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Reduction carbonylation

Organoaluminum compounds such as triphenylaluminum (527) are used for ketone synthesis[387]. On the other hand, the reaction of /-BuiAl affords the corresponding alcohol 528 by reductive carbonylation[388]. [Pg.201]

Reductive carbonylation of nitro compounds is catalyzed by various Pd catalysts. Phenyl isocyanate (93) is produced by the PdCl2-catalyzed reductive carbonylation (deoxygenation) of nitrobenzene with CO, probably via nitrene formation. Extensive studies have been carried out to develop the phosgene-free commercial process for phenyl isocyanate production from nitroben-zene[76]. Effects of various additives such as phenanthroline have been stu-died[77-79]. The co-catalysts of montmorillonite-bipyridylpalladium acetate and Ru3(CO) 2 are used for the reductive carbonylation oLnitroarenes[80,81]. Extensive studies on the reaction in alcohol to form the A -phenylurethane 94 have also been carried out[82-87]. Reaction of nitrobenzene with CO in the presence of aniline affords diphenylurea (95)[88]. [Pg.538]

The Pd-catalyzed reductive carbonylation of methyl acetate with CO and H2 affords acetaldehyde. The net reaction is the formation of acetaldehyde from MeOH, CO, and H2P4]. Methyl formate (109) is converted into AcOH under CO pressure in the presence of Lil and Pd(OAc)2[95],... [Pg.540]

This process comprises passing synthesis gas over 5% rhodium on Si02 at 300°C and 2.0 MPa (20 atm). Principal coproducts are acetaldehyde, 24% acetic acid, 20% and ethanol, 16%. Although interest in new routes to acetaldehyde has fallen as a result of the reduced demand for this chemical, one possible new route to both acetaldehyde and ethanol is the reductive carbonylation of methanol (85). [Pg.53]

Attempts have been made to develop methods for the production of aromatic isocyanates without the use of phosgene. None of these processes is currently in commercial use. Processes based on the reaction of carbon monoxide with aromatic nitro compounds have been examined extensively (23,27,76). The reductive carbonylation of 2,4-dinitrotoluene [121 -14-2] to toluene 2,4-diaLkylcarbamates is reported to occur in high yield at reaction temperatures of 140—180°C under 6900 kPa (1000 psi) of carbon monoxide. The resultant carbamate product distribution is noted to be a strong function of the alcohol used. Mitsui-Toatsu and Arco have disclosed a two-step reductive carbonylation process based on a cost effective selenium catalyst (22,23). [Pg.454]

Because transition metals even in a finely-divided state do not readily combine with CO, various metal salts have been used to synthesize metal carbonyls. Metal salts almost always contain the metal in a higher oxidation state than the resulting carbonyl complex. Therefore, most metal carbonyls result from the reduction of the metal in the starting material. Such a process has been referred to as reductive carbonylation. Although detailed mechanistic studies ate lacking, the process probably proceeds through stepwise reduction of the metal with simultaneous coordination of CO (90). [Pg.67]

Scheme 33 Iron-catalyzed reductive carbonylation reported by Reppe [108]... Scheme 33 Iron-catalyzed reductive carbonylation reported by Reppe [108]...
Alkene-C=X (X=0, NR) Coupling (Reductive Carbonyl-Ene and Reductive Hydroacylation)... [Pg.105]

The first carbonyl complex of gold, [AuCl(CO)], was prepared in 192 52080,2081 and since then only a few more derivatives have been obtained. The [AuBr(CO)] derivative was prepared later and is unstable in the solid state.2082,2083 The reductive carbonylation of Au(S03F)3 in fluorosulfonic acid leads via [Au(CO)2]+ (solvent) to solid [Au(S03F)(C0)] (Scheme 30).2084 [Au(CO)2]+ salts are produced in strongly ionizing protic acids or in Lewis acids such as SbF5. [Pg.1026]

Pd/Al203-FeCl3, and Ce-Pd/Al203-FeCl3 catalysts exhibit activity for the synthesis of ethylphenylcarbamate from the reductive carbonylation of nitrobenzene with ethanol at 453 K and 2.07 - 2.93 MPa. The advantage of the use of Al203-supported Pd catalyst is the easy of catalyst recovery form the reactants/product mixture. [Pg.471]

The starting reactant is aniline for the oxidative carbonylation and nitrobenzene for the reductive carbonylation. The major advantage of the oxidative carbonylation is that the oxidative carbonylation is more thermodynamically favorable than the reductive carbonylation. The former can occur at a significantly milder condition than the latter (11-16). However, nitrobenzene is the feedstock for the production of aniline ... [Pg.472]

The reductive carbonylation has an advantage of low feedstock cost. A wide range of homogenous metal complexes have been tested for both reactions (1-16). The major drawback of the use of metal complex catalysts is the difficulty of catalyst recovery and purification of the reaction products (12). In addition, the gaseous reactants have to be dissolved in the alcohol/amine mixture in order to have an access to the catalyst. The reaction is limited by the solubility of the gaseous CO and 02 reactants in the liquid alcohol reactant (17). [Pg.472]

We have demonstrated that supported Pd and Cu catalysts are effective in catalyzing the oxidative carbonylation at low pressure reaction condition and the supported metal catalysts can be easily separated from the product mixture in both fixed bed and slurry phase reactors (12,17). The objective of this study is to investigate the feasibility of using Al203-supported Pd catalysts for catalyzing the reductive carbonylation of nitrobenzene with ethanol. [Pg.472]

Figure 1 Transmission IR spectra of reductive carbonylation over PdCl2(PPh3)2 at 2.93 MPa and 453 K. Figure 1 Transmission IR spectra of reductive carbonylation over PdCl2(PPh3)2 at 2.93 MPa and 453 K.
The results of TOF and carbamate yields are summarized in Table 1. Although PdCl2(PPh3)2 exhibited the highest activity, supported Pd exhibits good activity for the carbamate synthesis for the reductive carbonylation. [Pg.473]

Preparation/Formation of Cp2Ti(CO)2 via the Reductive Carbonylation of Cp2TiCl2/ (Cp2TiCl)2... [Pg.322]

In 1975 Demerseman and co-workers reported two new preparations for Cp2Ti(CO)2 via the reductive carbonylation of Cp2TiCl2. The first of these involved the reaction of either Cp2TiCl2 or (Cp2TiCl)2 with AlEt3 in a CO atmosphere. After these heptane suspensions or benzene solutions were stirred for 20 hours at 20°C, Cp2Ti(CO)2 (1) could be isolated in 30% yield (26). No speculation as to the mechanism of this reduction was discussed however, alkylation and CO insertion steps are probably involved. [Pg.323]

Like zirconium, the first fully characterized carbonyl complex of hafnium was reported in 1976 by Thomas and Brown (6). This complex, bis(i7-cyclopentadienyl)dicarbonylhafnium (3) was prepared via the reductive carbonylation of Cp2HfCl2 using sodium amalgam. While the reaction proceeded to give a moderate yield of 3 (30%), this corresponded to only 60 mg of isolated product. [Pg.336]

In a similar manner, Demerseman et al. attempted the high pressure reductive carbonylation of Cp2HfCl2 using lithium metal. However, after treatment of a THF solution with 200 atm of CO for 10 hours, no Cp2Hf(CO)2 (3) could be isolated (7). [Pg.336]


See other pages where Reduction carbonylation is mentioned: [Pg.53]    [Pg.448]    [Pg.178]    [Pg.181]    [Pg.183]    [Pg.929]    [Pg.1037]    [Pg.344]    [Pg.666]    [Pg.676]    [Pg.196]    [Pg.208]    [Pg.86]    [Pg.86]    [Pg.99]    [Pg.99]    [Pg.105]    [Pg.328]    [Pg.563]    [Pg.689]    [Pg.471]    [Pg.471]    [Pg.471]    [Pg.475]    [Pg.475]    [Pg.475]    [Pg.273]    [Pg.78]    [Pg.320]    [Pg.332]   
See also in sourсe #XX -- [ Pg.3 ]

See also in sourсe #XX -- [ Pg.3 ]




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1,2-diols reductive coupling of carbonyl compounds

Alcohols by reduction of carbonyl compounds

Alcohols by reduction of carbonyl compounds with

Alcohols by reduction of carbonyls

Alcohols carbonyl compounds reduction

Alcohols carbonyl reductions

Alcohols from Carbonyl Compounds Reduction

Alcohols from Reduction of Carbonyl Compounds

Alcohols from alcohol reductive carbonylation

Alcohols from ester reductive carbonylation

Alkali metals carbonyl compound reduction

Alkenes from carbonyl compounds by reductive

Alkenes reductive coupling with carbonyl compounds

Alkyne-carbonyl reductive couplings

Aluminum carbonyl compound reductions

Aluminum carbonyl reduction

Aluminum, triethylhydride donor reduction of carbonyls

Ammonium formate carbonyl compound reduction

Application of hydrides as reductants for coordinated carbonyl ligands

Aromatic carbonyl groups, reduction

Asymmetric Carbonyl Reductions

Asymmetric reduction of carbonyl compounds

Biochemical reduction unsaturated carbonyl compounds

Borane carbonyl compound reduction

Borane, carbonyl reduction

Boranes, trifluorodiethyl ether complex carbonyl compound reduction

By Alan Cox 2 Reduction of the Carbonyl Group

By Reduction of Carbonyl Compounds

Carbonyl Additions and Reductions

Carbonyl Chemistry Organometallic Reagents Oxidation and Reduction

Carbonyl Reduction with

Carbonyl and Imine Reductions

Carbonyl catalytic reductive coupling

Carbonyl compounds Clemmensen reduction

Carbonyl compounds Wolff-Kishner reduction

Carbonyl compounds acid chlorides, reduction

Carbonyl compounds aliphatic, reduction

Carbonyl compounds aromatic, reduction

Carbonyl compounds asymmetric reduction

Carbonyl compounds enantiomeric reductions

Carbonyl compounds esters, reduction

Carbonyl compounds heteroaromatic, reduction

Carbonyl compounds hydride reduction

Carbonyl compounds metal hydride reduction

Carbonyl compounds reduction

Carbonyl compounds reduction by sodium borohydride

Carbonyl compounds reduction to enolates

Carbonyl compounds reduction, asymmetric induction

Carbonyl compounds reductions, zinc-acetic acid

Carbonyl compounds reductive alkylation

Carbonyl compounds reductive amination

Carbonyl compounds reductive coupling

Carbonyl compounds reductive coupling reactions

Carbonyl compounds reductive coupling with activated alkenes

Carbonyl compounds reductive deoxygenation

Carbonyl compounds, a-halo reduction

Carbonyl compounds, a-halo reductive cleavage

Carbonyl compounds, from nitro reductive amination

Carbonyl compounds, reductive

Carbonyl compounds, reductive etherification

Carbonyl derivatives reductions

Carbonyl group oxidation and reduction

Carbonyl group reduction

Carbonyl group selective reduction

Carbonyl group, reduction resonance structures

Carbonyl groups hydride reduction

Carbonyl groups stereoselective reductions

Carbonyl nickel-catalyzed reductive allylation

Carbonyl reductases reductions

Carbonyl reduction

Carbonyl reduction

Carbonyl reduction 486 Subject

Carbonyl reduction Lewis basic functional groups

Carbonyl reduction by the Cannizzaro reaction

Carbonyl reduction chiral compound stereoselective synthesis

Carbonyl reduction diastereoselective

Carbonyl reduction fragmentation reactions

Carbonyl reduction mechanism

Carbonyl reduction of P-keto acetals

Carbonyl reduction proton donors

Carbonyl reduction under Meerwein-Ponndorf-Verley conditions

Carbonyl reduction using borohydrides

Carbonyl reduction using other methods

Carbonyl tosylhydrazone reductive deoxygenation

Carbonyl ylide reduction reaction

Carbonylation reductive, alcohols

Carbonylative reductive elimination

Catalysts carbonyl compound reduction

Catalysts reductive carbonylation

Catalytic reductive carbonylation

Catalytic reductive carbonylation nitrobenzenes

Chemoselective carbonyl group reduction

Conjugated carbonyl compounds, reduction with

Coupling reductive carbonyl

Cyclohexene carbonyl compound reduction

Deuterium labelling carbonyl reduction

Diastereoselective reduction of carbonyls

Dimethyl carbonate reductive carbonylation

Electrochemical reduction carbonyl compounds

Electrochemical reductive cleavage a-oxygenated carbonyl compounds

Electrophiles carbonyl compounds reduction

Enantioselective Carbonyl Reductions

Enantioselective Reduction of Carbonyl Compounds

Enantioselective reactions carbonyl reductions

Enantioselectivity reduction, of carbonyl compounds

Enzymatic Asymmetric Reduction of Carbonyl Compounds

Enzymic Asymmetric Carbonyl Reductions

Esters reductive carbonylation

Grignard reagents carbonyl reduction

High-nuclearity carbonyl clusters reduction reactions

Hydride Reduction of a Carbonyl Group

Hydride carbonyl reduction

Hydride donors reduction of carbonyls

Hydride reagents carbonyl compound reduction

Hydride reduction of carbonyl

Hydrocarbons from carbonyl compound reduction

Hydrogenation carbonyl compound reduction

Hydroxy carbonyls, reduction

Introduction to Carbonyl Chemistry Organometallic Reagents Oxidation and Reduction

Ionic carbonyl compound reduction

Iron carbonyl complexes reduction reactions

Iron carbonyls reductive cleavage

Labelling carbonyl reduction

Lactam carbonyl selective reduction

Lewis acids carbonyl compound reduction

Lewis bases carbonyl reductions

Limonene carbonyl compound reduction

Lithium aluminum hydride reduction, alcohols from, with carbonyl compounds

Lithium aluminum hydride, reduction carbonyls

Lithium carbonyl compound reduction

Metal carbonyls borohydride reduction

Metal carbonyls reduction

Metal carbonyls reductive carbonylation

Metal carbonyls reductive elimination

Metal groups carbonylates, reductive elimination reactions

Methyl esters, reductive carbonylation

Methyl ketals, reductive carbonylation

Nickel carbonyl, reduction

Nitro reductive carbonylation

Nitroarenes reductive carbonylation

One-Electron Reductions of Carbonyl Compounds and Esters Reductive Coupling

Organic carbonyl compounds, reductive

Organic carbonyl compounds, reductive amination

Osmium carbonyl clusters reduction

Oxidation and Reduction of Carbonyl Compounds

Oxidation-reduction reactions, carbonyl compounds

Palladium reductive carbonylation

Pre-Reduction of Carbonyl Groups with Lithium Aluminum Hydride

Preparation by Reduction of Carbonyl Compounds

Propylene reductive carbonylation

Reactions at the Carbonyl Group—Oxidation and Reduction

Reduction a-substituted carbonyl compounds

Reduction carbonyl methylenation step

Reduction carbonyl, borohydride

Reduction in carbonylation

Reduction of Aldehyde and Ketone Carbonyls

Reduction of Carbonyl Compounds to Alkenes

Reduction of Carbonyl Compounds to Hydrocarbons

Reduction of Carbonyl Compounds with Aluminum Alkoxides

Reduction of Carbonyl Derivatives

Reduction of Carbonyl and Other Functional Groups

Reduction of Functionalized Carbonyl and Dicarbonyl Compounds

Reduction of Labeled Prochiral Carbonyl Compounds and Oximes

Reduction of Main Group Oxides via Metal Carbonyls and Carbonylate Anions

Reduction of Metal Carbonyls with Alkali Metals and Sodium Tetrahydridoborate in Liquid Ammonia

Reduction of Other Carbonyl Compounds

Reduction of a, 3-unsaturated carbonyl

Reduction of a,/?-unsaturated carbonyl compounds

Reduction of a-Hydroxyimino Carbonyl Compounds

Reduction of activated carbonyl groups

Reduction of carbonyl and nitro functionalities

Reduction of carbonyl compounds

Reduction of carbonyl functionalities

Reduction of carbonyl functions

Reduction of carbonyl groups

Reduction of carbonyls

Reduction of o-B-unsaturated carbonyl compounds

Reduction of the carbonyl group

Reduction of unsaturated carbonyl compounds

Reduction reaction carbonyls

Reduction reactions carbonyl compounds

Reduction unsaturated carbonyl compounds

Reduction, azobenzenes carbonyl compounds

Reduction, induced carbonyl substitution

Reductions of Carbonyl Compounds to Alcohols

Reductions of metal carbonyls

Reductive Alkylation of Ammonia with Carbonyl Compounds

Reductive Alkylation of Primary Amines with Carbonyl Compounds

Reductive Carbonylation of Mixed Metal Complexes

Reductive Coupling of Carbonyl-Containing Compounds and Imines Using Reactive Manganese

Reductive Coupling of Carbonyls to Alkenes Adamantylideneadamantane

Reductive Deoxygenation of Carbonyl Groups

Reductive Deoxygenation of Carbonyl Groups to Methylene

Reductive N-Alkylation of Primary Amides with Carbonyl Compounds

Reductive amination of carbonyl compounds

Reductive amination of carbonyls

Reductive amination of fluoro-carbonyl compounds

Reductive carbonylation

Reductive carbonylation examples

Reductive carbonylation mechanism

Reductive carbonylation methanol

Reductive carbonylation methyl acetate

Reductive carbonylation thiocarbonylation reactions

Reductive carbonylations

Reductive coupling of carbonyl compounds

Reductive coupling of carbonyls to alkenes

Reductive coupling reactions carbonyl olefination

Reductive dimerization of carbonyl compounds

Reductive dimerization, of carbonyl

Reductive enzymes carbonyl reductases

Reductive of carbonyl compounds

Reductive reactions carbonyl reductases

Reductive reactions carbonylation

Regioselectivity carbonyl reduction

Selective reduction of carbonyl group in

Selectivity in the Reduction of Carbonyl Derivatives Containing a Chiral Carbon

Sodium borohydride carbonyl compound reduction

Sodium borohydride, reduction of carbonyl

Sodium borohydride, reduction of carbonyl compounds

Sodium carbonyl compound reduction

Sodium imide carbonyl reduction with

Solvation carbonyl reduction

Stereochemistry of carbonyl reduction

Stereoselective Carbonyl Reductions

Stereoselective reductions, of carbonyl

Stereoselective reductions, of carbonyl groups

Subject reductive carbonylation

Synthesis reductive carbonylation

Terminology for Reduction of Carbonyl Compounds

The Role of Proximal, Lewis Basic Functional Groups in Carbonyl Reduction

The Stereochemistry of Carbonyl Reduction

Topic 2.4. Polar Substituent Effects in Reduction of Carbonyl Compounds

Zinc, dialkylhydride donor reduction of carbonyls

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