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Hydrogen complex

Di-hydrogen complexes such as (8.105) are believed to have been isolated [23a]. In other cases they may be formed as intermediates or exist in equilibrium (8.106) [Pg.628]

Although metal complexes with H ligands such as (8.105a) had been known for some time (e.g. (8.64) and (8.81) through (8.88), it was not nntil 1984 that the structure of the first di-hydrogen complex (8.105b) was characterised [24]. [Pg.629]

Structural isomerism can exist between mono and di hydrogen complexes as, for example, in Rh[P(CH2CH2PPh2)3H2] + (8.108). It is believed that there is less electron donation to the ligand [Pg.629]

Di-hydrogen complexes may be formed as intermediate species in reactions of H2 at metal centres. The H-H distance in such complexes is known to be somewhat longer than in molecular H2 thus indicating weaker linkages in the former. [Pg.629]

Dihydrogen complexes in some instances easily lose H atoms. [Pg.629]


The Chugaev elimination is of synthetic value, because it proceeds without rearrangement of the carbon skeleton. Other non-thermolytic elimination procedures often lead to rearranged products, when applied to the same substrates. However applicability of the Chugaev reaction is limited if the elimination is possible in more than one direction, and if a /3-carbon has more than one hydrogen. Complex mixtures of isomeric olefins may then be obtained. For example the thermolysis of xanthate 12, derived from 3-hexanol yields 28% S-hex-3-ene 13, 13% Z-hex-3-ene 14, 29% -hex-2-ene 15 and 13% Z-hex-2-ene 16 ... [Pg.54]

This is the first example of a proton transfer process to a hydride complex with a second-order dependence. Theoretical calculations indicate that the role of the HX molecules is the formation of W-H H-Cl- H-Cl adducts that convert into W-Cl, H2 and HCl2 in the rate-determining state through hydrogen complexes as transition states. [Pg.113]

Table 3 summarizes the scope and limitation of substrates for this hydrogenation. Complex 5 acts as a highly effective catalyst for functionalized olefins with unprotected amines (the order of activity tertiary > secondary primary), ethers, esters, fluorinated aryl groups, and others [27, 30]. However, in contrast to the reduction of a,p-unsaturated esters decomposition of 5 was observed when a,p-unsaturated ketones (e.g., trans-chalcone, trans-4-hexen-3-one, tra s-4-phenyl-3-buten-2-one, 2-cyclohexanone, carvone) were used (Fig. 3) [30],... [Pg.32]

The proposed mechanism of H2 evolution by a model of [FeFeJ-hydrogenases based upon DFT calculations [204-206] and a hybrid quanmm mechanical and molecular mechanical (QM/MM) investigation is summarized in Scheme 63 [207]. Complex I is converted into II by both protonation and reduction. Migration of the proton on the N atom to the Fe center in II produces the hydride complex III, and then protonation affords IV. In the next step, two pathways are conceivable. One is that the molecular hydrogen complex VI is synthesized by proton transfer and subsequent reduction (Path a). The other proposed by De Gioia, Ryde, and coworkers [207] is that the reduction of IV affords VI via the terminal hydride complex V (Path b). Dehydrogenation from VI regenerates I. [Pg.69]

Metal hydrides containing transition metal (TM)-hydrogen complexes, with the transition metal in a formally low oxidation state, are of fundamental interest for clarifying how an electron-rich metal atom can be stabilized without access to the conventional mechanism for relieving the electron density by back-donation to suitable ligand orbitals. By reacting electropositive alkali or alkaline earth metals ( -elements) with group 7, 8, 9, and 10 transition metals in... [Pg.645]

Kubas, G.J., R.R. Ryan, B.N. Swanson, P.J. Vergatini, J. Wasswerman, Molecular hydrogen complexes Coordination of a sigma bond to transition metals.. Am. Chem. Soc. 120,1988. [Pg.434]

Heating the B-doped samples above 200°C in vacuum to dissociate the hydrogenated complex results in flat spreading resistance (Rs) at the original bulk value. A second exposure to Hj restores the increased Rs at the surface. These are crucial experiments that demonstrate that hydrogen is involved and that the process is reversible and reproducible. [Pg.109]

In the first report of hydrogen neutralization of donor dopants in silicon, a novel bonding geometry was proposed for the donor-hydrogen complex... [Pg.139]

Fig. 6. Structural models for the donor-hydrogen complex in silicon (a) the antibonding Td site model and (b) the broken-bond Td site model (adapted from Zhang and Chadi, 1990a). Fig. 6. Structural models for the donor-hydrogen complex in silicon (a) the antibonding Td site model and (b) the broken-bond Td site model (adapted from Zhang and Chadi, 1990a).
Consider finally the equilibrium between molecular hydrogen complexes and the monatomic species. Although the existence of stable H complexes with n > 2 is by no means excluded—indeed, the platelets discussed in Chapter 7 seem to be such complexes with a very large n—we shall limit our discussion here to the case where only one kind of two-hydrogen complex, which we shall call a molecule and designate by H2, needs to be considered. We shall assume, in accordance with theoretical predictions (Van de Walle et al., 1988a,b Chang and Chadi, 1989 and earlier studies) that the stable state of H2 is neutral for all positions of the Fermi level in the gap there seems to be no experimental reason to doubt this.-In any case, equilibrium of the reaction... [Pg.252]

A convenient concept for introducing the surface boundary condition into the mathematical formulation of migration theory is that of what may be called a diffusional offset length d. Suppose that the external and surface conditions are describable by a set of parameters X, which we do not need to specify in detail we also allow the surface conditions to depend on the internal hydrogen concentration just beneath the surface. If the hydrogen complexes that are continually forming in the crystal are sufficiently immobile, the balance between inflow and outflow across the surface will depend only on X and on the concentration no(0) of H0 just beneath the surface. (If mobile H+ or H are present, the statement just... [Pg.284]


See other pages where Hydrogen complex is mentioned: [Pg.413]    [Pg.99]    [Pg.152]    [Pg.11]    [Pg.646]    [Pg.148]    [Pg.411]    [Pg.169]    [Pg.286]    [Pg.21]    [Pg.71]    [Pg.72]    [Pg.87]    [Pg.93]    [Pg.99]    [Pg.122]    [Pg.128]    [Pg.128]    [Pg.128]    [Pg.128]    [Pg.136]    [Pg.136]    [Pg.136]    [Pg.136]    [Pg.139]    [Pg.140]    [Pg.140]    [Pg.141]    [Pg.146]    [Pg.150]    [Pg.223]    [Pg.223]    [Pg.246]    [Pg.246]    [Pg.247]    [Pg.248]    [Pg.317]    [Pg.323]    [Pg.331]    [Pg.336]   
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See also in sourсe #XX -- [ Pg.397 ]

See also in sourсe #XX -- [ Pg.140 , Pg.141 ]

See also in sourсe #XX -- [ Pg.25 , Pg.191 , Pg.217 , Pg.237 , Pg.240 , Pg.242 , Pg.318 ]

See also in sourсe #XX -- [ Pg.2 , Pg.365 , Pg.367 , Pg.368 ]

See also in sourсe #XX -- [ Pg.53 ]




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Acetylene-hydrogen cyanide complex

Acid/pyridine complexation, hydrogen bonding

Actinide complexes hydrogen

Actinide complexes hydrogenation

Alkene complexes hydrogenation

Ammonia-water complex, hydrogen bonding

Aniline-ammonia complex, hydrogen bonds

Aniline-water complex, hydrogen bonds

Application to Hydrogen-Bonded Complexes

Argon-hydrogen chloride complexes

Association constants hydrogen-bonded complexes

Asymmetric Hydrogenation with Rhodium Complexes

Asymmetric hydrogenation DIOP complexes

Asymmetric hydrogenation catalysis with rhodium complexes

Asymmetric hydrogenation iridium complex

Asymmetric hydrogenation substrate complexes

Asymmetric hydrogenations over chiral metal complexes immobilized in SILCA

Binary Complexes of Hydrogen Fluoride and Water

Blue-shifted complexes, hydrogen bonds

Borane complexes carbon-hydrogen

Boron-hydrogen complex

Boron-hydrogen complex bond vibration

Boron-hydrogen complex models

Calcium-hydrogen chloride complexes

Carbene complexes with hydrogen halides

Carbenes hydrogen complexes

Carbon monoxide complex with hydrogen fluoride

Catalytic Activity of Cp Iridium Complexes in Hydrogen Transfer Reactions

Catalytic hydrogenation hydridopalladium complexes

Catalytic hydrogenation with chiral transition metal complexes

Catalytic hydrogenation, Ziegler-type complexes

Chiral metal complexes hydrogenation

Chromium complex hydrogenation

Cinnamic acid, a-acylaminoasymmetric hydrogenation rhodium complexes

Clay complexes Hydrogen bonding

Cobalt complex catalysts hydrogenation

Cobalt complexes asymmetric hydrogenation

Cobalt complexes carbonyl compound hydrogenation

Cobalt complexes hydrogenation

Cobalt complexes in hydrogen production from water

Complex hydrides hydrogen azide

Complex hydrides hydrogen halides

Complex hydrogen azide

Complex hydrogen halides

Complex hydrogenation catalyzed

Complex reactions. The hydrogen-bromine reaction

Complex with hydrogen

Complex-catalyzed Hydrogenation in Micellar Media

Complexation constants hydrogen-bond

Complexation, hydrogen bonding

Complexes Formed by Hydrogen Bonding

Complexes, catalytic hydrogenation

Complexes, catalytic hydrogenation ligand

Conjugated diene complexes hydrogenation

Conjugated diene complexes of hydrogen nucleophiles

Conjugated diene complexes of hydrogen sulphide

Copper complexes hydrogen ligands

Copper complexes hydrogenation

Correlations hydrogen complex stability

Dihydrido Iridium Triisopropylphosphine Complexes as Imine Hydrogenation Catalysts

Dinuclear complexes, hydrogen bonding

Diruthenium complex, hydrogen bonding

Electrolytic Fluorination of Heterocyclic Compounds in Trialkylamine Complexes with Anhydrous Hydrogen Fluoride

Enantioselective hydrogenation BINAP complexes

Enantioselective hydrogenation ruthenium complexes

Enantioselective hydrogenation titanium complexes

Ethane, rhodium complexes asymmetric hydrogenation

Ethylene complexes, hydrogen bonding

Ferric hydrogen peroxide complex

Five-coordinate platinum complexes hydrogen bonds

Force constants hydrogen complex stability

Formate complexes, hydrogen-bonded

High pressure, hydrogen complexes

Homogeneous hydrogenation rhodium complexes

Hydride complexes hydrogen bonding

Hydride complexes metal-hydrogen bond

Hydrido complexes Hydrogen bis

Hydrogen Bonding Interaction Used for Complexation to Rotaxane Structure

Hydrogen Bonding and Charge-Transfer Complexing

Hydrogen Motion in the B—H Complex

Hydrogen abstraction complexation

Hydrogen atom transfer from rhodium complexes

Hydrogen bond complex

Hydrogen bond mRNA-tRNA complex

Hydrogen bonded molecular complexes

Hydrogen bonded molecular complexes level

Hydrogen bonding ammonia complexes

Hydrogen bonding complex composition

Hydrogen bonding complex concentration

Hydrogen bonding complex dynamic mechanical property

Hydrogen bonding complex energy levels method

Hydrogen bonding complex, elongation

Hydrogen bonding computed complex formation energies

Hydrogen bonding iridium complex

Hydrogen bonding squaric acid complexes

Hydrogen bonding supramolecular complexes

Hydrogen bonding supramolecular copper complexes

Hydrogen bonding, 78 metal-dithiolene complexes

Hydrogen bonding—rotational complexes

Hydrogen bonds complex permittivity

Hydrogen bonds/bonding transition-metal complexes

Hydrogen chloride Complex with ammonia

Hydrogen chloride Complex with trimethylamine

Hydrogen complex formation with basic

Hydrogen complex formation with water

Hydrogen complex transition metal hydride

Hydrogen complexes between

Hydrogen complexes review

Hydrogen complexes stability

Hydrogen complexes, reactions

Hydrogen coordination complex catalysts

Hydrogen cyanide metal complexes

Hydrogen fluoride Complex with water molecule

Hydrogen fluoride complexes

Hydrogen fluoride pyridine complex

Hydrogen fluoride trialkylamine complex

Hydrogen fluoride triethylamine complex

Hydrogen hydride complexes

Hydrogen metal complexes

Hydrogen metal hydride complexes

Hydrogen molecular complex ions

Hydrogen molecular, reaction with ruthenium complexes

Hydrogen molecule, photoinduced complexes

Hydrogen nitrogenase complexes

Hydrogen nonclassical complexes

Hydrogen peroxide catalase complex

Hydrogen peroxide cobalt complexes

Hydrogen peroxide complexes

Hydrogen peroxide complexes, with

Hydrogen peroxide complexes, with catalase

Hydrogen peroxide titanium peroxo complex

Hydrogen peroxide vanadyl complexes

Hydrogen peroxide, addition platinum complexes

Hydrogen selenide metal complexes

Hydrogen storage complex hydride

Hydrogen sulfide metal complexes

Hydrogen sulfide, titanium complex

Hydrogen telluride metal complexes

Hydrogen transfer reactions catalyzed transition metal complexes

Hydrogen transition metal cluster complexes

Hydrogen, carbene complexes

Hydrogen, molybdenum complex

Hydrogen-Bonded Complexes with Polar Organic Compounds

Hydrogen-bond complexes anion recognition

Hydrogen-bond complexes poly derivatives

Hydrogen-bond complexes structure

Hydrogen-bonded complexes

Hydrogen-bonded complexes equilibrium geometries

Hydrogen-bonded molecules complex permittivity

Hydrogen-bonding association model complexes

Hydrogen-bonding complex, solid propertie

Hydrogen-bonding complexes

Hydrogen-palladium bonds hydridopalladium complexes

Hydrogen-palladium complexes

Hydrogenation Reactions Catalyzed by Transition Metal Complexes

Hydrogenation Using cationic complexes

Hydrogenation amino acid complexes

Hydrogenation carbon complex

Hydrogenation catalysts Arene chromium complexes

Hydrogenation chiral complexes

Hydrogenation complexes

Hydrogenation complexes

Hydrogenation hydride complex

Hydrogenation iridium complexes

Hydrogenation monohydrido complexes

Hydrogenation palladium carbene complexes

Hydrogenation platinum complexes

Hydrogenation platinum hydride complexes

Hydrogenation rhodium complexes

Hydrogenation rhodium-phosphine complexes

Hydrogenation transition metal complexes

Hydrogenation with rhodium complexes

Hydrogenation with ruthenium complexes

Hydrogen—Deep-Level-Defect Complexes in Silicon

Hydrogen—Shallow-Level-Defect Complexes in Compound Semiconductors

Hydrogen—Shallow-Level-Defect Complexes in Silicon

I 6 Hydrogen Bonds in Protein-Ligand Complexes

Imine complexes asymmetric hydrogenation

Imine complexes asymmetric transfer hydrogenation

Indium complexes hydrogen

Intramolecular hydrogen bond complex

Iridium complex catalyst, hydrogenation

Iridium complexes carbon-hydrogen activation reactions

Iridium complexes, in hydrogenation

Iridium hydrogen complexes

Iridium-Complex-Catalyzed Hydrogenations

Iron complex hydrogen

Iron complexes asymmetric hydrogenation

Iron complexes hydrogenation

Lanthanoid complexes hydrogenation

Lead complexes hydrogen bonding

Liquefaction complex, hydrogen

Lyotropic Hydrogen-Bonded Complexes

Manganese complexes formation with hydrogen peroxide

Metal complexes hydrogen bonding

Metal complexes, and hydrogenation

Metal-catalyzed hydrogenations organometallic complexes

Molecular hydrogen complexes

Molybdenum complexes hydrogen peroxide determination

Nickel complexes hydrogen cyanide reactions

Nickel complexes hydrogenation

Nickel-complex-catalyzed reactions hydrogenation

Olefin complexes hydrogenation (

Organocobalt complexes catalytic hydrogenation

Osmium complexes hydrogenation

Oxidation urea-hydrogen peroxide complex

Palladium complex catalysis hydrogenation

Palladium complexes alkyl, 3-hydrogen elimination

Palladium complexes hydrogenation

Pentachlorophenol, hydrogen-bond complexation

Peroxidase hydrogen peroxide complex

Phenol-Benzonitrile Hydrogen-bonded Complex

Phosphine, cyclohexyl methylrhodium complexes asymmetric hydrogenation

Phosphine, methyl-n-propylphenylrhodium complexes asymmetric hydrogenation

Phosphine, neomenthyldiphenylrhodium complexes asymmetric hydrogenation

Phosphine-metal complexes imine hydrogenation

Phosphine-metal complexes transfer hydrogenation

Phosphoric acid hydrogen-bonded complexes

Platinum complexes hydrogen-deuterium exchange

Plutonium complexes, hydrogen peroxide

Potential surfaces—complexes with intermolecular hydrogen

Propane, rhodium complexes asymmetric hydrogenation

Proton donors, hydrogen-bonded complexes

Rhodium , chiral “binap” complexes asymmetric hydrogenation with

Rhodium complex catalysts hydrogenation

Rhodium complexes Noyori catalytic asymmetric hydrogenation

Rhodium complexes asymmetric hydrogenation

Rhodium complexes carbon-hydrogen activation reactions

Rhodium complexes carbon-hydrogen bonds

Rhodium complexes hydrogen pressure

Rhodium complexes hydrogen-bonded acceptors

Rhodium complexes transfer hydrogenation

Rhodium-catalyzed hydrogenation Wilkinson complex

Ruthenium biimidazole complexes, hydrogen bonding

Ruthenium complex catalysts asymmetric hydrogenation

Ruthenium complex catalysts hydrogenation

Ruthenium complexes hydrogen

Ruthenium complexes hydrogenation

Ruthenium complexes transfer hydrogenation

Ruthenium complexes, Noyori catalytic asymmetric hydrogenation

Ruthenium-Complex-Catalyzed Hydrogenations

Self-Assembly of Closed Complexes by Hydrogen Bonding

Self-assembly, hydrogen bonded complexes

Shallow Level Complexes Containing Hydrogen

Silane, phenyltransfer hydrogenation molybdenum complex catalyst

Solute-hydrogen complexes

Solute-solvent hydrogen-bonded complexe

Squarate complexes hydrogen bonding

Stain, complexes hydrogenation with

Structure of Hydrogen-Bonded Complexes

Sulfido complexes hydrogen activation

Sulfoxide complexes activation of hydrogen

Sulfoxide complexes asymmetric hydrogenation

Sulfoxide complexes hydrogen transfer

Sulfoxide complexes hydrogenation

Sulfoxide complexes, catalytic hydrogenation

Supermolecules hydrogen-bond complexes

Supported transition metal complex catalysts hydrogenation

Supramolecular Construction of Chelating Bidentate Ligand Libraries through Hydrogen Bonding Concept and Applications in Homogeneous Metal Complex Catalysis

Tertiary phosphine-transition metal complexes hydrogenation, catalytic

Thallium complexes hydrogen

The Water-Hydrogen Fluoride Complex

Titanium complexes hydrogen peroxide determination

Titanium complexes hydrogen shift

Titanium complexes in hydrogen production from water

Titanocene complexes hydrogenation

Transfer hydrogenation chiral metal complexes

Transition metal complexes homogeneous hydrogenation

Transition metal complexes hydrogen activation

Transition metal complexes hydrogen-deuterium exchange

Transition metal complexes hydrogenation catalyzed

Transition metal complexes, olefin hydrogenation

Transition metal salts/complexes with hydrogen peroxide

Tungsten complexes hydrogen sulfide

Uranium complexes, hydrogen peroxide

Urea-hydrogen peroxide complex

Vanadium complexes hydrogenated

Vanadium complexes, hydrogen peroxide

Vanadium complexes, hydrogen peroxide determination

Water-soluble hydrogenation catalysts other than simple complex ions

Wilkinson complex, alkene hydrogenation

Xenon-hydrogen chloride complexes

Zirconium hydride complexes as hydrogenation catalyst

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