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Hydrogenation activity

A white solid, m.p. 178 C. Primarily of interest as a brominaling agent which will replace activated hydrogen atoms in benzylic or allylic positions, and also those on a carbon atom a to a carbonyl group. Activating influences can produce nuclear substitution in a benzene ring and certain heterocyclic compounds also used in the oxidation of secondary alcohols to ketones. [Pg.69]

Other substances can activate hydrogen peroxide, for example, ferrous iron (p 352)- The products however are usually less well defined and different from those obtained when using peroxidase. [Pg.522]

The acetoacetic ester condensation (involving the acylation of an ester by an ester) is a special case of a more general reaction term the Claisen condensation. The latter is the condensation between a carboxylic ester and an ester (or ketone or nitrile) containing an a-hydrogen atom in the presence of a base (sodium, sodium alkoxide, sodamide, sodium triphenylmethide, etc.). If R—H is the compound containing the a- or active hydrogen atom, the Claisen condensation may be written ... [Pg.477]

The monosubstituted malonic ester still possesses an activated hydrogen atom in its CH group it can be converted into a sodio derivative (the anion is likewise mesomeric) and this caused to react with an alkyl halide to give a C-disubstituted malonic ester. The procedure may accordingly be employed for the synthesis of dialkyImalonic and dialkylacetic acids ... [Pg.484]

The mechanism of the reaction, which is of the aldol type, involves the car-bonyl group of tlie aldehyde and an active methylene group of the anhydride the function of the basic catalyst B (acetate ion 0H3000 or triethylamine N(0,Hb)j) is to form the anion of the active hydrogen component, i.e., by the extraction of a proton from the anhydride ... [Pg.707]

Anion exchange resins of the quaternary ammonium hydroxide type (e.g., De-Acidlte FF, IRA-400 or Dowex I) are strong bases and are useful cataly s for the cyanoethylatlon of alcohols and possibly of other active hydrogen compounds. [Pg.915]

A radically different course is followed when the reaction of 2-alkyl-substituted thiazoles is periormed in methanol or acetonitrile (335), 2 1 adducts containing seven-membered azepine rings (91) are being formed in which two of the original activated hydrogen atoms have altered positions (Scheme 55). A similar azepine adduct (92) was obtained by... [Pg.98]

Nickel catalysts although less expensive than rhodium and platinum are also less active Hydrogenation of arenes m the presence of nickel requires high temperatures (100-200°C) and pressures (100 atm)... [Pg.428]

This particular representation makes it easy to visualize formaldehyde as a step-growth monomer of functionality 2. Our principal interest is in the reactions of formaldehyde with the active hydrogens in phenol, urea, and melamine, compounds [II] [IV], respectively ... [Pg.323]

The hydrogen atoms shown in these monomers (only those underlined in phenol) are the active hydrogens, so these compounds have nominal functionalities of 3, 4, and 6, respectively. Note that a monosubstituted phenol would have a functionality of 2 and would be incapable of crosslinking. [Pg.324]

Compounds with active hydrogen add to the carbonyl group of acetone, often followed by the condensation of another molecule of the addend or loss of water. Hydrogen sulfide forms hexamethyl-l,3,5-trithiane probably through the transitory intermediate thioacetone which readily trimerizes. Hydrogen cyanide forms acetone cyanohydrin [75-86-5] (CH2)2C(OH)CN, which is further processed to methacrylates. Ammonia and hydrogen cyanide give (CH2)2C(NH2)CN [19355-69-2] ix.orn. 6<55i the widely used polymerization initiator, azobisisobutyronitrile [78-67-1] is made (4). [Pg.93]

This adds compounds with active hydrogen such as water, alcohols, and carboxyUc acids (63), to give l,4-dihydroxy-2-butanone or its derivatives. [Pg.106]

Further reaction of the active hydrogens on nitrogen in the urethane groups (3) can occur with additional isocyanate (1) at higher temperatures to cause formation of aHophanate stmctures. The active hydrogens in urea groups can also react with additional isocyanate to form disubstituted ureas which can stiU further react with isocyanate to form biurets (13). [Pg.405]

The use of polar solvents, such as /V, /V- dim ethyl fo rm am i de [68-12-2] is noted to result in extensive trimer formation. However, if the isocyanate is trapped using compounds such as alcohols, carboxyUc acids, and amines which contain active hydrogen, high yields are obtained (93). [Pg.456]

Developments in aliphatic isocyanates include the synthesis of polymeric aliphatic isocyanates and masked or blocked diisocyanates for appflcafions in which volatility or reactivity ate of concern. Polymeric aliphatic isocyanates ate made by copolymerizing methacrylic acid derivatives, such as 2-isocyanatoethyl methacrylate, and styrene [100-42-5] (100). Blocked isocyanates ate prepared via the reaction of the isocyanate with an active hydrogen compound, such as S-caprolactam, phenol [108-95-2] or acetone oxime. [Pg.459]

MEK is a colorless, stable, flammable Hquid possessing the characteristic acetone-type odor of low molecular weight aUphatic ketones. MEK undergoes typical reactions of carbonyl groups with activated hydrogen atoms on adjacent carbon atoms, and condenses with a variety of reagents. Condensation of MEK with formaldehyde produces methylisopropenyl ketone (3-methyl-3-buten-2-one) ... [Pg.488]

Phosphoms halides are subject to reactions with active hydrogen compounds and result in the elimination of hydrogen halide. They are convenient reagents in the synthesis of many esters, amides, and related compounds. However, because the involved hydrogen halide frequendy catalyzes side reactions, it is usually necessary to employ a hydrogen halide scavenger to remove the by-product. [Pg.362]

Starters. Nearly any compound having an active hydrogen can be used as starter (initiator) for the polymerization of PO. The common types are alcohols, amines, and thiols. Thus in Figure 2 ROH could be RNH2 or RSH. The fiinctionahty is derived from the starter, thus glycerol results in a triol. Some common starters are shown in Table 4. The term starter is preferred over the commonly used term initiator because the latter has a slightly different connotation in polymer chemistry. Table 5 Hsts some homopolymer and copolymer products from various starters. [Pg.351]

Formaldehyde may react with the active hydrogens on both the urea and amine groups and therefore the polymer is probably highly branched. The amount of formaldehyde (2—4 mol per 1 mol urea), the amount and kind of polyamine (10—15%), and resin concentration are variable and hundreds of patents have been issued throughout the world. Generally, the urea, formaldehyde, polyamine, and water react at 80—100°C. The reaction may be carried out in two steps with an initial methylolation at alkaline pH, followed by condensation to the desired degree at acidic pH, or the entire reaction may be carried out under acidic conditions (63). The product is generally a symp with 25—35% soHds and is stable for up to three months. [Pg.332]

Polymerization to Polyether Polyols. The addition polymerization of propylene oxide to form polyether polyols is very important commercially. Polyols are made by addition of epoxides to initiators, ie, compounds that contain an active hydrogen, such as alcohols or amines. The polymerization occurs with either anionic (base) or cationic (acidic) catalysis. The base catalysis is preferred commercially (25,27). [Pg.134]

Urethanes. The basis for urethane chemistry is the reaction of an isocyanate group with a component containing an active hydrogen. [Pg.311]

TMS triflate [27607-77-8] is an extremely powerful sdylating agent for most active hydrogens. It surpasses the sdylating potential of TMCS by a factor of nearly 10. It readily converts 1,2- and 1,3-diketones into disilylated dienes (7). [Pg.71]


See other pages where Hydrogenation activity is mentioned: [Pg.15]    [Pg.251]    [Pg.329]    [Pg.389]    [Pg.420]    [Pg.477]    [Pg.910]    [Pg.915]    [Pg.67]    [Pg.521]    [Pg.50]    [Pg.489]    [Pg.490]    [Pg.417]    [Pg.366]    [Pg.467]    [Pg.339]    [Pg.457]    [Pg.168]    [Pg.206]    [Pg.362]    [Pg.362]    [Pg.81]    [Pg.243]    [Pg.247]    [Pg.254]    [Pg.311]    [Pg.70]   
See also in sourсe #XX -- [ Pg.11 , Pg.30 ]

See also in sourсe #XX -- [ Pg.11 , Pg.30 ]




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A-Hydrogen, activation

Acetylene Active hydrogen

Activated alkenes, hydrogenation

Activated and hydrogen peroxide

Activated hydrogens in saturated carbonyl compounds

Activated hydrogens in unsaturated carbonyl compounds

Activated imine asymmetric hydrogenation

Activated imine direct asymmetric hydrogenation

Activated pyridines asymmetric hydrogenation

Activating Unactivated Carbon-Hydrogen Bonds

Activation energy ethylene hydrogenation

Activation energy hydrogen abstraction

Activation energy hydrogen termination

Activation energy of hydrogenation

Activation entropy hydrogenation

Activation hydrogen diffusion

Activation of Hydrogen Peroxide Using Inorganic and Organic Species

Activation of carbon-hydrogen bonds

Activation of hydrogen

Activation of hydrogen peroxide

Activation of molecular hydrogen

Activation of molecular hydrogen by homogenous

Activation of the Hydrogen Molecule

Activations hydrogen bond

Active Hydrogen-Reactive Chemical Reactions

Active Hydrogen-Reactive p-Aminobenzoyl Biocytin, Diazotized

Active Sites for HDS and Hydrogenation

Active carbon, hydrogen peroxide

Active carbon, hydrogen peroxide determination

Active hydrogen

Active hydrogen

Active hydrogen Mannich reaction

Active hydrogen activation

Active hydrogen compounds

Active hydrogen compounds acidity

Active hydrogen compounds acylation

Active hydrogen compounds alkylation

Active hydrogen compounds amination

Active hydrogen compounds aromatic nucleophilic substitution

Active hydrogen compounds arylation

Active hydrogen compounds base catalyst condensation

Active hydrogen compounds base-catalyzed

Active hydrogen compounds condensations

Active hydrogen compounds conversion

Active hydrogen compounds dimerization

Active hydrogen compounds formation

Active hydrogen compounds halogenation

Active hydrogen compounds ketones

Active hydrogen compounds nitration

Active hydrogen compounds nitrosation

Active hydrogen compounds reaction

Active hydrogen compounds reaction with aryl halides

Active hydrogen compounds with aldehydes

Active hydrogen compounds with arenes

Active hydrogen diazonium reaction

Active hydrogen reaction with nitrenes

Active hydrogen reactions

Active hydrogen with diazonium

Active hydrogen, definition

Active metal displacing hydrogen from water

Active oxygen hydrogen peroxide

Active sites hydrogenation

Active-Hydrogen-Mediated Hapten-Carrier Conjugation

Activity for hydrogenation of ethylene

Activity in hydrogenation

Activity of hydrogen ions

Acyl halides with active hydrogen

Acyl hydrogen bond activation

Addition of active hydrogen

Adsorption of hydrogen on activated carbons and carbon nanostructures

Alcohols active hydrogen determination

Aldehydes with active hydrogen

Alder carbon-hydrogen activation

Alkyl sulfates with active hydrogen

Alkyl sulfonates with active hydrogen

Amines active hydrogen determination

Amines from active hydrogen compounds

Anhydrides with active hydrogen

Arene derivatives carbon-hydrogen activation

Arenes with active hydrogen

Aromatics hydrogenation, active sites

Aryl halides with active hydrogen

Asymmetric Hydrogenation of Activated Imines

Asymmetric transfer hydrogenation activity

Biological Activation of Hydrogen

Biological systems, hydrogen activation

Brpnsted Acid Catalysis Hydrogen-Bonding Activation

C-Hydrogen, activation

C-Hydrogen, active

Carbon-hydrogen activation

Carbon-hydrogen activation hydrocarbons

Carbon-hydrogen bond activation

Carbon-hydrogen bond activation by

Carbon-hydrogen bond activation by Rh

Carbon-hydrogen bond activation energetics

Carbon-hydrogen bond activation flash photolysis

Carbon-hydrogen bond activation remote

Carbon-hydrogen bond activation theory

Carbon-hydrogen bond activation, aryls

Carbon-hydrogen bond cleavage, activation barrier

Catalyst, hydrogenation cooperative active sites

Catalysts activity in hydrogenation

Catalysts, hydrogenation active site

Catalysts, hydrogenation factors influencing activity

Catalytic Activity of Cp Iridium Complexes in Hydrogen Transfer Reactions

Catalytic activation of hydrogen

Catalytic activity of hydrogen

Catalytic hydrogenation activation energy

Cellulose hydrogen activation energy

Cinchona catalysts hydrogen-bonding activation

Cobalt, hydrogenation activation energy

Condensation with active hydrogen

Diastereoselective synthesis carbon-hydrogen bond activation

Enantioselective Conjugate Addition Reactions via Hydrogen-bonding Activation

Enantioselective hydrogenation of activated

Enolate anions from active hydrogen compounds

Epoxides with active hydrogen

Ethene, hydrogenation activation energy

From active hydrogen compounds

Functionalization carbon-hydrogen bond activation

Further Reactions of Active Hydrogen Compounds

Group VIII metals hydrogenation activities

Heterocycles from active hydrogen compounds

Heterogeneous Activation and Application of Hydrogen Peroxide

Heterolytic hydrogen activation

Homolytic hydrogen activation

Hydrides, Hydrogen Bonding and Dihydrogen Activation

Hydrocyanations hydrogen bonding activation

Hydroformylation reaction Hydrogen, homogeneous activation

Hydrogen PEFCs active

Hydrogen activated

Hydrogen activated

Hydrogen activating carbon monoxide

Hydrogen activating cobalt

Hydrogen activating copper

Hydrogen activating iridium

Hydrogen activating magnesium

Hydrogen activating molybdenum

Hydrogen activating nickel

Hydrogen activating niobium

Hydrogen activating palladium

Hydrogen activating rhenium

Hydrogen activating rhodium

Hydrogen activating ruthenium

Hydrogen activating tantalum

Hydrogen activating titanium

Hydrogen activating tungsten

Hydrogen activation

Hydrogen activation

Hydrogen activation Allochromatium vinosum

Hydrogen activation Clostridium pasteurianum

Hydrogen activation Desulfovibrio gigas

Hydrogen activation NiFe]-hydrogenase

Hydrogen activation Subject

Hydrogen activation competition between

Hydrogen activation electron paramagnetic resonance

Hydrogen activation energy

Hydrogen activation free-radical mechanism

Hydrogen activation heterolytic splitting

Hydrogen activation hydride oxidation

Hydrogen activation temperature dependence

Hydrogen activation, benzoin

Hydrogen activation, with immobilized

Hydrogen activation, with immobilized hydrogenase

Hydrogen activities, glass electrode

Hydrogen activities, lead oxides

Hydrogen activity

Hydrogen activity

Hydrogen activity series

Hydrogen adsorption activation energy

Hydrogen atom transfer activation energy

Hydrogen atoms, activated, substitution

Hydrogen autocatalytic activation

Hydrogen bonded amide activity

Hydrogen bonding nitroalkene acceptors activated

Hydrogen bonds proton path active site

Hydrogen chemically active, reasons

Hydrogen compounds, active reduction

Hydrogen cyanide activation barrier

Hydrogen diffusion activation energy

Hydrogen donors tools for the determination of POase activity in enzyme immunoassays

Hydrogen electrocatalytic activity

Hydrogen intramolecular heterolytic activation

Hydrogen ions active pumping

Hydrogen molecule activation

Hydrogen oxidation reaction kinetic activity

Hydrogen peroxide activation

Hydrogen peroxide antibacterial activity

Hydrogen peroxide decomposition active intermediates

Hydrogen peroxide scavenging activity

Hydrogen peroxide surface activation

Hydrogen phosphine-borane activation

Hydrogen reducing activity

Hydrogen spillover activated process

Hydrogen spillover catalytic activity

Hydrogen storage activated carbons

Hydrogen thioether activation

Hydrogen, activation potential

Hydrogen, catalytic activation

Hydrogen-bonding activation

Hydrogen-bonding activation Brpnsted acids

Hydrogen-bonding activation Diels-Alder reactions, dienes

Hydrogen-bonding activation Friedel-Crafts alkylations

Hydrogen-bonding activation aldehydes

Hydrogen-bonding activation carbonyl compounds, asymmetric

Hydrogen-bonding activation cascade reactions

Hydrogen-bonding activation cascades

Hydrogen-bonding activation compounds

Hydrogen-bonding activation enones

Hydrogen-bonding activation hydrogenation

Hydrogen-bonding activation nitroalkenes

Hydrogen-bonding activation nucleophiles

Hydrogen-bonding activation reactions

Hydrogen-bonding activation stabilized carbon

Hydrogen-bonding activation stereochemistry

Hydrogen-ion activities

Hydrogen-ion activity (pH) (cf. also Chapter

Hydrogen-ion activity in solution

Hydrogen-transfer reactions activation

Hydrogen-transfer reactions iminium activation

Hydrogenation active centers

Hydrogenation activities, hydrous titanium

Hydrogenation activity with

Hydrogenation dehydrogenation activity

Hydrogenation electrocatalytic activity

Hydrogenation mechanisms molecular hydrogen, activation

Hydrogenation of Aminoketones and Other Biologically Active Derivatives

Hydrogenation, activated

Hydrogenation, activated

Hydrogenation, catalyst activity

Iminium activation hydrogen-transfer

In Situ Activation of Cathodes for Hydrogen Evolution by Electrodeposition

Ir-Catalyzed Heterocyclization by C-H Bond Activation through Transfer Hydrogenation

Iridium complexes carbon-hydrogen activation reactions

Iridium hydrogenation activation energy

Ketimine/activated hydrogen

Ketone hydrogenation optically active alcohols

Kinetics hydrogen activation energy

Mechanism hydrogen activation

Metal clusters hydrogen activation

Metals with active hydrogen

Metals, activated hydrogen-metal exchange

Metals, activated hydrogenation

Methane, active hydrogen determination

Modes of hydrogen activation

Molecular hydrogen, activation

Molecular hydrogen, activation routes

Nitro compounds with active hydrogen

Noble metal catalysts hydrogen activation

Olefin hydrogenation hydrogen activation

Organosilicon compounds active hydrogen

Ortho esters with active hydrogen

Osmium hydrogenation activation energy

Oxidation reactions carbon-hydrogen activation

Oxidative rearrangements carbon-hydrogen bond activation

Oxygen carbon-hydrogen activation reactions

Palladium hydrogenation activation energy

Peroxisome proliferator-activated hydrogenation

Polyoxometalates hydrogen peroxide, activation

Preparation of polymethylphenylsiloxanes with active hydrogen atoms and vinyl groups at the silicon atom

Pressure dependence hydrogen activation

Quaternary ammonium with active hydrogen

Reaction with active hydrogen

Rhodium complexes carbon-hydrogen activation reactions

Silver oxide with active hydrogen

Some Recent Developments in Hydrogenation Activation of Hydrides by Transition Metal Derivatives

Sulfido complexes hydrogen activation

Sulfoxide complexes activation of hydrogen

THE ACTIVATION OF HYDROGEN

Thermochemical studies hydrogen activation

Thioethers with active hydrogen

Transfer hydrogenation active catalyst

Transfer hydrogenation active catalyst species

Transition metal catalysts carbon-hydrogen activation

Transition metal complexes hydrogen activation

U.S. hydrogen activities

Unsaturated aldehydes with active hydrogen

Unsaturated carboxylic esters with active hydrogen

Unsaturated ketones with active hydrogen

Working with Other Active Hydrogen Atoms

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