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Nitrogen heterocyclic

The aromatic extracts are black materials, composed essentially of condensed polynuclear aromatics and of heterocyclic nitrogen and/or sulfur compounds. Because of this highly aromatic structure, the extracts have good solvent power. [Pg.291]

In the case of lubricant dispersants, the polar part is organic (amine, polyamine, heterocyclic nitrogen compounds, polyglycol). [Pg.360]

Indole is classified as a 7c-excessive aromatic compound. It is isoelectronic with naphthalene, with the heterocyclic nitrogen atom donating twm of the ten 7t-electrons. [Pg.2]

Quaternarj salts are obtained by alkylation of selenazole bases, the heterocyclic nitrogen atom playing the role of nucleophile with regard to the electrophilic carbon of the alkylating, agent. [Pg.256]

Methylation takes place on the selenium (73). in contrast to the thiazolidines where it occurs on the heterocyclic nitrogen (75). [Pg.268]

With heteroaromatic substrates it is possible to prepare, for example, thiazolyipyridines. It is noteworthy that basic solvents (e.g., heterocyclic nitrogen compounds) increase the yield of substitution by a cage effect (see Tables III-37 and III-38) (208). [Pg.373]

These contracted names of heterocyclic nitrogen compounds are retained as alternatives for systematic names, sometimes with indicated hydrogen. In addition, names of 0x0 derivatives of fully saturated nitrogen heterocycles that systematically end in -idinone are often contracted to end in -idone when no ambiguity might result. For example. [Pg.34]

Nitrogen fluoride Nitrogen heterocycles nitrogen implantation Nitrogen monoxide Nitrogen mustards Nitrogen oxide... [Pg.680]

Other Heterocyclic Nitrogen Derivative Herbicides. The herbicides in this group are heterocycHc nitrogen derivatives that do not readily fall into one of the previously discussed groups. They have a wide range of uses and properties. Most of these herbicides are used for selective, pre-and/or post-emergence weed control. Amitrole is used for post-emergence, nonselective weed control in non-croplands and also as an aquatic herbicide (2,296). [Pg.53]

The normal pattern of coupling constants for aromatic six-membered rings is found in the heterocyclic aza systems, except that the ortho coupling to a proton a to a heterocyclic nitrogen is reduced from 7-8 Hz to 4.5-6 Hz. The J2.3 of pyrylium salts is still lower... [Pg.10]

The removal of a hydrogen atom from a heterocyclic nitrogen atom of azolones by nucleophiles acting as bases, e.g. (14) (15), gives mesomeric anions, e.g. (15) <-> (16) <->... [Pg.43]

The reader is referred to previous reviews for historical aspects and early work. For condensed quinazoline systems, The Chemistry of Heterocyclic Compoundsr—Six Membered Heterocyclic Nitrogen Compounds with Four Condensed Rings should be consulted. [Pg.254]

It has also been suggested to treat various modified heterocyclic nitrogen atoms in the same manner. Thus, cr-values have been proposed for the protonated aza nitrogen, N+H, and for the N+0 ... [Pg.217]

Spectroscopic evidence indicates that protonation of 2-fluoro-and 2-chloro-quinoline is not appreciable in O.OlJf aqueous hydrochloric acid. Protonation becomes evident in more strongly acidic solution in the case of the chloro compound without any accompanying decomposition, but the fluoro compound hydrolyzes to carbostyril under the latter conditions. The hydrolysis is acid-catalyzed, but it is doubtful whether protonation on the heterocyclic nitrogen is responsible, owing to its low basicity (presumably below that for the chloro compound). An alternative explanation in this case would be hydrogen bond formation with fluorine, Ar—F. .. H-O+H2. [Pg.297]

Thus the activity of the methyl groups in this reaction decreases in the series C-4 > C-5 > C-3. This may be considered as evidence of the inhibiting effect of the nitrogen hetero atom on the radical substitution in methyl groups at C-3 and, to a lesser extent, at C-5 (compare the effect of the heterocyclic nitrogen in the pyridine and azole series ) and of a similar effect of the electron-accepting substituents in the 4-position on the methyl group at C-5. [Pg.393]

Shaw concluded that hydrogenation of 3-alkyl-4-aminomethylene isoxazol-5-ones (184) in the presence of palladium catalyst resulted in the saturation of either the endocyclic double carbon-nitrogen bond or the exocyclic double C—C bond with the retention of the heterocyclic nitrogen-oxygen bond. Recent data reported by Kochetkov et al. on the properties, and in particular on hydrogenation, of isoxazolid-5-ones - indicate, however, that Shaw had probably ob-... [Pg.417]

The use of urethanes of phenothiazines involving the heterocyclic nitrogen (22, 45) as a means of attaching the side chain is discussed above. Although these intermediates apparently do not possess antipsychotic activity, two compounds of this general class, endowed with somewhat more complex appendages, do exhibit... [Pg.389]

Compounds with triple bonds, i.e. acetylenic compounds, continue to receive attention. Patents have been filed for mixtures of propargyl alcohol with, for example, cellosolve + a phenol formaldehyde resin + tar bases heterocyclic nitrogen compounds + acetylenic + dialkylthiourea or a quaternary + antimony oxide . [Pg.800]

Heterocyclic amines—compounds in which the nitrogen atom occurs as part of a ring—are also common, and each different heterocyclic ring system has its own parent name. The heterocyclic nitrogen atom is always numbered as position 1. [Pg.918]

Aminopyridines, aminopyridine oxides, and 3-aminoquinoline are obviously diazotized by analogous mechanisms. Kalatzis (1967 b) studied the diazotization of 4-aminopyridine over a very large range of acid concentrations (0.0025-5.0 m HC104). This compound is comparable to 2-aminothiazole in its acid-base properties the heterocyclic nitrogen is easily protonated at pH 10, whereas the amino group is a very weak base (pKa = -6.5). Therefore, the kinetics indicate that the (mono-protonated) 4-aminopyridinium ion reacts with the nitrosyl ion. The... [Pg.53]

Neither the 2- nor 4-aminopyridine-l-oxides nor their substitution products can be protonated at the heterocyclic nitrogen. The findings regarding the diazotization kinetics of these compounds indicate that, under the reaction conditions studied by Kalatzis and Mastrokalos (1977), two simultaneous mechanisms take place. In the first of these, nitrosyl ions attack the free amine, whereas in the second they attack the protonated amine. [Pg.53]

R represents the thiazole ring and the thiazole ring protonated at the heterocyclic nitrogen atom. The subscripts and 0 refer to equilibrium and initial concentrations, respectively. [Pg.63]

The base of the aniline derivative has zero charge, and therefore H0 has to be used in 2-aminothiazole the heterocyclic nitrogen is protonated first and at much lower acidities than is the amino group (see Sec. 3.2). The protonation of the amino group of a cationic species therefore has to be treated using the H+ function (Rochester, 1970). [Pg.64]

In the scientific sector, the understanding of the generally higher reactivity of heteroaromatic diazo components relative to that of aromatic diazonium salts has increased. The number of heterocyclic nitrogen atoms in azolediazonium ions has a marked influence on the N-H acidity of these ions. The pvalues of a series of such ions in aqueous solution at 0 °C (Scheme 12-4) indicate that the electrophilicity of the diazonio group in these compounds increases with the number of nitrogen atoms in the ring. ... [Pg.309]

A true intramolecular proton transfer in the second step of an azo coupling reaction was found by Snyckers and Zollinger (1970a, 1970b) in the reaction of the 8-(2 -pyridyl)-2-naphthoxide ion (with the transition state 12.151). This compound shows neither a kinetic deuterium isotope effect nor general base catalysis, in contrast to the sterically similar 8-phenyl-2-naphthoxide ion. Obviously the heterocyclic nitrogen atom is the proton acceptor. [Pg.362]


See other pages where Nitrogen heterocyclic is mentioned: [Pg.303]    [Pg.66]    [Pg.41]    [Pg.413]    [Pg.327]    [Pg.283]    [Pg.418]    [Pg.295]    [Pg.227]    [Pg.10]    [Pg.16]    [Pg.52]    [Pg.53]    [Pg.104]    [Pg.106]    [Pg.277]    [Pg.88]    [Pg.138]   
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See also in sourсe #XX -- [ Pg.320 ]

See also in sourсe #XX -- [ Pg.476 ]

See also in sourсe #XX -- [ Pg.269 ]




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2- Hydroxy-nitrogen heterocycles

2- Hydroxy-nitrogen heterocycles complexation reactions

Acetylenecarboxylic esters, reactions with nitrogen-containing heterocycles

Acetylenecarboxylic esters, reactions with nitrogen-containing heterocycles through nucleophilic additions

Acridines, Carbazoles and Other Polycyclic Nitrogen Heterocycles

Addition to nitrogen heterocyclic aromatic compounds

Additional Boron-Nitrogen Heterocycles

Additional Organoboron-Nitrogen Heterocycles

Advances in amination of nitrogen heterocycles

Amination nitrogen heterocycles

Amination of nitrogen heterocycles

Amination of nitrogen heterocycles, advances

Amines and Nitrogen Heterocyclic Compounds

Amines and nitrogen heterocycles

Amines nitrogen heterocycles

Aromatic heterocyclic nitrogen compounds

Aromatic nitrogen heterocycles

Aromatic nitrogen heterocycles oxygen nucleophiles

Aromatic six-membered nitrogen heterocycles

Aromatic six-membered nitrogen heterocycles regioselective substitution

Aromaticity nitrogen heterocycles

Asymmetric Synthesis of Nitrogen Heterocycles

Azo dyes heterocyclic nitrogen donor

Basicity heterocycles, nitrogen

Basicity of nitrogen heterocycles

Benzofused nitrogen heterocycles

Bicyclo nitrogen heterocycles

Carbenes nitrogen-free heterocyclic

Chemistry of unsaturaled nitrogen heterocyclic

Chemistry of unsaturated nitrogen heterocyclic

Chiral nitrogen-containing heterocycles

Claisen rearrangements in nitrogen heterocycles

Claisen rearrangements in nitrogen heterocyclic systems

Claisen rearrangements nitrogen heterocycles with

Claisen rearrangements nitrogen heterocyclic systems

Claisen rearrangements, in nitrogen heterocyclic

Complex metal hydrides, reduction nitrogen heterocycles with

Costero, A. M., The Chemistry of Unsaturated Nitrogen Heterocyclic Compounds

Covalent hydration in nitrogen heterocycles

Cyclization reactions nitrogen heterocycles

Cyclizations nitrogen heterocycles

Dibenzo Heterocycles Containing One Ring Nitrogen Atom

El Khadem, Hassan, Synthesis of Nitrogen Heterocycles from Saccharide

El Khadem, Hassan, Synthesis of Nitrogen Heterocycles from Saccharide Derivatives

Electron-deficient nitrogen heterocycles

Enamines cycloaddition with nitrogen heterocycles

Esters from nitrogen heterocycles

Ethyl acetate heterocyclic nitrogens

Five-Membered Selenium-Nitrogen Heterocycles

Five-membered nitrogen heterocycles

Formation of Five-membered Nitrogen Heterocycles

Formation of Heterocycles Containing Nitrogen and Oxygen

Formation of Higher-membered Nitrogen Heterocycles

Formation of Six-membered Nitrogen Heterocycles

Formation of Three-membered Nitrogen Heterocycles

Four-membered Heterocycles containing a Single Nitrogen, Oxygen or Sulfur Atom

Fused nitrogen heterocycles

Fused to other Nitrogen-containing Heterocycles

Generation the vicinity of heterocyclic nitrogen

Generation vicinity of heterocyclic nitrogen atoms

Heterocycles Containing Nitrogen, Oxygen, and Sulphur

Heterocycles Containing a Ring-Junction Nitrogen (Bridgehead Compounds)

Heterocycles Containing a Ring-junction Nitrogen

Heterocycles can have many nitrogens but only one sulfur or oxygen in any ring

Heterocycles nitrogen containing, acridine

Heterocycles with three nitrogen atoms

Heterocycles with three nitrogen atoms reviews

Heterocyclic aromatic compounds nitrogen atom

Heterocyclic aromatic nitrogen

Heterocyclic bridgehead nitrogen

Heterocyclic compounds Nitrogen heterocycles)

Heterocyclic compounds of nitrogen

Heterocyclic ligands, nitrogen

Heterocyclic nitrogen compounds

Heterocyclic nitrogen compounds basic

Heterocyclic nitrogen compounds metal complexes

Heterocyclic nitrogen compounds, cytochrome

Heterocyclic nitrogen donor ligands

Heterocyclic nitrogen herbicides

Heterocyclic synthesis nitrogen-containing

Hydrogenation of Nitrogen Heterocycles

Hydrogenolysis of Nitrogen Heterocycles

In amination of nitrogen heterocycles

In nitrogen heterocycles

In nitrogen heterocyclic systems

Index nitrogen heterocyclic compounds

Iridium complexes nitrogen heterocycles

Iron-Catalyzed Synthesis of Nitrogen-Containing Heterocycles

Keay, J. G., The Reduction of Nitrogen Heterocycles with Complex Metal

Lyle, R. E., Anderson, P. S., The Reduction of Nitrogen Heterocycles with Complex

Macrocyclization nitrogen heterocycles

Mechanism nitrogen heterocycles

Medicine nitrogen heterocycles

Medium-sized-ring Nitrogen-containing Heterocycles

Metal-nitrogen bonding heterocycles

New Nitrogen Heterocycles

Nitriles Nitrogen heterocycles, synthesis from

Nitrogen Heterocycles (Except Alkaloids)

Nitrogen and Oxygen Heterocycles

Nitrogen and Sulfur Heterocycles

Nitrogen and Sulphur Heterocycles

Nitrogen heterocycles

Nitrogen heterocycles Conformational equilibria in saturated sixmembered rings

Nitrogen heterocycles Nuclear magnetic resonance spectroscopy

Nitrogen heterocycles Nucleophilic heteroaromatic substitution

Nitrogen heterocycles advances in amination

Nitrogen heterocycles aromatic six-membered, regioselective

Nitrogen heterocycles compounds)

Nitrogen heterocycles containing carbonyl

Nitrogen heterocycles containing carbonyl groups, unsaturated, chemistry

Nitrogen heterocycles covalent hydration

Nitrogen heterocycles esters with

Nitrogen heterocycles examples

Nitrogen heterocycles from

Nitrogen heterocycles hydrides

Nitrogen heterocycles mass spectra

Nitrogen heterocycles photochemistry

Nitrogen heterocycles preparation

Nitrogen heterocycles principles

Nitrogen heterocycles radicals from

Nitrogen heterocycles reactions of acetylenecarboxylic

Nitrogen heterocycles reactions of acetylenecarboxylic esters

Nitrogen heterocycles reactions of acetylenecarboxylic esters with

Nitrogen heterocycles reactions with acetylenic esters

Nitrogen heterocycles reduction of, with complex metal

Nitrogen heterocycles six-membered rings

Nitrogen heterocycles substitution

Nitrogen heterocycles, anionic

Nitrogen heterocycles, anionic complexes

Nitrogen heterocycles, eight-membered

Nitrogen heterocycles, formation

Nitrogen heterocycles, literature

Nitrogen heterocycles, literature reviews

Nitrogen heterocycles, literature survey

Nitrogen heterocycles, reduction of, with

Nitrogen heterocycles, reduction of, with complex metal hydrides

Nitrogen heterocycles, saturated, reactions

Nitrogen heterocycles, synthesis

Nitrogen heterocycles, synthesis from

Nitrogen heterocycles, synthesis from saccharide derivatives

Nitrogen heterocycles, unsaturated, synthesis

Nitrogen heterocyclic bases

Nitrogen heterocyclic compounds dependence

Nitrogen heterocyclic compounds isoquinoline

Nitrogen heterocyclic systems, Claisen

Nitrogen, heterocyclic compounds imidazole

Nitrogen, heterocyclic compounds indole

Nitrogen, heterocyclic compounds piperazine

Nitrogen, heterocyclic compounds piperidine

Nitrogen, heterocyclic compounds pyrazole

Nitrogen, heterocyclic compounds pyridine

Nitrogen, heterocyclic compounds pyrrole

Nitrogen, heterocyclic compounds pyrrolidine

Nitrogen, heterocyclic compounds quinoline

Nitrogen- and Sulphur-containing Heterocycles

Nitrogen-Based Delocalized and Heterocyclic Ligands

Nitrogen-Only Heterocycles

Nitrogen-based heterocyclic radicals

Nitrogen-centered heterocyclic radicals

Nitrogen-containing heterocycle synthesis

Nitrogen-containing heterocycle synthesis compounds

Nitrogen-containing heterocycle synthesis five-membered ring heterocycles

Nitrogen-containing heterocycle synthesis seven-membered ring heterocycles

Nitrogen-containing heterocycles

Nitrogen-containing heterocyclic compounds

Nitrogen-containing heterocyclic systems

Nitrogen-containing heterocyclics

Nitrogen-heterocyclic carbene

Nitrogenated lewis bases heterocycles, synthesis

Non-heterocyclic nitrogen centres

Nucleophiles saturated nitrogen heterocycles

Of nitrogen-containing heterocycles

Of sp2-carbanionic centers in the vicinity heterocyclic nitrogen atoms

Of unsaturated nitrogen heterocyclic

Of unsaturated nitrogen heterocyclic compounds containing carbonyl

Of unsaturated nitrogen heterocyclic groups

Other Nitrogen Heterocyclics

Other heterocyclic nitrogen centres

Oxygen-nitrogen heterocycles

Oxygen-nitrogen heterocycles photochemistry

Palladium nitrogen-containing heterocycles

Pd-Catalyzed Synthesis of Nitrogen-Containing Heterocycles

Perfluorinated nitrogen-containing heterocycles

Phosphines, nitrogen heterocycle adducts

Phosphorus-nitrogen heterocycles

Photochemistry of nitrogen-containing heterocycles

Polycyclic fused nitrogen heterocycles

Preparation of Magnesiated Nitrogen-Heterocycles

Pyridine nitrogen heterocycles

Pyridines and related nitrogen heterocyclic (azabenzenoid) compounds

Quaternary nitrogen heterocycles

Reactions heterocyclic nitrogen atoms

Reactions of heterocyclic nitrogen atoms

Reduction of Heterocycles Containing One Nitrogen Atom

Reduction of Heterocycles Containing Three Nitrogen Atoms

Reduction of Heterocycles Containing Two Nitrogen Atoms

Reduction of nitrogen heterocycles with complex

Reductions of Other Heterocycles Containing One Nitrogen Atom

Regioselective substitution in aromatic six-membered nitrogen heterocycles

Regioselective substitution in aromatic sixmembered nitrogen heterocycles

Regioselective, in aromatic six-membered nitrogen heterocycles

Rh-Catalyzed Synthesis of Nitrogen-Containing Heterocycles

Saccharides, nitrogen heterocycles from

Saturated five-membered nitrogen heterocycles

Saturated five-membered nitrogen heterocycles reactions

Saturated five-membered nitrogen heterocycles synthesis

Selenium-nitrogen heterocycles

Seven-membered nitrogen heterocycle

Silver nitrogen-containing heterocycle

Silver-Catalyzed Synthesis of Nitrogen-Containing Heterocycles

Six-Membered Selenium-Nitrogen Heterocycles

Six-membered heterocycles nitrogen

Small ring nitrogen heterocycles

Sp2-Carbanionic centers in the vicinity heterocyclic nitrogen atoms, generation

Sugars nitrogen heterocycles from

Sulfur-Nitrogen Heterocycles

Sulfur/nitrogen-centered heterocyclic

Sulfur/nitrogen-centered heterocyclic radicals

Sulfur/nitrogen-centered heterocyclic radicals-thiazyls

Synthesis of Nitrogen Heterocycles via Pd-Catalyzed 1,3-Dipolar Cycloaddition Reactions

Synthesis of Nitrogen Heterocyclic Compounds

Synthesis of Nitrogen-Containing Heterocyclic (Z)-1,3-Dienes

Synthesis of Other Nitrogen Heterocycles

Synthesis of Quinoxalines from Various Fused Nitrogen-Containing Heterocycles Without a Pyrazine Fragment

Synthesis of five-membered nitrogen heterocycle

Synthesis of nitrogen heterocycles

Synthesis of nitrogen heterocycles from saccharide derivatives

Synthesis of six-membered nitrogen heterocycle

Tellurium-Nitrogen-Containing Heterocycles

Thiazoles and Related Sulfur-Nitrogen-Containing Heterocycles

Tin-nitrogen heterocycles

Transition nitrogen heterocycles

Unsaturated nitrogen heterocyclic

Unsaturated nitrogen heterocyclic chemistry

Unsaturated nitrogen heterocyclic compounds

Unsaturated nitrogen heterocyclic compounds containing carbonyl groups

Unsaturated nitrogen heterocyclic compounds containing carbonyl groups, chemistry

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