Nitroso amines anilines

Aromatic amines (anilines) may become activated in vivo to form reactive amines. These are nucleophiles and may attack DNA, forming covalent modifications. Aromatic nitro compounds can be metabolised to also form reactive amines. A-nitroso compounds result in the alkylation of oxygen sites in DNA bases (0-6 in guanine and 0-4 in thymidine) [8,10]. 

In diesem Zusammenhang ist bemerkenswert, daB mittels Nitroso-hydroxylaminsulfonat Alkohole und Amine (Anilin, Phenylhydrazin) sulfoniert werden konnen. Offensichtlich konnen in (41 b) anstelle von Wasser beliebige andere Basen treten. DaB die Zerfallsreaktion der Nitrosohydroxylaminsulfonate durchaus fiber normale untersalpetrige... 

Phenyl Nitroso Amine.—Under certain conditions aniline, a primary aromatic amine, apparently undergoes this same reaction and yields a nitroso amine. If the potassium salt of diazo benzene, which is obtained from aniline by the action of nitrous acid and which will be explained later (p. 591), is heated, a change takes place involving space relations. The product is isomeric with the diazo compound and is known as the... 

Nitrosamine and para Nitroso Methyl Aniline.—The reaction with nitrous acid is characteristic of secondary amines and yields phenyl methyl nitrosamine, the nitroso group entering the amino radical. This, however, undergoes rearrangement with the transference of the nitroso group to the ring yielding a nitroso benzene compound. 

The rearrangement occurs also when nitro benzene is electrolytically reduced by immersing the cathode in nitro benzene and sulphuric acid and the anode in sulphuric acid. Phenyl hydroxyl amine is first produced and by the above rearrangement is converted into para amino phenol. This rearrangement is analogous to the one occurring when phenyl methyl nitrosamine goes over to para-nitroso methyl aniline (P- S59)-... 

Rearrangement.—Like nitroso methyl aniline and phenyl hydroxyl amine it undergoes molecular rearrangement as above. 

Copper-catalyzed (stoichiometric or catalytic) at room temperature and weak base under air Wide scope of substrates alcohols, amides, amines, anilines, azides, hydantoins, hydrazines, imides, imines, nitroso, phenols, pyrazinones, pyridones, purines, pyrimidines, sulfonamides, sulfinates, sulfoximines, thiols, thiourea, ureas, and sulfonylguanidines... 

Arylation of a wide range of NH/OH/SH substrates by oxidative cross-coupling with boronic acids in the presence of catalytic cupric acetate and either triethyl-amine or pyridine at room temperature in air. The reaction works for amides, amines, anilines, azides, hydantoins, hydrazines, imides, imines, nitroso, pyrazi-nones, pyridones, purines, pyrimidines, sulfonamides, sulfinates, sulfoximines, ureas, alcohols, phenols, and thiols. It is also the mildest method for NIO-vinylation. The boronic acids can be replaced with siloxanes or starmanes. The mild condition of this reaction is an advantage over Buchwald-Hartwig s Pd-catalyzed cross-coupling. The Chan-Lam C-X bond cross-coupling reaction is complementary to Suzuki-Miyaura s C-C bond cross-coupling reaction. 

Photolysis of most substituted phenyl azides in hydrocarbons, as in the case of parent 47, leads to modest yields of identifiable products (azo-benzenes, nitro- and nitroso-benzenes, anilines etc.) along with polymeric tars or resins. Formation of azepines in the presence of primary and secondary amines is also typical of photolysis of the most substituted phenyl azides. In some cases, the products of formal bond insertion or... 

By condensing nitroso derivatives with primary amines. Nitrosobenzene and aniline, for example, readily give azobenzene. This method is seldom used... 

Secondary and tertiary amines are not generally prepared in the laboratory. On the technical scale methylaniline is prepared by heating a mixture of aniline hydrochloride (55 parts) and methyl alcohol (16 parts) at 120° in an autoclave. For dimethylaniline, aniline and methyl alcohol are mixed in the proportion of 80 78, 8 parts of concentrated sulphuric acid are added and the mixture heated in an autoclave at 230-235° and a pressure of 25-30 atmospheres. Ethyl- and diethyl-anihne are prepared similarly. One method of isolating pure methyl- or ethyl-aniline from the commercial product consists in converting it into the Y-nitroso derivative with nitrous acid, followed by reduction of the nitroso compound with tin and hydrochloric acid ... 

Nitroso compounds are formed selectively via the oxidation of a primary aromatic amine with Caro s acid [7722-86-3] (H2SO ) or Oxone (Du Pont trademark) monopersulfate compound (2KHSO KHSO K SO aniline black [13007-86-8] is obtained if the oxidation is carried out with salts of persulfiiric acid (31). Oxidation of aromatic amines to nitro compounds can be carried out with peroxytrifluoroacetic acid (32). Hydrogen peroxide with acetonitrile converts aniline in a methanol solution to azoxybenzene [495-48-7] (33), perborate in glacial acetic acid yields azobenzene [103-33-3] (34). 

The N,]S -dialkyl-/)-PDAs are manufactured by reductively alkylating -PDA with ketones. Alternatively, these compounds can be prepared from the ketone and -lutroaruline with catalytic hydrogenation. The /V-alkyl-/V-aryl- -PDAs are made by reductively alkylating -nitro-, -nitroso-, or /)-aminodipheny1 amine with ketones. The AijAT-dialkyl- PDAs are made by condensing various anilines with hydroquinone in the presence of an acid catalyst (see Amines-aromatic,phenylenediamines). 

As indicated above, tertiary aromatic amines are directly C-nitrosated. The usual reagents are sodium nitrite and dilute hydrochloric acid, sodium nitrite and glacial acetic acid containing concentrated hydrochloric acid, and nitrite esters with hydrochloric acid [21a, 27]. While tertiary amines with such complex alkyl groups as found in A,A-di(3,5,5-trimethylhexyl)aniline are readily nitrosated [25], of the four A-butyl-A-methylaniline isomers, JV-r-butyl-A-methylaniline does not undergo the reaction, and even the nitroso compounds which did form were only unstable oils [27]. 

As is well known, the oxidation of aniline with various oxidizing agents leads to a variety of products, usually highly colored polymeric materials. However, the reaction with Caro s acid (permonosulfuric acid, H2SOs) with aniline produces nitrosoaniline rapidly [76]. With this reagent, many aromatic amines have been oxidized to the corresponding nitroso compounds, e.g., the three nitronitrosobenzenes were prepared from the corresponding nitroani-lines [77, 78]. The reaction is normally carried out in an aqueous medium. In... 

In support of this view the p-amino-phenols themselves readily yield quinones. Also most p-substituted primary amines, e.g., p-diamines, p-alkylamines, such as p-toluidine, sulphanilic acid and its derivatives, behave similarly. In fact, the reaction can be used as a test for p-substi-tuted primary amines. p-Benzoquinone is usually made from aniline for the other p-quinones the p-amino-phenols, which are easily obtained by reduction of the p-nitroso-phenols and of azo-phenols, are employed. These reactions also apply, but not so widely, in the naphthalene series. 

Pinnow2-5,26-27 was the first to observe the interaction of the nitro group with a tertiary amino function. In a series of papers from 1895 onward he noticed that during the reduction of o-nitrodimethyl-anilines (68) with tin and hydrochloric acid, significant quantities of a 1-methylbenzimidazole (69) were formed together with the amine (70) and a chlorinated product (71). He proposed that the benzimidazole arose by reduction of the nitro to a nitroso group which then... 

Aromatic tertiary amines and phenolic compounds undergo nuclear nitro sation, as illustrated by the synthesis of p>nitrosodimethyl aniline (89%)i nitrosophenol (80%), and l-nitroso-2-naphthol (99%) In the reaction of a-naphthol, an isomeric mixture of the nitrosonaphthols is obtained. The nitrosation of phenols with nitrous acid usually produces p nitroso compounds however, o-nitiosophenols can be prepared by nitrosating phenols in the presence of cupric sulfate. ... 

Condensation of aromatic nitroso compounds with primary amines is a satisfactory procedure for obtaining azo compounds. An example is the combination of nitrosobenzene and aniline in acetic acid, which results in a quantitative yield of azobenzene. Similarly, a series of methyl-substituted azobenzenes have been prepared, although the yields are poor in the case of the oriAo-substituted compounds. As an illustration of the versatility of the reaction, nitrosobenzene can be condensed with o-methoxyaniline (o-anisidine)," p-aminobenzoic acid, o-phenylene-diamine monobenzoate, and m-nitroaniline to form the corresponding substituted azobenzenes. 

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