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Nucleophile nitrogen

Most syntheses of nitrogen heterocycles involve substitution and/or condensation reactions of nitrogen nucleophiles with difunctional halides or carbonyl compounds. Common nitrogen reagents are ... [Pg.147]

Regioselectivity becomes important, if unsymmetric difunctional nitrogen components are used. In such cases two different reactions of the nitrogen nucleophile with the open-chain educt may be possible, one of which must be faster than the other. Hydrazone formation, for example, occurs more readily than hydrazinoLysis of an ester. In the second example, on the other hand, the amide is formed very rapidly from the acyl chloride, and only one cyclization product is observed. [Pg.149]

Carbamates are allylated in the presenee of strong bases in DMSO or HMPA[197], Phthalimide (320) and succimide are allylated with the allyl-isoureu 321 at room temperature or the allylic acetate 322 at 100 C[I98.I99], Di-/-butyl iminodicarbonate is used as a nitrogen nucleophile[200]. [Pg.333]

In acid the nitnle is protonated on nitrogen Nucleophilic addition of water yields an imino acid... [Pg.1241]

The polymerization of ethyleneimine (16,354—357) is started by a catalyticaHy active reagent (H or a Lewis acid), which converts the ethyleneimine into a highly electrophilic initiator molecule. The initiator then reacts with nitrogen nucleophiles, such as the ethyleneimine monomer and the subsequendy formed oligomers, to produce a branched polymer, which contains primary, secondary, and tertiary nitrogen atoms in random ratios. Termination takes place by intramolecular macrocycle formation. [Pg.11]

Nitrogen nucleophiles used to diplace the 3 -acetoxy group include substituted pyridines, quinolines, pyrimidines, triazoles, pyrazoles, azide, and even aniline and methylaniline if the pH is controlled at 7.5. Sulfur nucleophiles include aLkylthiols, thiosulfate, thio and dithio acids, carbamates and carbonates, thioureas, thioamides, and most importandy, from a biological viewpoint, heterocycHc thiols. The yields of the displacement reactions vary widely. Two general approaches for improving 3 -acetoxy displacement have been reported. One approach involves initial, or in situ conversion of the acetoxy moiety to a more facile leaving group. The other approach utilizes Lewis or Brmnsted acid activation (87). [Pg.32]

Kinetic data on acetate displacement from C-3 using a number of sulfur and nitrogen nucleophiles in aqueous solution at near neutral pH demonstrate that the reaction proceeds by an 5 1 mechanism (B-72MI51004). The intermediate in this reaction is depicted as a dipolar allylic carbonium ion (9) with significant charge delocalization. Of particular significance in this regard is the observation that the free carboxylate at C-4 is required since... [Pg.288]

Formal replacement of one of the bulky halogens in polyhalogenofluoro-ethanes by nitrogen nucleophiles occurs through the intermediate formation of fluorinated olefins [91, 92] (see equation 47) (equation 79). [Pg.466]

The replacement of reactive aromatic fluonne by nitrogen nucleophiles is a well-known process for the preparation of aromatic amines The aromatic fluonne IS activated by the presence of electron-withdrawing substituents on the aromatic ring, especially in ortho and para positions [57 38, 39] (equations 25-27)... [Pg.508]

Reaction at position 4 of perfluotopyndme thus occurs readily with nitrogen nucleophiles, as exemplified by its reactions with sodium azide and with hydroxyl-amme [75, 76] (equation 39)... [Pg.513]

Phosphorus nucleophiles have received little attention compared with nitrogen nucleophiles in reactions with fluonnated systems Yields with phosphorus nucleophiles are sometimes low, but interesting materials are obtained [80, 81] (equations 42 and 43). [Pg.514]

In its overall design, this procedure is similar- to the Gabriel synthesis a nitrogen nucleophile is used in a carbon-nitrogen bond-fonning operation and then converted to an fflnino group in a subsequent transfor-mation. [Pg.931]

Amines can be prepared by means of Sn2 reactions involving alkyl halides and nitrogen nucleophiles. [Pg.204]

One potential problem with this procedure is that the product can sometimes act as a nitrogen nucleophile, and multiple substitutions may then occur. It is useful, therefore, to be able to distinguish the relative nucleophilicity of different amines. [Pg.204]


See other pages where Nucleophile nitrogen is mentioned: [Pg.78]    [Pg.320]    [Pg.321]    [Pg.434]    [Pg.4]    [Pg.184]    [Pg.411]    [Pg.287]    [Pg.111]    [Pg.153]    [Pg.153]    [Pg.158]    [Pg.159]    [Pg.160]    [Pg.288]    [Pg.289]    [Pg.546]    [Pg.546]    [Pg.546]    [Pg.617]    [Pg.617]    [Pg.618]    [Pg.618]    [Pg.618]    [Pg.754]    [Pg.756]    [Pg.792]    [Pg.887]    [Pg.492]    [Pg.557]   
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See also in sourсe #XX -- [ Pg.572 ]




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1.5- Dienes nitrogen nucleophiles

5 -Oxazolones nitrogen nucleophiles

Acetates nitrogen nucleophilic

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

Acylation of Nucleophilic Oxygen and Nitrogen Groups

Addition of Carbon, Oxygen, Nitrogen, and Sulfur Nucleophiles

Addition of Nitrogen Nucleophiles

Addition of Oxygen and Nitrogen Nucleophiles

Alkaloid syntheses nitrogen nucleophiles

Alkenes nitrogen nucleophiles

Alkynes nitrogen nucleophiles

Allenes nitrogen nucleophiles

Allyl chloride reactions with nitrogen nucleophiles

Allylamines nitrogen nucleophiles

Allylation nitrogen nucleophiles

Allylation of Oxygen and Nitrogen Nucleophiles

Amides cyclization reactions, nitrogen nucleophiles

Ammonia and Some Other Common Nitrogen Nucleophiles

Aromatic nitrogen heterocycles oxygen nucleophiles

Arylation of Nitrogen Nucleophiles

Asymmetric nitrogen nucleophile

Aziridine cyclization reactions, nitrogen nucleophiles

By nitrogen nucleophile

By nitrogen nucleophile fluonne

Carbamates nitrogen nucleophile cyclization

Carbon nitrogen nucleophile attack

Carbon-nitrogen bonds nucleophilic properties

Carbonyl compounds with nitrogen nucleophiles

Carbopalladation nitrogen nucleophiles

Cascade carbopalladation nitrogen nucleophiles

Cascade reactions nitrogen nucleophiles

Conjugate Addition of Nitrogen Nucleophiles

Conjugated diene complexes of nitrogen nucleophiles

Double bond formation nitrogen nucleophiles

Enynes of nitrogen nucleophiles

Epoxidation with nitrogen nucleophiles

Epoxides nitrogen nucleophiles

Epoxides, vinyl reaction with nitrogen nucleophiles

Group 15 Nucleophiles. Nitrogen

Heteroatomic coupling nitrogen nucleophiles

Imines nitrogen nucleophiles

Intermolecular reactions nitrogen nucleophile attacks

Intermolecular reactions nitrogen nucleophiles

Intramolecular delivery of a nitrogen nucleophile

Intramolecular processes nitrogen nucleophiles

Lactam synthesis nitrogen nucleophiles

Lactone synthesis nitrogen nucleophiles

Metal cyanides nitrogen nucleophiles

Naphthyridines reactivity of, toward nitrogen nucleophiles

Naphthyridines reactivity toward nitrogen nucleophiles

Nitrogen and Other Heteroatom Nucleophiles

Nitrogen as a nucleophile amides

Nitrogen as a nucleophile ammonium salts, amines

Nitrogen heterocycles Nucleophilic heteroaromatic substitution

Nitrogen isotope effects, nucleophilic

Nitrogen isotope effects, nucleophilic reactions

Nitrogen nucleophiles

Nitrogen nucleophiles

Nitrogen nucleophiles addition reactions

Nitrogen nucleophiles allylic derivatives

Nitrogen nucleophiles aromatic nucleophilic substitution

Nitrogen nucleophiles arylation

Nitrogen nucleophiles catalysis, intramolecular attacks

Nitrogen nucleophiles containing

Nitrogen nucleophiles cyclization

Nitrogen nucleophiles cycloaddition processes

Nitrogen nucleophiles formation

Nitrogen nucleophiles inter-intramolecular reactions

Nitrogen nucleophiles intra-intermolecular reactions

Nitrogen nucleophiles intramolecular reactions

Nitrogen nucleophiles mechanisms

Nitrogen nucleophiles natural products synthesis

Nitrogen nucleophiles nitro substrates

Nitrogen nucleophiles nucleophilic substitution

Nitrogen nucleophiles oxidative addition

Nitrogen nucleophiles processes

Nitrogen nucleophiles reactions

Nitrogen nucleophiles, 184 (Table

Nitrogen nucleophiles, 184 (Table addition

Nitrogen nucleophiles, Tsuji-Trost reaction

Nitrogen nucleophiles, addition

Nitrogen nucleophiles, addition solvent effect

Nitrogen nucleophiles, addition steric effect

Nitrogen nucleophiles, conjugate

Nitrogen nucleophiles, reactions with

Nitrogen nucleophiles, reactions with aryne

Nitrogen nucleophiles, reactions with naphthyridines

Nitrogen nucleophilic aliphatic substitution

Nitrogen nucleophilic substitution

Nitrogen-bonded substituents nucleophilic reactions

Nitrogen-containing nucleophile

Nucleophile-substrate interaction nitrogen reaction

Nucleophiles nitrogen-based

Nucleophiles nitrogen-centered

Nucleophiles saturated nitrogen heterocycles

Nucleophilic Additions to Unsaturated Nitrogen

Nucleophilic Attack at Ring Nitrogen

Nucleophilic Substitution at the Nitrogen, Phosphorus, and Sulfur Centers

Nucleophilic addition nitrogen nucleophiles

Nucleophilic addition nitrogen-containing nucleophiles

Nucleophilic addition reactions nitrogen nucleophiles

Nucleophilic addition reactions with nitrogen nucleophiles

Nucleophilic imidazole ring nitrogen

Nucleophilic imidazole ring nitrogenous compounds

Nucleophilic nitrogen

Nucleophilic nitrogen atom

Nucleophilic substitution activation by nitrogenous substituents

Nucleophilic substitution nitrogen nucleophile cyclization

Nucleophilic substitution of azines, activation by azine-nitrogen

Nucleophilic substitution process nitrogen compounds

Nucleophilic substitution—continued hydrogen bonding to azine-nitrogen

Nucleophilic substitution—continued ring nitrogens, influence

Nucleophilic with nitrogen nucleophiles

Nucleophilicity nitrogen nucleophiles

Nucleophilicity nitrogen nucleophiles

Of epoxides with nitrogen nucleophiles

Of naphthyridines toward nitrogen nucleophiles

Oxirans with nitrogen nucleophile

Oxirans with nitrogen nucleophiles

Reaction with Nitrogen and Phosphorus Nucleophiles

Reactions of Aldehydes and Ketones with Nitrogen Nucleophiles

Reactivity of, toward nitrogen nucleophiles

Rearrangement nitrogen-nucleophiles

Replacement Reactions with Nitrogen Nucleophiles

Ring opening nitrogen nucleophiles

Ring opening reactions with nitrogen nucleophiles

Ring opening with nitrogen nucleophile

Ring opening with nitrogen nucleophiles

Ring systems cyclization, nitrogen nucleophiles

Ring with nitrogen-based nucleophiles

Ring-Opening meso-Oxabicyclic Alkenes with Nitrogen-Based Nucleophiles

Stille coupling nitrogen nucleophiles

Transmetallation nitrogen nucleophiles

Triple bond formation nitrogen nucleophiles

With Nitrogen Nucleophiles

With Oxygen and Nitrogen Nucleophiles

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