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Aromaticity aromatic heterocycles

The free-radical reactivity of thiazoles has been well studied with various radicals such as methyl, phenyl, substituted phenyl, cyclohexyl, and aromatic-heterocyclic, in nonpolar solvent or strong acids (180-182). [Pg.364]

Organic Analytes As noted earlier, organic compounds containing aromatic rings generally are fluorescent, but aromatic heterocycles are often phosphorescent. Many important biochemical, pharmaceutical, and environmental compounds are aromatic and, therefore, can be analyzed quantitatively by fluorometry... [Pg.429]

Because of the structural requirements of the bielectrophile, fully aromatized heterocycles are usually not readily available by this procedure. The dithiocarbamate (159) reacted with oxalyl chloride to give the substituted thiazolidine-4,5-dione (160) (see Chapter 4.19), and the same reagent reacted with iV-alkylbenzamidine (161) at 100-140 °C to give the 1 -alkyl-2-phenylimidazole-4,5-dione (162) (see Chapter 4.08). Iminochlorides of oxalic acid also react with iV,iV-disubstituted thioureas in this case the 2-dialkylaminothiazolidine-2,4-dione bis-imides are obtained. Thiobenzamide generally forms linear adducts, but 2-thiazolines will form under suitable conditions (70TL3781). Phenyliminooxalic acid dichloride, prepared from oxalic acid, phosphorus pentachloride and aniline in benzene, likewise yielded thiazolidine derivatives on reaction with thioureas (71KGS471). [Pg.129]

After the publication of a book on the prototropic tautomerism of aromatic heterocycles (76AHC(Sl)l) which covered the literature up to 1975, the study of the tautomerism of pyrazoles has not made great strides. In this section the main conclusions of this earlier review will be summarized and comments on a few recent and significant references added. [Pg.210]

Preparation and Reactions of Polyfluorinated Aromatic Heterocyclic Compounds Yakobson G G, Petrova, T D, Kobnna, L S Fluorine Chem Rev 7, 115-223 285... [Pg.12]

A surpnsing feature of the reactions of hexafluoroacetone, trifluoropyruvates, and their acyl imines is the C-hydroxyalkylation or C-amidoalkylaOon of activated aromatic hydrocarbons or heterocycles even in the presence of unprotected ammo or hydroxyl functions directly attached to the aromatic core Normally, aromatic amines first react reversibly to give N-alkylated products that rearrange thermally to yield C-alkylated products. With aromatic heterocycles, the reaction usually takes place at the site of the maximum n electron density [55] (equaUon 5). [Pg.843]

The preparation of enamines by reduction of aromatic heterocyclic bases and their quaternary salts or of lactams is not the most useful approach (97). The lithium aluminum hydride reduction of N-acyl enamines has been used with both fruitful and unsuccessful results. A series of 3-N-acetyl -d -cholestenes (104) has been prepared by desulfurization of the appropriate thiazolidine (105) (98,99). Lithium aluminum hydride reduction of the... [Pg.81]

PROTECTION FOR IMIDAZOLES, PYRROLES, INDOLES, AND OTHER AROMATIC HETEROCYCLES... [Pg.500]

The aromatic heterocycle phosphabenzene C5H5P (analogous to pyridine) was reported in 1971, some years after its triphenyl derivative 2,4,6-Ph3C5H2P. See also HP=CH2 29) nd [P(CN)2] ° (p. 484). The burgeoning field of heterocyclic phosphorus compounds featuring... [Pg.544]

In arriving at a picture of the influence of various substituents in aromatic heterocyclic compounds on quatemization, it is very difficult to separate the functions of electronic and steric effects. [Pg.11]

What are the details of the reaction mechanism for inorganic aromatic heterocycles While we are still arguing about aromatic substitutions, we wish to add this new challenge for future investigations. [Pg.359]

Organic chemistry is based on carbon, but nitrogen is fundamental to heterocyclic chemistry. Although there are many important aromatic heterocycles without nitrogen atoms (thiophene, furan, pyrylium salts, etc.), it is clear that the majority of heterocyclic systems contain nitrogen atoms. Thus, NMR spectroscopy ( " N NMR yields the same chemical shifts... [Pg.36]

Resonance energies and tautomerism of substituted aromatic heterocycles and their benzo derivatives Reaction-field-supermolecule approach to calculation of solvent effects... [Pg.87]

Derivatives of three of the four possible structural types of these aromatic heterocycles have been synthesized. [Pg.26]

In this chapter I have attempted to collect all the data available on the photoisomerization reactions of pentaatomic aromatic heterocycles. At the end of this work, I can note that all the results fit the hypothesis I reported in the introduction of this chapter. [Pg.83]

Eluorination of saturated and aromatic heterocycles with elemental fluorine 97MI30. [Pg.209]

Palladium(0)-catalyzed allylation of ambident nucleophilic aromatic heterocycles 96AHC(66)73. [Pg.210]

The reactions to be discussed may be represented by Eq. (1), where heterocyclic-H is an aromatic heterocyclic compound and R- is a free radical. The reaction is a substitution in that R replaces H, but... [Pg.131]

An analogous reaction is the Houben-Hoesch reaction,(sometimes called the Hoesch reaction) using nitriles 7 to give aryl ketones 8. This reaction also is catalyzed by Lewis acids often zinc chloride or aluminum chloride is used. The Houben-Hoesch reaction is limited to phenols—e.g. resorcinol 6—phenolic ethers and certain electron-rich aromatic heterocycles ... [Pg.134]

With respect to aromatic substrates, the Vilsmeier formylation reaction works well with electron-rich derivatives like phenols, aromatic amines and aromatic heterocycles like furans, pyrroles and indoles. However various alkenes are also formylated under Vilsmeier conditions. For example the substituted hexatriene 6 is converted to the terminal hexatrienyl aldehyde 7 in 70% yield ... [Pg.281]

Figure 15.8 Pyridine and pyrimidine are nitrogen-containing aromatic heterocycles with tt electron arrangements much like that of benzene. Both have a lone pair of electrons on nitrogen in an sp2 orbital in the plane of the ring. Figure 15.8 Pyridine and pyrimidine are nitrogen-containing aromatic heterocycles with tt electron arrangements much like that of benzene. Both have a lone pair of electrons on nitrogen in an sp2 orbital in the plane of the ring.
Indole is an aromatic heterocycle that has a benzene ring fused to a pyrrole ring. Draw an orbital picture of indole. [Pg.543]

Oxazole is a five-membered aromatic heterocycle. Would you expect oxazoie to be more basic or less basic than pyrrole Explain. [Pg.965]


See other pages where Aromaticity aromatic heterocycles is mentioned: [Pg.12]    [Pg.302]    [Pg.383]    [Pg.296]    [Pg.6]    [Pg.18]    [Pg.26]    [Pg.34]    [Pg.87]    [Pg.114]    [Pg.123]    [Pg.16]    [Pg.542]    [Pg.5]    [Pg.203]    [Pg.9]    [Pg.376]    [Pg.15]    [Pg.119]    [Pg.123]    [Pg.64]    [Pg.312]    [Pg.528]    [Pg.529]   
See also in sourсe #XX -- [ Pg.27 ]




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1,3-dipoles aromatic heterocycles

Addition to nitrogen heterocyclic aromatic compounds

Additions of Allyl- and Benzyltrimethylsilanes to Aromatic Heterocyclic N-Oxides

Amination of Aromatic Heterocyclic Lactam Systems

Aromatic Compounds, definition heterocyclic

Aromatic Five-Membered Ring Heterocyclics

Aromatic Heterocycles Pyridine and Pyrrole

Aromatic and Heterocyclic Compounds

Aromatic and Heterocyclic Ligands

Aromatic and heterocyclic amines

Aromatic and heterocyclic double bonds

Aromatic boron heterocycles

Aromatic compounds and aromaticity heterocyclic

Aromatic compounds heterocycles

Aromatic compounds heterocyclic spectra

Aromatic heterocycle synthesis benzimidazoles

Aromatic heterocycle synthesis indoles

Aromatic heterocycle synthesis pyridazines

Aromatic heterocycle synthesis pyridines

Aromatic heterocycle synthesis pyridones

Aromatic heterocycle synthesis quinolines

Aromatic heterocycles defined

Aromatic heterocycles electron-deficient

Aromatic heterocycles electron-excessive

Aromatic heterocycles five-membered

Aromatic heterocycles nitrations, nitric acid

Aromatic heterocycles pyridine

Aromatic heterocycles, Buchwald-Hartwig

Aromatic heterocycles, reduction

Aromatic heterocyclic amines physical properties

Aromatic heterocyclic compounds, solid-phase

Aromatic heterocyclic containing

Aromatic heterocyclic imide system

Aromatic heterocyclic nitrogen compounds

Aromatic heterocyclics - production and uses

Aromatic heterocyclics, and

Aromatic hydrocarbons and heterocycles photocycloaddition

Aromatic nitrogen heterocycles

Aromatic nitrogen heterocycles oxygen nucleophiles

Aromatic phosphorus heterocycles

Aromatic phosphorus heterocycles review

Aromatic six-membered nitrogen heterocycles

Aromatic six-membered nitrogen heterocycles regioselective substitution

Aromatic-heterocyclic polymers

Aromatic-heterocyclic polymers characterization

Aromatic-heterocyclic polymers processing

Aromatic-heterocyclic polymers solubility

Aromaticities of heterocycles

Aromaticities of heterocycles and

Aromaticity and heterocycles

Aromaticity concept of in heterocyclic chemistry

Aromaticity heterocyclic aromatic compounds

Aromaticity heterocyclics

Aromaticity heterocyclics

Aromaticity nitrogen heterocycles

Aromaticity of heterocycles

Aromaticity of heterocyclic compounds

Aromaticity of heterocyclic rings

Aromaticity of heterocyclics

Aromaticity oxygen heterocycles

Aromaticity, of five-membered heterocycles

Aromatics and Heterocyclics

Aromatics arenes, heterocycles

Aromatics, n-heterocyclic

Aromatization N-heterocyclics

Aromatization of N-heterocyclics

Benzo-fused five-membered heterocycles aromaticity

Black Sheep of the Family Heterocyclic Aromatic Compounds

Carcinogens heterocyclic aromatic amines

Cathodic Reduction of Aromatic and Heterocyclic Halogen Compounds

Chemical shifts of selected heterocyclic and polycyclic aromatic

Concept of aromaticity in heterocyclic

Cyclizations to 5-Membered Aromatic Heterocycles

Derivatives of Aromatic Heterocyclic Compounds

Diels-Alder reaction with aromatic heterocycles

Eight-membered heterocycles, aromaticity

Electron-poor aromatic heterocycles

Electron-rich aromatic heterocycles

Fish, heterocyclic aromatic amines

Five-Membered Aromatic Heterocycles with One Heteroatom

Five-membered heterocycles aromaticity

Five-membered ring heterocycles, relative aromaticity

Four-membered heterocycles aromaticity

Grignard reagents addition heterocyclic aromatic

Group 2 - Aromatic and Heterocyclic Protons

HETEROCYCLES FUSED TO TWO AROMATIC RINGS

Heterobenzenes and Other Heterocyclic Aromatic Compounds

Heterocycle synthesis aromatic

Heterocycles aromatic

Heterocycles aromatic

Heterocycles aromatic polyesters

Heterocycles aromatic with 2 heteroatoms

Heterocycles aromatic, 5-ring

Heterocycles aromatic, reactions

Heterocycles aromaticity

Heterocycles aromatization

Heterocycles aromatization

Heterocycles from aromatic compounds

Heterocycles nucleophilic aromatic

Heterocycles relative aromaticity

Heterocycles, acylation electrophilic aromatic

Heterocycles, aromatic Quinoline

Heterocycles, aromatic, halogen derivatives, reduction

Heterocycles, aromatic, nickel

Heterocyclic Aromatic Compounds and Huckels Rule

Heterocyclic Aromatic Systems

Heterocyclic aromatic

Heterocyclic aromatic amine bases

Heterocyclic aromatic amines

Heterocyclic aromatic amines (HAAs

Heterocyclic aromatic amines Subject

Heterocyclic aromatic amines analysis

Heterocyclic aromatic amines basicity

Heterocyclic aromatic amines bromination

Heterocyclic aromatic amines electrochemical detection

Heterocyclic aromatic amines electrophoresis

Heterocyclic aromatic amines liquid chromatography

Heterocyclic aromatic amines mass spectrometry

Heterocyclic aromatic compounds activating electrophilic functional

Heterocyclic aromatic compounds description

Heterocyclic aromatic compounds fused

Heterocyclic aromatic compounds groups

Heterocyclic aromatic compounds nitrogen atom

Heterocyclic aromatic compounds pyridine resembles benzene

Heterocyclic aromatic compounds pyrrole

Heterocyclic aromatic compounds thiophene

Heterocyclic aromatic compounds valence electrons

Heterocyclic aromatic fiber

Heterocyclic aromatic nitrogen

Heterocyclic aromatic rings

Heterocyclic aromatic species

Heterocyclic aromatic substrates

Heterocyclic aromatic systems, lithiation

Heterocyclic aromaticity, concept

Heterocyclic aromatics

Heterocyclic aromatics

Heterocyclic compounds Cyclic organic aromatic

Heterocyclic compounds aromatic

Heterocyclic compounds aromatic heterocycles

Heterocyclic compounds electrophilic aromatic

Heterocyclic compounds electrophilic aromatic substitution

Heterocyclic compounds nucleophilic aromatic

Heterocyclic compounds nucleophilic aromatic substitution

Heterocyclic compounds, aromatic benzimidazoles

Heterocyclic compounds, aromatic benzofurans

Heterocyclic compounds, aromatic benzoxazoles

Heterocyclic compounds, aromatic coumarins

Heterocyclic compounds, aromatic dihydropyridines

Heterocyclic compounds, aromatic furans

Heterocyclic compounds, aromatic imidazoles

Heterocyclic compounds, aromatic indoles

Heterocyclic compounds, aromatic indolizines

Heterocyclic compounds, aromatic isoxazoles

Heterocyclic compounds, aromatic oxadiazoles

Heterocyclic compounds, aromatic oxazoles

Heterocyclic compounds, aromatic purines

Heterocyclic compounds, aromatic pyrazoles

Heterocyclic compounds, aromatic pyridines

Heterocyclic compounds, aromatic pyrimidines

Heterocyclic compounds, aromatic pyrroles

Heterocyclic compounds, aromatic quinazolines

Heterocyclic compounds, aromatic quinolines

Heterocyclic compounds, aromatic tetrazines

Heterocyclic compounds, aromatic tetrazoles

Heterocyclic compounds, aromatic thiadiazoles

Heterocyclic compounds, aromatic thiazoles

Heterocyclic compounds, aromatic thiophenes

Heterocyclic compounds, aromatic triazines

Heterocyclic compounds, aromatic triazoles

Heterocyclization and Aromatization

High performance fibers heterocyclic aromatic fiber

Huckel rule heterocyclic aromatic compounds

Hydrogenation of Heterocyclic Aromatic Compounds

Liquid Crystalline Aromatic Heterocyclic Polymers

Methanol aromatic heterocyclics

Nine-membered heterocycles, aromaticity

Nitration of aromatic and heterocyclic compounds

Nitrogen heterocycles aromatic six-membered, regioselective

Non-Aromatic Heterocycles with sp2 Ring Carbons

Non-aromatic Boron Heterocyclics

Nucleophiles, reaction with aromatic heterocyclic bases

Nucleophilic aromatic heterocycles allylation

Nucleophilic aromatic heterocycles ambident

Nucleophilic aromatic heterocycles ambident palladium -catalyzed

Nucleophilic aromatic heterocycles palladium -catalyzed allylation

Nucleophilic aromatic heterocycles, ambident palladium -catalyzed allylation

Nucleophilic aromatic heterocyclic systems

Nucleophilic aromatic of heterocyclic systems

Nucleophilic aromatic substitution heterocyclic systems

Organometallic heterocycles aromaticity

Other Aromatic Six-Membered Ring Heterocyclics

Other aromatic hydrocarbons and heterocyclic compounds

Pi-Deficient Aromatic Heterocycles

Pi-Excessive Aromatic Heterocycles

Polycyclic aromatic heterocycles

Polycyclic aromatic oxygen heterocycles

Polycyclic aromatic sulfur heterocycles

Polyesters aromatic heterocycle containing

Polyimides aromatic heterocyclic

Polymers aromatic heterocyclic type

Polynuclear Aromatic Hydrocarbons and Heterocyclic Compounds

Polyphenylenes, aromatic heterocyclic

Protection for Imidazoles, Pyrroles, Indoles, and other Aromatic Heterocycles

Pyridine and Pyrrole Two Aromatic Heterocycles

Radical-nucleophilic aromatic substitution heterocyclic synthesis

Reactions heterocyclic aromatic compounds

Reactivity of Aromatic Heterocycles

Reduction of Heterocyclic Aromatics

Reduction of Non-aromatic Heterocycles Containing the C N Function

Reductions of Heterocyclic N-Oxides and Aromatic Nitro Groups

Regioselective substitution in aromatic six-membered nitrogen heterocycles

Regioselective substitution in aromatic sixmembered nitrogen heterocycles

Regioselective, in aromatic six-membered nitrogen heterocycles

Replacement of NH2 in aromatic or heterocyclic compounds by fluorine (Schiemann reaction)

Selenophens Fused to Six-membered Heterocyclic Aromatic Rings

Six-membered aromatic heterocycles can have oxygen in the ring

Some classic aromatic heterocycle syntheses

Structures and Spectroscopic Properties of Aromatic Heterocycles

Substitution in Heterocyclic Aromatic Compounds

Substitutions of Aromatic Heterocycles

Sulfur-containing aromatic heterocycles

Synthesis heterocyclic aromatic compounds

Synthesis of Aromatic Heterocycles

The Palladium-Catalyzed Synthesis of Aromatic Heterocycles

Three-membered heterocycles aromaticity

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