Amine derivatives, from aromatic

As for the amine moiety, the rearrangement has been demonstrated (although not unequivocally in all cases) for mono-A -substituted glycosyl-amines derived from aromatic amines and aralkyl- and alkyl-amines and for di-A-substituted glycosylamines containing dialkyl, alkyl-aryl, aralkyl, isocyclic, and heterocyclic alkyl radicals. The rearrangement has been reported for A-glucosyl derivatives of amino acids, but not as yet... 

A number of amines derived from aromatic amino acid are present in brain in trace quantities. Since aromatic L-amino acid decarboxylase shows a broad substrate specificity, it is not surprising that compounds such as tyramine, tryptamine, phenylethylamine, and histamine are present in brain. These amines are derived from the simple decarboxylation of the corresponding... 

The occurrence and significance of some biogenic amines are listed in Table XII. The biogenic amines derived from aromatic amino acids are of both pharmacologic and physiological interest. They will be discussed in Chapt. XX, because of their close relationship to hormones. 

Use has been made of the C-N cleavage in the conversion of the bicyclic tertiary amines, derived from the 4tc + 2tc cycloaddition of pyrroles and isoindoles with benzynes, into aromatic systems, e.g. naphthalen-l,4-imines and anthracen-9,10-imines yield naphthalenes and anthracenes with the extrusion of the nitrogen bridge [24] in yields which are higher than those obtained by standard oxidation procedures. 

In the following sections, we discuss compounds whose amide group is adjacent to an aromatic system. A distinction is made between aromatic amides derived from aromatic acids (e.g., benzamides) or from aromatic amines (e.g., anilides). The discussion will be completed with compounds in which the amide bond links two aromatic systems. 

Reduction of amides to aldehydes was accomplished mainly by complex hydrides. Not every amide is suitable for reduction to aldehyde. Good yields were obtained only with some tertiary amides and lithium aluminum hydride, lithium triethoxyaluminohydride or sodium bis 2-methoxyethoxy)aluminum hydride. The nature of the substituents on nitrogen plays a key role. Amides derived from aromatic amines such as JV-methylaniline [1103] and especially pyrrole, indole and carbazole were found most suitable for the preparation of aldehydes. By adding 0.25 mol of lithium aluminum hydride in ether to 1 mol of the amide in ethereal solution cooled to —10° to —15°, 37-60% yields of benzaldehyde were obtained from the benzoyl derivatives of the above heterocycles [1104] and 68% yield from N-methylbenzanilide [1103]. Similarly 4,4,4-trifluorobutanol was prepared in 83% yield by reduction of N-(4,4,4-trifluorobutanoyl)carbazole in ether at —10° [1105]. 

In contrast to the epoxides, preparative routes to the aziridines are fairly evenly split between the [C=N + C] and the [C=C + N] routes. Among contributions in the former category, aziridine carboxylate derivatives 110 can be prepared through the lanthanide-catalyzed reaction of imines with diazo compounds, such as ethyl diazoacetate (EDA). In this protocol, iV-benzyl aryl aldimines and imines derived from aromatic amines and hindered aliphatic aldehydes are appropriate substrates <99T12929>. An intramolecular variant of this reaction (e.g.. Ill —> 112) has also been reported <990L667>. 

As might be expected, the stability and reactivity of diazonium salts are affected by substituents as well as by the anion. The rate of coupling and the location of the azo bond are influenced by substituents on the coupling reagent. Some primary and secondary aromatic amines derived from benzene initially form A-azo compounds, which rearrange to p-aminoazo compounds in acidic media [8b, c]. Tertiary amines, on the other hand, behave normally. Preparation 2-3, while of a rather complex molecule, illustrates the simple techniques commonly used in coupling in an aqueous system. Note the presumed preferential tendency of coupling to take place predominantly in the para position. 

The nucleophilic addition of organometallic reagents to imines provides an attractive route to amines [4]. Recendy, however, some completely different approaches to the synthesis of a-aryl amine were reported. Hayashi and Ishigeda-ni found a new catalytic system for the asymmetric addition of arylstannanes to imines derived from aromatic aldehydes (Scheme 11) [20]. 

Kiese, M. (1966). The biochemical production of ferrihemoglobin-forming derivatives from aromatic amines, and mechanisms of ferrihemoglobin formation. Pharmacol. Rev. 18 1091-1161. 

A catalytic asymmetric amination of enecarbamates has been attained using a chiral Cu(II) complex of diamine (210) as catalyst. Thus, azodicarboxylates have been shown to react with various enecarbamates (208) derived from aromatic and aliphatic ketones and aldehydes to provide acylimines (209) in good yields with high enantioselectivity (<99% ee). The catalyst loading required for high enantioselectivity was generally low (0.2 mol% in some cases).259... 

Monoazo dyes derived from aromatic amines as coupling components and carbo-cyclt aromatic amines as diazo components are the class of disperse azo dyes with the greatest economic importance. Commercial products are most often represented by structure 2, in which 4-nitroaniline [100-01-6] and its substituted derivatives constitute the diazo component. 

The rearrangement products derived from aromatic and non-aromatic heterocyclic amines crystallize readily from the lower alcohols. Unlike those of many of the A-substituted glycosylamines, the crystals are not solvated. On the other hand, the ketose derivatives of aralkyl- and alkyl-amines, such as 2-phenylethylamine, ethanolamine, diethanolamine, glycine ethyl ester, and phenylalanine (see Table II), are hydrated or alcoholated, or both, and are difficult to isolate in pure crystalline form. The crystals which have been isolated were hygroscopic. Alcohols, aqueous alcohols, and water are the most commonly used solvents for crystallization. Acetone, ether, or benzene have been added to the alcoholic media in order to increase the yield of crystalline compound. The use of solvents that contain peroxides promotes decomposition of the crystals during storage. ... 

Amidines of aliphatic acids are generally not reducible in buffered solution. Some amidines derived from aromatic acids are reducible at very negative potentials and only in a narrow pH interval from slightly acid to alkaline solution. The reduction is similar to that of imidic esters [Eq. (10)], and yields the amine [44]. 

Short-lived free radicals derived from aromatic amines can be generated and detected by the ETSF method. Long-lived free radicals in solution, such as tris(4-bromophenyl)amine radical cation (129), react with aromatic amines to yield short-lived radical anions (130a-d), as shown in equation 20. Solutions of 129 are generated electrolytically and... 

Activators and vulcanizing agents, including accelerators, mainly derived from aromatic amines, account for around half the consumption of organic rubber-processing chemicals. 

A group of Italian workers has claimed that 1,3-disubstituted-2-methyl-5-oxo-3-pyrazolin-4-carboxaldehydes can be prepared through methylation of the Schiff bases derived from aromatic amines and l,3-disubstituted-2-pyrazolin-5-ones.1097 The methylation is carried out with methyl iodide which methylates the ring at N-2, and this is followed by hydrolysis of the Schiff bases with alkaline solutions (eq. 221). Passerini and Losco1092,1093-1097 and Ridi1181 claimed to have... 

Mannich bases formed from formaldehyde, secondary amines and ort/io-derivatives of phenol and Schiff bases derived from aromatic ort/io-hydroxyaldehydes are treated as rather convenient model systems to study intramolecular proton transfer . 

Work carried out in our laboratories over the past three years and in conjunction with the research group of Daktemieks at Deakin University has been directed toward the development of novel enantiomerically pure stannanes for use in free-radical reduction chemistry. To that end Dunn prepared a series of menthyl-substituted stannanes 18 -20 and some others derived from aromatic amines (eg. 21, 22).Perchyonok tested these reagents against a series of substrates while Henry modelled the reactions in question through the use of ab initio molecular orbital theory. 

Association Frangaise de Normalisation (AFNOR) (2004a), EN 14362-1, Textiles. Methods for the determination of certain aromatic amines derived from azo colorants - Part 1 Detection of the use of certain azo colorants accessible without extraction, Paris, May. 

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