Nitroso amines benzene

There is no reference to the formation of the ortho nitroso amine in the benzene series, indeed the formation and characterisation of ortho nitroso amines from any reaction has only been reported once or twice79. When the para position is blocked by a substituent, de-nitrosation so the secondary amine can occur80 a certain amount (which depends on the conditions) of denitrosation occurs also, concurrently with the rearrangement81, so that N-nitroso-N-methylaniline (XLVII) yields N-methylaniline (XLVIII) as well as the rearrangement product p-nitroso-N-methylaniline XLIX, viz. 

Nitroso Benzene.—The nitroso or nitrous acid derivatives are exactly analogous to the nitro or nitric acid derivatives. As the nitro radical is (AO2), so the nitroso radical is NO) and whenever this radical is present, as we found in the nitroso-amines (p. 61), and as we shall find in some more complex compounds of the dye class, it means nitroso derivative. The simplest representative, viz., nitroso benzene, CeHs—NO, differs from nitro benzene in that it is not formed by the direct action of the acid on the hydrocarbon nor, as shown above, is it able to be isolated as a reduction product of nitro benzene. It is prepared, however, by the oxidation of phenyl hydroxyl amine, either by means of ferric chloride, FeCU, or of chromic acid, CrOa. 

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... 

Secondary Amines.— Like secondary amines the hydrazo compounds contain the (NH) group and toward nitrous acid hydrazo benzene reacts at low temperatures in the manner characteristic of this class of amines (p. 61) and yields a double nitroso amine compound. 

Blangey314 obtained direct C-nitration of some primary amines when he added the amine to an ice-cold solution of sodium nitrite in concentrated sulfuric acid with exclusion of moisture. After complete consumption of the nitrous acid the products were precipitated by ice-water and proved in each case to be the / -nitroso amine. Thus were obtained the 4-nitroso derivatives of 1-naphthylamine and its 2-, 6-, 7-, and 8-monosulfonic acids, and in the benzene series those of m-anisidine, m-toluidine (NH2 = 1), etc. The sulfo group was split off from naphthionic acid, which gave a good yield of the product obtained from 1-naphthylamine. For the preparation of C-nitroso derivatives of primary amines from nitrosophenols see page 529. 

Several reports have appeared on the reactions of nitroso-amines. N-nitrosodibenzylamine (166) reacts with phenacyl bromide in the presence of silver hexafluoroantimonate to give the iV-nitrene (167), which in ether as solvent results in bibenzyl and (168), while the major product in benzene is diphenyl-methane. 

Reactions with Organic Compounds. Tetrafluoroethylene and OF2 react spontaneously to form C2F and COF2. Ethylene and OF2 may react explosively, but under controlled conditions monofluoroethane and 1,2-difluoroethane can be recovered (33). Benzene is oxidized to quinone and hydroquinone by OF2. Methanol and ethanol are oxidized at room temperature (4). Organic amines are extensively degraded by OF2 at room temperature, but primary aHphatic amines in a fluorocarbon solvent at —42°C are smoothly oxidized to the corresponding nitroso compounds (34). 

The nitroso-group in the p-position has a remarkable influence in making possible the hydrolytic removal of the dimethylamino group from the benzene ring. The reaction is used technically for the preparation of secondary amines. (Trimethylamine is obtained by heating ammonium chloride with formaldehyde.)... 

Nitro compounds in presence of carbonyl group are selectively reduced to amines in the presence of Raney nickel catalyst. Hydrazine reduces nitrdes yielding hydrazones. Under controlled reaction conditions other functional groups, including nitroso and oxime, may be reduced. Many partially hydrogenated derivatives, such as azo-, hydrazo-, and azoxy compounds may be obtained by partial reduction with hydrazine. Reaction with chlorobenzene yields benzene. 

While the condensation of amines with nitroso compounds appears to have wide applicability in the benzene series, it seems to lead to complex dye molecules in the naphthalene series. A method has been developed using a somewhat complex reaction between thionylamines and substituted hydroxylamines which does produce azo compounds derived from naphthalenes. This synthesis is of particular interest because it helped to settle the question whether true naphthylazo compounds with hydroxyl groups could exist [36]. 

In the oxidation of pentafluoroaniline with performic acid, along with the expected pentafluoronitrosobenzene, a 17% yield of decafluoroazoxy-benzene was isolated. Separate experiments showed that the condensation of the nitrosobenzene with the residual amine did not lead to the clean-cut preparation of the azoxy compound, whereas the thermal degradation of the nitroso compound did afford the azoxy compound. The implications of these observations are that either the azoxy product was formed, at least in part, by direct oxidation of the amine or the thermal history of the reaction permitted its formation from the intermediate nitroso compound [29]. 

A considerable number of acylarylamines, among them o-chloroacet-anilide, 2,6-dichloro-4-nitroacetanilide, and l-acetamido-2-methylan-thraquinone, form abnormal nitroso compounds with nitrous fumes others, such as 4-dimethylamino-4 -acetamidoazobenzene, benzene-p-toluidide, and diacetyl-1,3-phenylene diamine, do not yield nitroso compounds with nitrous fumes a third group, which includes p-nitroacet-anilide and a- and /3-acetamidoanthraquinone, is recovered unchanged after the same treatment.63 In general, the acetamido group submits to nitrosation, whereas the benzoyl and benzenesulfonyl and toluenesul-fonyl derivatives of amines are resistant to the notion of nitrous fumes. 

SYNS ACCELERINE p-piMETHYLAMINO)-NITROSOBENZENE 4-piMETHYLAMINO)NITROSO-BENZENE DIMETHYL-p-NITROSOANILINE pOT) N,N-DIMETHYI 4-NITROSOBENZENAMINE DIMETHYL(p-NITROSOPHENYL)AMINE NCI-C01821 NDMA p-NITROSO-NJ -DIMETHYLANIUNE 4-NITROSODIMETHYLANIUNE p-NTTROSODIMETH-YLANILINE pOT) PARANITROSODIMETHYL-ANILIDE ULTRA BRHilANT BLUE P... 

Nitroso-benzene. —Intermediate between nitro benzene and phenyl hydroxyl amine is the nitrous acid derivative or nitroso benzene. This compound can not be formed by reduction of the nitro benzene, but is obtained by oxidizing phenyl hydroxylamine. 

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)-... 

Di-phenyl Azo benzene Phenyl nitro amine Nitroso benzene Nitro benzene... 

By far the most stable nitroso compounds are those of the aromatic series. The smoothest C-nitrosation is achieved with phenols and tertiary amines having a free para-position. In benzene derivatives the nitroso group enters almost exclusively284 the para-position to the hydroxyl or amino group. In the naphthalene series the reaction is not always unidirectional 1-nitroso-2-naphthol is obtained almost quantitatively from 2-naphthol,285 but 1-naph-thol gives a mixture of about equal parts of 2- and 4-nitroso-l-naphthol.286... 

Hansson and Alm [10] have separated diphenylamine, triphenyl-amine and the corresponding nitroso- and nitro derivatives on silica gel 6 layers, using toluene, benzene or chloroform. 

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