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Oxide ring

Tertiary alcohols are usually degraded unselectively by strong oxidants. Anhydrous chromium trioxide leads to oxidative ring opening of tertiary cycloalkanols (L.F. Fieser, 1948). [Pg.136]

Benzene oxide and compounds derived from it are carcinogenic and can react with DNA to induce mutations This difference m the site of biological oxidation—ring versus side chain—seems to be responsible for the fact that benzene is carcinogenic but toluene is not... [Pg.444]

The reactions are highly exothermic. Under Uquid-phase conditions at about 200°C, the overall heat of reaction is —83.7 to —104.6 kJ/mol (—20 to —25 kcal/mol) ethylene oxide reacting (324). The opening of the oxide ring is considered to occur by an ionic mechanism with a nucleophilic attack on one of the epoxide carbon atoms (325). Both acidic and basic catalysts accelerate the reactions, as does elevated temperature. The reaction kinetics and product distribution have been studied by a number of workers (326,327). [Pg.415]

Oxidative Ring Closure Reactions 4.03.4.1.1 C—N bond formation N—N bond formation C—S bond formation N—S bond formation O—C bond formation O—N bond formation S—S, S—Se and Se—Se bond formation Electrophilic Ring Closures via Acylium Ions and Related Intermediates Ring Closures via Intramolecular Alkylations... [Pg.111]

Although some of the oxidative ring closures described above, e.g. reactions with lead tetraacetate (Section 4.03.4.1.2), may actually involve radical intermediates, little use has been made of this reaction type in the synthesis of five-membered rings with two or more heteroatoms. Radical intermediates involved in photochemical transformations are described in Section 4.03.9. Free radical substitutions are described in the various monograph chapters. [Pg.141]

Oxidative ring expansion occurs when the hydrazine (175) is treated with manganese dioxide (73TL4091). Diphenylcyclopropenone (176) reacts with ammonia and methylamine to give /3-lactams (69BCJ1777). Initial attack could occur at either C-1 or C-2 of the cyclopropenone. [Pg.262]

A variety of mono- and bi-cyclic /3-lactams have also been prepared by oxidative ring contraction of pyrrolidine-2,3-diones (180) (75JOC2356), and by the photolysis of pyrazolidin-3-ones (181) (78T1731, 75JOC3510, 75JOC3502, 75CC725). [Pg.262]

Benzoselenolo[2,3-ii]benzoselenophenes synthesis, 4, 116, 1078 Benzoselenolopyrylium cations oxidative ring contraction, 4, 969 [l]Benzoselenolo[3,4-ii][l,2,3]selenadiazoles synthesis, 6, 354 Benzo[h]selenophene, 2-acetyl-synthesis, 4, 966 Benzo[h]selenophene, 2-bromo-acylation, 4, 948... [Pg.553]

Benzo[6]thiophene, 4,7-dialkoxy-synthesis, 4, 930 Benzo[6]thiophene, 2,3-dialkyl-synthesis, 4, 877-878 Benzo[6]thiophene, 3 -(dialkylamino)-synthesis, 4, 925 Benzo[c]thiophene, 1,3-diaryl-oxidative ring opening, 4, 768 Benzo[6]thiophene, 2,3-dibromo-reactions, 4, 830... [Pg.560]

Benzo[c]thiophene, 1,3-diphenyl-oxidative ring opening, 4, 768 synthesis, 4, 141-142... [Pg.561]

The and -methylmorphimethines (formula, p. 251) are catalytically hydrogenated to hexahydro-derivatives by saturation of the two ethylenic linkages and opening of the oxide ring. The one from the e-form has m.p. 155° and that given by the -form, m.p. 174-5° (Speyer and Koulen ). [Pg.252]

A similar oxidative ring opening is reported to take place when 7-methoxy-l-styryl-j8-carboline is oxidized. The product, which was reported to be identical with harminic acid, is presumably the related compound 283 (R = CO2H or H). [Pg.152]


See other pages where Oxide ring is mentioned: [Pg.545]    [Pg.11]    [Pg.117]    [Pg.418]    [Pg.36]    [Pg.77]    [Pg.107]    [Pg.148]    [Pg.133]    [Pg.134]    [Pg.135]    [Pg.136]    [Pg.136]    [Pg.36]    [Pg.151]    [Pg.592]    [Pg.635]    [Pg.669]    [Pg.670]    [Pg.821]    [Pg.839]    [Pg.891]    [Pg.113]    [Pg.230]    [Pg.238]    [Pg.238]    [Pg.594]    [Pg.77]    [Pg.307]    [Pg.411]    [Pg.165]    [Pg.182]   
See also in sourсe #XX -- [ Pg.414 ]




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1.2.3.6- Tetrahydro-1,2,4-triazine 4-oxides ring-chain tautomerism

1.2.4- Triazine 4-oxides, ring contraction

2,3-butene oxide ring opening

5-Membered rings oxidation

5-Membered rings oxidative degradation

Achmatowicz oxidative ring expansion 500 -

Acid-Catalyzed Ring Opening of Ethylene Oxide

Allylic oxidation 12-membered ring

Allylic oxidation 14-membered ring structures

Application of the Oxo Reaction to Anhydro Sugars Having an Ethylene Oxide Ring

Aromatic Ring Oxidation to Quinones

Aromatic Ring Oxidation to Spirodienones

Aromatic compounds condensed, oxidative ring cleavage

Aromatic rings electrochemical oxidations

Aromatic rings oxidation

Aromatic rings oxidation with hydrogen peroxide

Aromatic rings oxidation with molecular oxygen

Aromatic rings oxidative cleavage

Aromatic rings photochemical oxidations

Aromatic rings stoichiometric oxidations

Aromatic rings, oxidation ipso substitution

Aromatic rings, oxidation isotope effects

Aromatic rings, oxidation mechanism

Aromatics oxidative ring cleavage

Benzene ring, oxidation potential

Benzotriazole 1-oxide ring

Boranes, aryldihydroxynitration and oxidation of the ring

Cephem 10-oxide ring

Chlorins, oxidative ring opening

Chromone ring oxidative

Covalent hydrates, oxidation ring-opening

Cycloalkanone oxidative ring

Cycloalkanone oxidative ring opening

Cyclobutane ring oxidative

Cyclohexanones oxidative ring opening

Cyclohexene oxidative ring contraction

Dihydro-, oxidation ring contraction

Ethers oxidative ring-formation

Ethylene oxide , ring-opening polymerization

Ethylene oxide ring opening

Ethylene oxide ring opening polymerisation

Ethylene-oxide ring

Ethylene-oxide ring formation

Five-membered rings nitrile oxide intramolecular cycloadditions

Four-membered titanium oxide ring

Four-membered titanium oxide ring intermediate

Furan ring opening, oxidative

Furan ring oxidative

Furan ring oxidative degradation

Heterocyclic ring oxidation

Imidazole 3-oxide ring

Imidazole 3-oxide ring benzimidazole 3-oxides

Imidazole 3-oxide ring from pyrimidines)

Isoquinoline ring oxidation

Molecular oxygen, oxidation ring opening

Nitrile oxides aldol” ring cleavage, intermediates

Nitrile oxides aminoalcohol ring cleavage

Nitrile oxides isoxazoline ring cleavage

Nitro ring closure, oxidative

Nucleophiles ring closure, oxidative

Oxidation and Reduction of Heterocyclic Rings

Oxidation aromatic ring systems

Oxidation benzene ring

Oxidation of Alkyl Substituents on the Aromatic Ring

Oxidation of aromatic rings

Oxidation of the Benzene Ring

Oxidation of the Ring

Oxidation of the aromatic ring

Oxidation photoinduced ring-opening

Oxidation-ring-opening process

Oxidative Cleavage of the Benzene Ring

Oxidative cleavage of aromatic rings

Oxidative cleavage of fused aromatic ring systems

Oxidative cleavage of fused heterocyclic ring systems

Oxidative cleavage with aromatic rings

Oxidative ring cleavage

Oxidative ring closure

Oxidative ring contractions

Oxidative ring expansion

Oxidative ring expansion of furans

Oxidative ring opening, amine

Oxidative ring-openings

Palladium-Catalyzed Indole Ring Synthesis Oxidative Cyclization

Penicillin S-oxide ring

Platinum-rhodium oxide, hydrogenation aromatic rings

Porphyrins oxidative ring-opening

Propylene oxide ring-opening

Pyran, dihydroallylic oxidation ring contraction

Pyrazine ring closure, oxidative

Pyridine 1-oxide ring expansion

Pyridine N-oxide ring

Pyridones, N-oxides and related compounds betainoid rings

Pyrrole ring oxidation

Pyrrole ring oxidative cleavage

Pyrrole ring, intramolecular oxidative

Quinazoline 3-oxide, 2-chloromethyl-, ring

Quinoline ring oxidation

Quinoxaline, benzene ring oxidation

Ring Opening Polymerization of Olefin Oxides

Ring contraction oxidation of fluorouracil

Ring contraction oxidation of phenols

Ring contraction reactions oxidative rearrangements

Ring electrodes oxidant concentration

Ring oxidative

Ring oxidative, preferential

Ring structures bromine oxidation

Ring-opening of cyclohexene oxide

Ring-opening of cyclopentene oxide

Ring-opening oxidation

Ring-opening polymerization polyethylene oxide

Ring-opening polymerization propylene oxide

Selective Oxidation of Aromatic Rings

Side chain oxidation rings

Stereoselective oxidative ring-contraction

Stilbene oxide epoxide ring opening

Stilbene oxide ring opening

Terpene oxides epoxide ring opening

Trimethylene oxide , ring-puckering

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