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With aromatic amines

Fischer-Hepp rearrangement The nitros-amines of aromatic secondary amines when treated with hydrochloric acid give nuclear substituted nitrosoamines. Among the benzene derivatives, if the para position is free the -NO group displaces the hydrogen atom there in naphthalene derivatives it enters the 1-position ... [Pg.175]

Aromatic primary amines differ markedly from aliphatic amines in their reaction with nitrous acid. Thus a cold aqueous solution of mono thylamine hydrochloride reacts with nitrous acid to give mainly the corresponding primary alcohol ... [Pg.182]

Nitrous acid does not react with aliphatic tertiary amines, such as triethyl-amine, (CaHj)aN, nor does it usually react with aromatic tertiary amines such as triphenylamine, (CaHj)aN, which contain three aryl groups. [Pg.204]

Diazonium salts couple readily with aromatic primary amines, giving diazoamino compounds. If for instance an aqueous solution of aniline sulphate is diazotised with a deficiency of nitrous acid, only part of it is converted into benzenediazonium sulphate and the latter then couples with the unchanged aniline to give diazoaminobenzene. The reaction is carried out at the opti-CeHsNHj.HjSO + HONO = CbHsNjHSO, + zHaO... [Pg.207]

Reactions with Amines and Amides. Hydroxybenzaldehydes undergo the normal reactions with aUphatic and aromatic primary amines to form imines and Schiff bases reaction with hydroxylamine gives an oxime, reaction with hydrazines gives hydrazones, and reactions with semicarbazide give semicarbazones. The reaction of 4-hydroxybenzaldehyde with hydroxylamine hydrochloride is a convenient method for the preparation of 4-cyanophenol (52,53). [Pg.505]

Nitro alcohols react with amines to form nitro amines. Such a reaction can be carried out with a wide variety of primary and secondary amines, both ahphatic and aromatic a basic catalyst is requited if aromatic amines are involved. The products of reactions between dihydric nitro alcohols and amines are nitrodiamines, many of which are good fungicides (qv). Dihydric nitro alcohols, primary amines, and formaldehyde react to yield nitrohexahydropyrimidines (4). Nitrohexahydropyrimidines can be reduced to the corresponding amines, some of which are good fungicides or bactericides, eg, hexetidine [141-94-6] (5-amino-l,3—bis(2-ethylhexyl)-5-methylhexahydropyrimidine). [Pg.61]

With amine initiators the so-called self-catalysed polyols are obtained, which are used in the formulation of rigid spray foam systems. The rigidity or stiffness of a foam is increased by aromatic initiators, such as Mannich bases derived from phenol, phenoHc resins, toluenediamine, or methylenedianiline... [Pg.347]

Primary and secondary aliphatic and aromatic amines react readily with thiiranes to give 2-mercaptoethylamine derivatives (Scheme 76) (76RCR25, 66CRV297). The reaction fails or gives poor yields with amines which are sterically hindered e.g. N,iV-dicyclohexylamine) or whose nitrogen atom is weakly basic e.g. N,A/ -diphenylamine). Aromatic amines are less reactive and higher reaction temperatures are usually required for them. The reaction mechanism is Sn2 and substituted thiiranes are attacked preferentially at the least hindered... [Pg.158]

On the basis of data obtained the possibility of substrates distribution and their D-values prediction using the regressions which consider the hydrophobicity and stmcture of amines was investigated. The hydrophobicity of amines was estimated by the distribution coefficient value in the water-octanole system (Ig P). The molecular structure of aromatic amines was characterized by the first-order molecular connectivity indexes ( x)- H was shown the independent and cooperative influence of the Ig P and parameters of amines on their distribution. Evidently, this fact demonstrates the host-guest phenomenon which is inherent to the organized media. The obtained in the research data were used for optimization of the conditions of micellar-extraction preconcentrating of metal ions with amines into the NS-rich phase with the following determination by atomic-absorption method. [Pg.276]

Aromatic tertiary amines ean also be used as part of the initiator system [58]. Glyeidyl methaerylate or methaerylie aeid have been used to hybridize acrylie adhesives based on this eure ehemistry with epoxies [59]. The epoxy funetionality is reaetive with the earboxylie aeid groups on the monomer. [Pg.836]

Another pathway for the aromatization of the cr -adducts was found in the reactions of 3-pyrrolidino-l,2,4-triazine 4-oxide 81 with amines. Thus the treatment of 1,2,4-triazine 4-oxide 81 with ammonia leads to 5-amino-1,2,4-triazine 4-oxides 54—products of the telesubstitution reaction. In this case the cr -adduct 82 formed by the addition of ammonia at position 5 of the heterocycle undergoes a [l,5]sigmatropic shift resulting in 3,4-dihydro-1,2,4-triazine 83, which loses a molecule of pyrrolidine to yield the product 54. This mechanism was supported by the isolation of the key intermediates for the first time in such reactions—the products of the sigmatropic shift in the open-chain tautomeric form of tiiazahexa-triene 84. The structure of the latter was established by NMR spectroscopy and X-ray analysis. In spite of its open-chain character, 84 can be easily aromatized by refluxing in ethanol to form the same product 54 (99TL6099). [Pg.282]

Qiu et al. [11] reported that the aromatic tertiary amine with an electron-rich group on the N atom would favor nucleophilic displacement and thus increase the rate of decomposition of diacyl peroxide with the result of increasing the rate of polymerization (Table 1). They also pointed out that in the MMA polymerization using organic peroxide initiator alone the order of the rate of polymerization Rp is as follows ... [Pg.228]

Besides aromatic tertiary amines, the aliphatic cyclic tertiary amines such as N-methyl(or ethyl) morpholine can also be used in coupling with BPO to enhance the Rp of MMA polymerization [20], Since the... [Pg.229]

Route (1) is referred to as local excitation and route (2) as CTC excitation. It has been observed that the different routes bring about the polymerization of AN with different kinetic behaviors. A 365-nm light will irradiate the CTC only, and in this case the rate of polymerization for different aromatic tertiary amines descends in the following order ... [Pg.237]

This order agrees with that of quenching constant (Aqr) vaiues of the fluorescence of amines by AN. That is, the easier the reaction between an excited aromatic tertiary amine and the ground state AN, the faster the initiation. [Pg.237]

The method can be applied to most phenols substituted in the ortho or meta position and to phenols substituted in the para position by OH or OCH3 groups most other substituents in the para position inhibit the reaction. Aromatic primary amines unsubstituted in the para position interfere and must be removed if possible before commencing the determination by extraction with acid. [Pg.708]

Z)-compounds are formed in reactions with hydroxide, methoxide, cyanide, and sulfite ions, whereas (ii)-compounds are formed in most reactions with amines (formation of triazenes) and with diazo coupling components such as phenols and aromatic tertiary amines. [Pg.157]

The parent, unsubstituted isochromanone has been caused to react with a variety of aromatic amines to prepare Ar-substituted 1,4-dihydro-3(2.ff)-isoquinolones,4 and with amines to give amides.5 The 6,7-methylenedioxy-3-isochromanone was an intermediate in the synthesis of protopine and its allied alkaloids,6 and for the synthesis of the berberine ring system.7 The 6-methoxy analog was prepared as a potential intermediate in a camptothecin synthesis8 and 8-methoxy-4,5,6,7-tetramethyl-3-isochromanonc was an intermediate in the synthesis of sclerin.9 The compound herein described was the basis of a facile synthesis of ( l )-xylopmins,10 and its reaction with hydrazine has been reported.11... [Pg.47]

The reaction of arylbromides with amines affords mostly the corresponding aromatic hydrocarbon by using palladium catalysts, but the expected substituted anilines are formed in good yields by using a nickel (II) catalyst. [Pg.240]

The reaction of diazo compounds with amines is similar to 10-15. The acidity of amines is not great enough for the reaction to proceed without a catalyst, but BF3, which converts the amine to the F3B-NHR2 complex, enables the reaction to take place. Cuprous cyanide can also be used as a catalyst. The most common substrate is diazomethane, in which case this is a method for the methylation of amines. Ammonia has been used as the amine but, as in the case of 10-44, mixtures of primary, secondary, and tertiary amines are obtained. Primary aliphatic amines give mixtures of secondary and tertiary amines. Secondary amines give successful alkylation. Primary aromatic amines also give the reaction, but diaryl or arylalkyl-amines react very poorly. [Pg.504]

Another hydroxylation reaction is the Elbs reaction In this method, phenols can be oxidized to p-diphenols with K2S20g in alkaline solution. Primary, secondary, or tertiary aromatic amines give predominant or exclusive ortho substitution unless both ortho positions are blocked, in which case para substitution is found. The reaction with amines is called the Boyland-Sims oxidation. Yields are low with either phenols or amines, generally under 50%. The mechanisms are not clear, but for the Boyland-Sims oxidation there is evidence that the S20 ion attacks at the ipso position, and then a migration follows. ... [Pg.724]

Other compounds with nitrogen-nitrogen bonds have been used instead of diazonium salts. Among these are N-nitroso amides [ArN(NO)COR], triazenes, and azo compounds. Still another method involves treatment of an aromatic primary amine directly with an alkyl nitrite in an aromatic substrate as solvent. ... [Pg.929]


See other pages where With aromatic amines is mentioned: [Pg.151]    [Pg.151]    [Pg.280]    [Pg.351]    [Pg.559]    [Pg.660]    [Pg.540]    [Pg.565]    [Pg.277]    [Pg.351]    [Pg.425]    [Pg.456]    [Pg.364]    [Pg.42]    [Pg.65]    [Pg.319]    [Pg.108]    [Pg.41]    [Pg.88]    [Pg.23]    [Pg.590]    [Pg.705]    [Pg.713]   
See also in sourсe #XX -- [ Pg.96 , Pg.269 , Pg.435 ]




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Aldehydes, reaction with aromatic amines

Amidation, of isocyanic acid with bromoaniline and other aromatic amines

Aromatic C-N Bond Formation with Non-Amine Substrates and Ammonia Surrogates

Aromatic amination

Aromatic amines

Aromatic amines reaction with nitrous acid

Aromatic amines reaction with, phosgene

Aromatic amines reactions with carbonate radical

Aromatic amines reactions with hydroxyl radical

Aromatic amines reactions with hypochlorite

Aromatic amines reactions with ozone

Aromatic amines with acetophenone

Aromatic amines with picric acid

Aromatics amination

Assay of Aromatic Amines by HPLC with Electrochemical Detection

Carbonates reaction with aromatic amines

Glucose condensation with aromatic amines

Hydroamination with aromatic amines

Polymers with aromatic amine groups

Reaction with aromatic amines

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