium oxide reduction of (58) in methanol in the absence of acid. Hydrogenation of 5 -cholestanone also gives the 3j5-methoxy product under these conditions. Reduced palladium oxides are quite effective for the conversion of ketones to ethers. The use of aqueous ethanol as the solvent reduces the yield of ether. Ketals are formed on attempted homogeneous hydrogenation of a 3-keto group in methanol. ... [Pg.136]

The oxidation kinetics of both gold and palladium alloys as a function of temperature and pressure have been reported by Opara et al and the behaviour of palladium and palladium oxide when heated in gaseous hydrochloride acid at 20-1000° by Ivashentsev and Ryumin . [Pg.945]

B. Sodium 2-aminobenzenesulfinate. 2-Nitrobenzenesulfinic acid (3.74 g., 0.020 mole) is suspended in 10 ml. of water, and sufficient 1AT NaOH (about 20 ml.) is added to the well-stirred mixture to dissolve the acid and bring the pH to 9. Palladium oxide (0.2-1.0 g., Note 9) is suspended in 20 ml. of water in a 200-ml. glass hydrogenation bottle. The bottle is attached to a hydrogenation apparatus such as that of Adams and Voorhees,2 and the suspension is shaken with hydrogen under a pressure of... [Pg.5]

The submitters used 0.2 g. of palladium oxide prepared by the method of Shriner and Adams 4 and required 2 hours for complete hydrogenation under a hydrogen pressure of 1 atm. The checkers used 1.0 g. of palladium oxide (75.7%) from... [Pg.7]

Palladium catalyst foe partial ee DUCTION OF ACETYLENES, 46, 89 Palladium on charcoal, catalyst for reductive methylation of ethyl p-mtrophenylacetate, 47, 69 in reduction of l butyl azidoacetate to glycine J-butyl ester 4B, 47 Palladium oxide as catalyst for reduction of sodium 2 nitrobenzene sulfinate, 47, S... [Pg.135]

It is usually difficult to discuss unambiguously on the role of the formation of sulphate, which may explain the deactivation. Their formation can equally occur on the support and on the noble metals. The poisoning effect of S02 has been reported by Qi el al. on Pd/Ti02/Al203 [112], However, in the presence of water, the stabilisation of hydroxyl groups could inhibit the adsorption of S02 [113], Burch also suggested a possible redispersion of palladium oxide promoted by the formation of hydroxyl species [114], Such tentative interpretations could correctly explain the tendencies that we observed irrespective to the nature of the supports, which indicate an improvement in the conversion of NO into N2 at high temperature. Nevertheless, the accentuation of those tendencies particularly on prereduced perovskite-based catalysts could be in connection with structural modifications associated with the reconstruction of the rhombohedral structure of... [Pg.316]

Electrophilic catalysis may play an important role in the case of the similar benzylic carbon, too. For an O-benzyl system, it was found in a 1997 experiment that palladium oxide is a much more effective catalyst than palladium metal when the catalyst has been prereduced with chemical reducing agents. This finding shows very clearly that the electrophilic character of the unreduced metal ions plays an important role in the hydrogenolysis of the benzyl C—O bonds. Additional support for this mechanism is the fact that a small amount of butylamine can inhibit the hydrogenolysis of the benzyl C—O bond. [Pg.122]

It was found in the case of O-benzyl systems that palladium oxide is much more effective than palladium metal. No such effect was observed with the N-benzyl system.8 It is possible that the N-compounds can poison the electrophile metal ions, and the hydrogenolysis of the N-benzyl bond can take place only by the hydrogenolytic cleavage instead of the insertion mechanism. This is supported by the experimental finding that the product amine can inhibit the catalyst, and this can be minimized by buffering at a pH less than 4. [Pg.161]

Wu, P., Xie, R., Imlay, J.A., and Shang, J.K. (2009) Visible-light-induced photocatalytic inactivation of bacteria by composite photocatalysts of palladium oxide and nitrogen-doped titanium oxide. Applied Catalysis B Environmental,... [Pg.130]

Supported palladium oxide is the most effective catalyst used in total methane oxidation and in catalytic oxidation of VOCs [1-5]. However, the activity of the conventional catalysts is not sufficient [5-6]. Recently, the Pd-zeolite catalysts have attracted considerable attention due to their high and stable CH4 conversion efficiency [4-8]. In this work, the effect of the preparation method, the nature of the charge-balancing cations, the palladium loading and the pre-treatment gas nature on the texture, structure and catalytic activity of the Pd-ZSM-5 solids are investigated. [Pg.409]

Mitra, P. Maiti, H. S. 2004. A wet-chemical process to form palladium oxide sensitiser layer on thin film zinc oxide based LPG sensor. Sens. Actuators B 97 49-58. [Pg.282]

A new pyrrole ring synthesis developed by Arcadi involves the addition of ammonia or benzylamine to 4-pentynones, the latter of which are conveniently prepared via a palladium oxidative coupling sequence as shown below for the synthesis of 40 [39,40]. [Pg.41]

Palladium catalysts, 10 42 14 49 16 250 Palladium-catalyzed carbonylation, 13 656 Palladium chloride/copper chloride, supported catalyst, 5 329 Palladium compounds, 19 650-654 synthesis of, 19 652 uses for, 19 653-654 Palladium films, 19 654 Palladium membranes, 15 813 Palladium monoxide, 19 651 Palladium oxide, 19 601... [Pg.669]

Variation of the nature of the gate electrode results in the different types of FET. For example, in the metal oxide semiconductor FET (MOS-FET) palladium/palladium oxide is used as the gate electrode. This catalyti-cally decomposes gases such as hydrogen sulphide or ammonia with the production of hydrogen ions, which pass into the semiconductor layer. An enzyme may be coated on the palladium, e.g. urease, which catalyses the production of ammonia from urea and thus provides a device for the measurement of this substrate. [Pg.194]

Oxide hydrosols synthesis relies on the destabilization of a true solution by a pH change. In order to prepare palladium oxide colloidal particles, two experimental routes can be carried out the neutralization of an acidic (basic) solution by an alkaline (acidic) solution, or thermohydrolysis of the palladium precursor solution. [Pg.258]

The formation of palladium oxide colloidal particles from an acidic palladium nitrate solution can be achieved by addition of an alkaline solution. The different steps, describing the chemistry involved in such a process are ... [Pg.258]

Using the multisite complexation model (MUSIC), ° the surface of palladium oxide has been modeled providing useful data on the nature, number, and the acid-base strength of the hydroxyl groups present on the different faces (111) and (10 0) of... [Pg.260]

Thermohydrolysis is another reaction which can be used to prepare colloidal suspensions of palladium oxide particles, and has been proven for other oxides. " ... [Pg.266]

In the following section, we describe the case of adsorption of a Sn complex onto a palladium oxide suspension. In an alkaline medium (a basic PdO hydrosol), chlorides in the SnCL complex are substituted in the coordination sphere of tin(IV) by hydroxo anions, which are in excess, yielding the stannate Sn(OH)g complex. The Sn Mossbauer spectroscopy spectrum of a bimetallic sol (frozen in liquid nitrogen) is compared with a true stannic solution. At the same tin concentration, it shows the changes in the Sn environment due to adsorption onto the PdO surface (Fig. 13.27). The isomer shift S is found to be close to zero for the stannate solution and increases when contacted with the PdO suspension, indicating a modification of the coordination sphere of tin. The increase in 5 can be correlated to an increase in the core level electronic density of tin. The quadrupole splitting A, is related to a modification of the symmetry of the close environment of tin, due to adsorption of Sn(OH)g complexes onto the PdO colloidal nanoparticles. [Pg.274]


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1,4-Dienes palladium-catalysed oxidation

Akiya Ogawa PALLADIUM-CATALYZED OXIDATION REACTIONS THAT HAVE NOT BEEN DISCUSSED IN EARLIER PARTS .l Background for Part VIII

Alcohols, oxidation aerobic, palladium-catalyzed

Aldehydes enolate oxidations, palladium®) acetate

Alkenes oxidations, palladium®) acetate

Alkenes oxidative 1,2-difunctionalization, palladium

Alkenes palladium-catalyzed oxidation

Allenes oxidations, palladium bromide

Aryl iodides, oxidative addition palladium complexes

Buchwald palladium -catalyzed oxidative

Carbazoles palladium -catalyzed oxidative

Carbon monoxide oxidation palladium oxide catalyst

Carbon-palladium bonds oxidation

Carbonate synthesis, alcohol oxidative carbonylations, palladium

Carbonyl compounds alcohol oxidations, palladium acetate

Carbonyl compounds aldehyde oxidations, palladium acetate

Carbonyl compounds oxidation, palladium catalysis

Catalyst palladium-zinc oxide

Catalyst palladous oxide—palladium black

Catalyst platinum/palladium partial oxidation

Catalysts, palladium monolithic oxidation

Catalytic oxidative cyclization using Palladium

Direct intramolecular oxidative functionalization, palladium-catalyzed

Electrochemical oxidation palladium catalysis

Enantioselective oxidations, palladium®) chloride

Enolates oxidations, palladium acetate

Ethylene palladium catalyzed oxidation

F Oxybismethane Palladium oxide

Formal oxidation state . palladium chemistry

Formic acid oxidation on Palladium

Heck reaction palladium acetate - oxidants

High-oxidation-state palladium complex

Intermolecular palladium -mediated oxidative couplings

Intramolecular oxidative functionalization, palladium-catalyzed

Investigation of Key Catalytic Intermediates in High-Oxidation-State Palladium Chemistry

Ketones alkene oxidations, palladium chloride

Ketones allylation-oxidations, 1,4-diketone synthesis, palladium

OXIDATION. ANODIC Palladium acetate

OXIDATION. ANODIC Palladium chloride

Olefin Oxidation with Palladium Catalyst

Olefins Wacker oxidations, bis palladium

Oxidants, palladium-catalyzed reactions, copper®) bromide

Oxidation of CO on Palladium

Oxidation of Methane on Supported Palladium Under Lean Conditions Kinetics, Structure and Properties

Oxidation palladium

Oxidation palladium

Oxidation palladium iodide

Oxidation palladium-catalysed

Oxidation palladium-oxo compounds

Oxidation reactions Palladium trifluoroacetate

Oxidation reactions palladium chemistry

Oxidation reactions palladium complexes

Oxidation reactions palladium synthesis

Oxidation states in a palladium-tin complex

Oxidation with palladium

Oxidation with palladium complexes

Oxidations bis palladium

Oxidations dichlorobis palladium

Oxidations palladium-catalyzed

Oxidations palladium®) bromide

Oxidations tetrakis palladium

Oxidative Addition to Palladium(O)

Oxidative addition palladium catalysis

Oxidative additions, palladium®) chloride

Oxidative alkenes, carboxylic acids, palladium chloride

Oxidative allenes, palladium®) bromide

Oxidative carbonylations palladium®) bromide

Oxidative carbonylations palladium®) chloride

Oxidative cleavage palladium acetate - oxidants

Oxidative coupling palladium catalysts

Oxidative coupling palladium pivalate

Oxidative coupling palladium-catalyzed

Oxidative coupling, palladium-catalysed

Oxidative functionalizations alkenes, palladium acetate

Oxidative palladium

Oxidative palladium pivalate

Oxidized palladium ions

Oxidizing agent Palladium

Oxidizing agents palladium compounds

Palladium , perchlorate oxidation

Palladium -catalyzed oxidation of olefins

Palladium -catalyzed oxidative

Palladium -catalyzed oxidative carbonylatio

Palladium -catalyzed oxidative cyclization

Palladium -ethylene oxidation

Palladium Catalysis for Oxidative 1,2-Difunctionalization of Alkenes

Palladium Phosphine oxides, nickel complexes with

Palladium Phosphorus oxide

Palladium Wacker oxidation

Palladium acetate allylic oxidation

Palladium acetate arylation/oxidation

Palladium acetate catalyst oxidation

Palladium acetate catalyst oxidative coupling with

Palladium acetate oxidants

Palladium acetate oxidation

Palladium alkene oxidation

Palladium alloys oxides

Palladium allylic oxidation

Palladium amine oxides

Palladium bis allylic oxidation

Palladium catalysis aerobic oxidation

Palladium catalysis arylation/oxidation

Palladium catalysis olefination, oxygen oxidant

Palladium catalysis oxidation

Palladium catalysis oxidation with

Palladium catalyst oxidation-reduction conversion

Palladium catalysts alcohol oxidation with

Palladium catalysts carbon monoxide oxidation

Palladium catalysts oxidative cyclization

Palladium catalyzed oxidation with

Palladium catalyzed oxidations aliphatics

Palladium catalyzed oxidations aromatics

Palladium catalyzed oxidations formation

Palladium catalyzed oxidations kinetic studies

Palladium catalyzed oxidations mechanism

Palladium catalyzed oxidations of cyclohexene

Palladium catalyzed oxidations of ethylene

Palladium catalyzed oxidations with added oxidant

Palladium chloride allylic oxidation

Palladium chloride, oxidation

Palladium complexes Baeyer-Villiger oxidation

Palladium complexes alkene oxidative reactions

Palladium complexes aryl halide oxidative addition

Palladium complexes hydrocarbon oxidation

Palladium complexes oxidation

Palladium complexes oxidation catalysts

Palladium complexes oxidation state

Palladium complexes oxidative addition

Palladium complexes oxidative carbonylation

Palladium complexes pyridine oxides

Palladium glucose oxidation

Palladium glycerol oxidation

Palladium mediated oxidation

Palladium methane oxidation

Palladium methyl acrylate oxidation

Palladium nickel oxide

Palladium olefin oxidation

Palladium oxidation state

Palladium oxidative addition

Palladium oxidative addition reactions

Palladium oxidative amidation

Palladium oxidative arylations

Palladium oxidative carbonylation

Palladium oxidative coupling

Palladium oxidative cross-coupling reactions

Palladium oxidative rearrangment

Palladium oxidative redispersion

Palladium oxide catalyst

Palladium oxide films

Palladium oxide fluorides

Palladium oxide on charcoal

Palladium oxide, crystal lattice

Palladium oxide-supported metal catalysts

Palladium oxidized

Palladium oxidized

Palladium propanediol oxidation

Palladium-Catalyzed Carbonylative Oxidation

Palladium-Catalyzed Carbonylative Oxidation of Arenes, Alkanes, and Other Hydrocarbons

Palladium-Catalyzed Indole Ring Synthesis Oxidative Cyclization

Palladium-Catalyzed Oxidation of Alkenes

Palladium-bathophenanthroline complex alcohol oxidation

Palladium-benzoquinone-based 1,4-oxidation

Palladium-catalysed oxidative diffusion

Palladium-catalysed reactions oxidation

Palladium-catalysed reactions oxidative addition

Palladium-catalyst oxidants

Palladium-catalyst oxidants copper®) acetate

Palladium-catalyst oxidants copper®) bromide

Palladium-catalyst oxidants copper®) chloride

Palladium-catalyzed Allylic Oxidations

Palladium-catalyzed Benzylic Oxidations

Palladium-catalyzed aerobic oxidation

Palladium-catalyzed amination oxidative addition

Palladium-catalyzed oxidative addition

Palladium-catalyzed oxidative cross-coupling

Palladium-catalyzed reactions oxidative addition

Palladium-mediated oxidative

Palladium-mediated oxidative coupling

Palladium-mediated oxidative cyclization

Palladium-mediated rearrangements oxidative rearrangement

Palladium®) complexes oxidation additions

Phenylacetylene, oxidative coupling palladium catalyst

Silyl enol ether palladium acetate oxidation

Silyl enol ethers Palladium oxidation

Steroids via palladium catalyzed oxidation

Styrene palladium-catalysed oxidation

Synthesis oxidation, palladium catalysis

Terminal Wacker oxidations, palladium®) chloride

Terminal alkenes oxidations, palladium®) acetate

Terminal oxidative carbonylations, palladium®) chloride

Thiazoles palladium-catalyzed oxidative

Wacker oxidation, palladium-catalyzed

Wacker oxidations palladium®) bromide

Wacker oxidations palladium®) chloride

Water alkene oxidations, palladium®) chloride

Yuzo Fujiwara and Chengguo Jia 2 Palladium-Catalyzed Carbonylative Oxidation Other than Those Involving Migratory Insertion

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