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Reductive Aromatization

One of the earliest means of introducing fluorine selectively into specific positions of aromatic compounds is the Balz-Schiemann reaction [77] which dates back to the 1920s. An isolated arene diazonium tetrafluoroborate is thermolyzed at up to 120 °C to yield the corresponding fluoroaromatic compound. Because of the infamously hazardous nature of isolated diazonium salts the scope of the classical variant of the Balz-Schiemann reaction was limited to the small scale. The high exothermicity of the reaction is most conveniently controlled by diluting the diazonium salt with a solid inert medium such as sea sand. In addition to the danger to the experimenter, the reproducibility of the reaction yield is quite poor. [Pg.45]


PtNi Reduction Aromatic nitro compound - Higher than mono-NP - [109]... [Pg.69]

Cyclization, reductive, aromatic nitro compounds to heterocyclic compounds, 48,115... [Pg.72]

On electrochemical or chemical reduction, aromatic phosphaallene derivatives yield anion-radicals. These species have two equivalent phosphorus nuclei. The unpaired electron oscillates between the two phosphorus atoms (Sidorenkova et al. 1998, Alberti et al. 1999) ArP=C( )-P( ) Ar o ArP( )-C(-)=PAr. [Pg.14]

Advantage has been taken of the propensity for equilibrium lithiation demonstrated for diethyl nicotinamide (447a) which has been induced under a double self-condensation to form the 2,7-diazaanthraquinone (452) (Scheme 136) (88S388). The quinone 452 was transformed by a reduction-aromatization sequence into the pyrido[3,4-g]isoquinoline (453) in high overall yield. [Pg.263]

The work of Jones and Lu has embraced a wide range of reactions including hydrogenations, borohydride reductions, aromatic dehalogenations, decarboxylations and hydrogen isotope exchange processes, (Scheme 9.3, Eqs. 1-3). In addition to the accelerated rates of reaction, new environmentally friendly routes have been developed, particularly solventless reactions that minimise waste production and facilitate containment107-110. [Pg.252]

Nitro Reduction. Aromatic amines are susceptible to reduction by both bacterial and mammalian nitroreductase systems. Convincing evidence has been presented that this reaction sequence is catalyzed by CYP. It is inhibited by oxygen, although NADPH is still consumed. Earlier workers had suggested a flavoprotein reductase was involved, and it is not clear if this is incorrect or if both mechanisms occur. It is true, however, that high concentration of FAD or FMN will catalyze the nonenzymatic reduction of nitro groups. [Pg.133]

Reductive aromatization of furanoglycal-substituted quinols give aryl C-glycals that are not stable. However, these compounds can be converted to aryl C-furanoglycosides by hydroboration (9). [Pg.97]

Reductions Aromatic nitro compounds, azo dyes, nitrosamines, A-oxides, sulfoxides Prostaglandin Synthetase (PGS) Cooxidation... [Pg.174]

Other functional groups may be present during reduction. Aromatic amino ethers are prepared by the same general procedures described above, e.g., 772-aminoanisole (80%) and 2-aminodiphenyl ether (94%). The reduction of o-nitrobenzaldehyde to the sensitive o-aminobenzaldehyde is successfully accomplished by the action of ferrous sulfate and ammonia (75%). m-Dimethylaminobenzaldehyde is formed by reduction of the nitro acetal in aqueous solution with sodium sulfide followed by methyla-tion (74% over-all) or by catalytic reduction of m-nitrobenzaldehyde in... [Pg.333]

Reduction. Aromatic nitro groups are reduced during hydrogenation using Ir/C as catalyst. Nitrate esters are retained. [Pg.203]

Reduction. Aromatic aldehydes can be effectively reduced to their corresponding alcohols by microorganisms. [Pg.339]

Perfluoroaromatic compounds can be obtained by reductive aromatization of readily accessible perfluorocycloaliphatic precursors [73]. Defluorination can be accomplished by contact with hot (500 °C) iron or iron oxide. After reducing the per-fluoroaliphatic compound the metal surface can be regenerated by passage of hydrogen gas. This method has been scaled up to a continuous flow process for industrial synthesis of a variety of perfluorinated aromatic compounds (Scheme 2.27). [Pg.43]

Light alkanes hydroisomerisation, Hydrocracking, Dewaxing, NOx reduction, Aromatic alkylation and transalkylation, Olefin oligomerisation... [Pg.7]

C-Aryl glycosides. Reductive aromatization of quinonc kctals by BH3 S(CH3)2 provides a new route to C-aryl glycosides. Thus 2-lithiodihydropyran (2) and 3 react to form a quinol kctal (4). Reaction of 4 with BH3 S(CH3)2 reduces the glycal double bond and provides the C-glycoside 5 derived from p-mcthylanisole. [Pg.50]


See other pages where Reductive Aromatization is mentioned: [Pg.355]    [Pg.29]    [Pg.29]    [Pg.112]    [Pg.113]    [Pg.97]    [Pg.72]    [Pg.5040]    [Pg.1202]    [Pg.253]    [Pg.5063]    [Pg.360]    [Pg.46]    [Pg.15]    [Pg.43]    [Pg.344]    [Pg.188]    [Pg.103]   


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Acid chlorides, aromatic, reduction

Alcohols aromatic, reductive cleavage

Aldehydes, aromatic reduction

Alkyl halides aromatic anion radical reduction

Amines, aromatic, reduction

Aromatic Amines and Other Reduction Products of Nitro Compounds

Aromatic Azo Reduction

Aromatic Birch reduction

Aromatic amines reductive dehalogenation

Aromatic carbonyl groups, reduction

Aromatic carboxylic Birch reduction

Aromatic compounds Birch reduction

Aromatic compounds Clemmensen reduction

Aromatic compounds Wolff-Kishner reduction

Aromatic compounds and aromaticity Birch reduction

Aromatic compounds dissolving-metal reduction

Aromatic compounds partial reduction

Aromatic compounds reduction

Aromatic compounds reductive silylations

Aromatic disulfides, reduction

Aromatic halides reduction

Aromatic halogen compounds reductive dehalogenation

Aromatic heterocycles, reduction

Aromatic hydrocarbons, electrochemical reduction

Aromatic hydrocarbons, reduction

Aromatic ketone reduction products

Aromatic nitro compounds reduction to hydroxylamines

Aromatic nitro compounds reduction with tin and hvdrochloric

Aromatic nitro group, reduction

Aromatic nitrocompounds, reduction

Aromatic reductive reactions

Aromatic selective reduction

Aromatic substitution Birch reduction

Aromatic, reduction

Aromatic, reduction

Aromatic, reduction with

Aromatics chemical reduction

Aromatics dissolving metal reduction

Azoxy compounds aromatic, reduction

Benkeser reduction aromatic rings

Biochemical reductions aromatic ketones

Birch reduction of aromatic

Birch reduction of aromatic compounds

Birch reduction of aromatic rings

Carbocyclic aromatics, reduction

Carbonyl compounds aromatic, reduction

Carboxylic acids aromatic, reduction

Carboxylic acids, aromatic, olefinic reduction

Cathodic Reduction of Aromatic and Heterocyclic Halogen Compounds

Cathodic Reduction of Aromatics

Clemmensen reduction aromatic aldehydes

Clemmensen reduction aromatic ketones

Condensed aromatics, reduction

Copper salts reduction, aromatic nitro compounds

Cyclization, reductive, aromatic nitro

Diazonium ions, aromatic reductive

Dinitro compounds, aromatic, partial reduction

Dissolving metal reduction, aromatic

Electrochemical reduction aromatic rings

Enantioselective reduction aromatic compounds

Halides reductive coupling with aromatic

Halo aromatics, reduction

Heterocycles, aromatic, halogen derivatives, reduction

Hydrogen sulfide reduction, aromatic nitro compounds

Isothiocyanates aromatic, reduction

Ketones aromatic, reduction

Ketones, aliphatic-aromatic reduction

Lithium-ammonia reduction aromatic rings

Nitro aldehydes, aromatic, reduction

Nitro aldehydes, aromatic, reduction preparation

Nitro compounds aromatic, reduction

Nitro compounds halogen-substituted aromatic, reduction

Nitro compounds, aromatic, reductive

Nitro compounds, aromatic, reductive cyclization with triethyl phosphite

Nitro-aromatic compounds reduction potential effect

Nitroso compounds aromatic, reduction

Organosilane Reduction of Aromatic Hydrocarbons

Oxidation and Reduction of Aromatic

Oxidation and Reduction of Aromatic Compounds

Partial reduction, of aromatic

Partial reduction, of aromatic compounds

Photochemical reduction aromatic rings

Polycycles, aromatic, reduction

Polycyclic aromatic hydrocarbons, reduction

Polynuclear aromatic hydrocarbons reduction

Radicals, reduction aromatic compounds

Radicals, reduction with aromatic compounds

Raney nickel alloy, reduction of aromatic nitriles to aldehydes

Reaction II.—Reduction under certain Conditions of Aromatic Ketones

Reduction aromatic amides

Reduction aromatic azides

Reduction aromatic rings

Reduction of Aromatic Aldehydes

Reduction of Aromatic Carboxylic Acids

Reduction of Aromatic Ketones

Reduction of Carbocyclic Aromatics

Reduction of Heterocyclic Aromatics

Reduction of Non-aromatic Heterocycles Containing the C N Function

Reduction of aromatic

Reduction of aromatic compounds

Reduction of aromatic compounds to dihydroaromatics by sodium and ammonia

Reduction of aromatic hydrocarbons

Reduction of aromatic nitriles

Reduction of aromatic nitro compound

Reduction of aromatic nitro groups

Reduction of aromatic rings

Reduction of aromatic systems

Reduction of aromatics

Reduction of the Aromatic Moiety

Reduction of the aromatic ring

Reduction reactions aromatic aniline methylation

Reduction reactions aromatic rings

Reductions of Heterocyclic N-Oxides and Aromatic Nitro Groups

Reductive cyclization of aromatic nitro

Reductive desulphuration of aromatic thioketones

Reductive elimination primary aromatic amines

Reductive of aromatic aldehydes

Reductive silylations aromatic rings

Rhodium-on-alumina, catalyzed reduction of aromatic nuclei

With calcium, reduction aromatic compounds

With lithium, reduction aromatic compounds

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