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Amines diphenylamine

The nitroso compound (diphenyinitrosamine) of the purely aromatic secondary amine diphenylamine is a crystalline solid, and therefore provides an interesting preparation eminently suitable for students ... [Pg.562]

TNT forms charge-transfer, or 7r, complexes with polycyclic aromatic hydrocarbons, aromatic amines, and aromatic nitro compds a number of these are listed below in Table 2. The complexes with three amines (diphenylamine, diethyl-aniline, p-anisidine) have characteristic colors this forms the basis for a rapid and convenient thin-layer chromatographic analytical procedure (Ref 34) for the identification of very small amounts of TNT. (For a discussion of the many color reactions of TNT, and of composite expls containing it, see Vol 3, C405-L ff)... [Pg.750]

Method. Dissolve the sample in 2M hydrochloric acid, and to 1 drop on a white tile add 1 drop of a 1% solution of sodium nitrite, and 1 drop of a 4% solution of 2-naphthol in 2M sodium hydroxide. Indications. A bright red or orange-red colour indicates the presence of a primary aromatic amine. Diphenylamine does not give a reaction amino-nitrothiazole (solid) gives a VIOLET colour. [Pg.132]

The nitrosamines are insoluble in water, and the lower members are liquid at ordinary temperatures. The separation of an oily liquid when an aqueous solution of an amine salt is treated with sodium nitrite is therefore strong evidence that the amine is secondary. Diphenylnitrosoamine is selected as a preparation because it is a crystalline substance and is thus easier to manipulate on a small scale than one of the lower liquid members. For this preparation, a fairly pure (and therefore almost colourless) sample of diphenyl-amine should be used. Technical diphenylamine, which is almost black in colour, should not be employed. [Pg.204]

Tertiary amines containing one alkyl and two aryl groups, such as mono-I ncthyldiphenyhiniir.e, Cl l3(C, l l.diX , arc rarely encountered and arc unimportant. They usually react with nitrous acid with the insertion of a nitroso group into only one of the two available para positions monomethyl-diphenylamine thus gives monomethyl-mono - pnitroso-diphenylamine. Cl hj(C.ill .)N C l 1 jXO, or V-nicthyl-p-nitrosodiphcnylaniine. [Pg.205]

A halogen atom directly attached to a benzene ring is usually unreactive, unless it is activated by the nature and position of certain other substituent groups. It has been show n by Ullmann, however, that halogen atoms normally of low reactivity will condense with aromatic amines in the presence of an alkali carbonate (to absorb the hydrogen halide formed) and a trace of copper powder or oxide to act as a catalyst. This reaction, known as the Ullmant Condensation, is frequently used to prepare substituted diphenylamines it is exemplified... [Pg.217]

B) Secondary amines, (i) Aromatic amines. Monomethyl and monoethylaniline, diphenylamine. (ii) Aliphatic and other amines. Diethyhmine, di-n-propylamine, di-isopropylamine. Also piperidine piperazine diethylene-diamine). [Pg.317]

Various basic substances, such as aromatic amines (naphthyl-amines dissolve with difficulty in dil. HCl, diphenylamine only in cone. HCl, triphenylamine insoluble) nitro-anilines some amino-carboxylic acids. [Pg.408]

Diphenylamine is a weak base, = 9 x lO ". Dilute acids are used to separate DPA from primary aromatic amines, such as aniline,... [Pg.242]

Acetone also reacts with diphenylamine, in the presence of acid, to form a variety of condition-dependent products (5). Excess amine and a small amount of strong acid catalyst at 100—150°C give 2,2-[4,4 -(dianilino)diphenyl]-propane [2980-26-9] (6). With a large amount of hydrochloric acid at 250°C in the presence of excess diphenylamine, the main product is 9,9-dimethylacridan [6267-02-3]. [Pg.243]

Retarders were originally arenecarboxylic acids. These acidic materials not only delay the onset of cross-linking but also slow the cross-linking reaction itself. The acidic retarders do not function weU in black-fiUed compounds because of the high pH of furnace blacks. Another type of retarder, A/-nitroso diphenylamine [86-30-6] was used for many years in black-fiUed compounds. This product disappeared when it was recognized that it trans-nitrosated volatile amines to give a several-fold increase in airborne nitrosamines. U.S. production peaked in 1974 at about 1.6 million kg. [Pg.226]

Aromatic Amines. Antioxidants derived from -phenylenediarnine and diphenylamine are highly effective peroxy radical scavengers. They are more effective than phenoHc antioxidants for the stabilization of easily oxidized organic materials, such as unsaturated elastomers. Because of their intense staining effect, derivatives of -phenylenediamine are used primarily for elastomers containing carbon black (qv). [Pg.225]

Dialkyl esters of 3,3 -thiodipropionic acid (53), cycHc phosphonites such as neopentylphenyl phosphite, derivatives of phosphaphenathrene-lO-oxide (54), secondary aromatic amines, eg, diphenylamine (55), and epoxidi2ed soybean oils (56) are effective stabili2ers for preventing discoloration of cellulose esters during thermal processing. [Pg.252]

Although in the dry state carbon tetrachloride may be stored indefinitely in contact with some metal surfaces, its decomposition upon contact with water or on heating in air makes it desirable, if not always necessary, to add a smaH quantity of stabHizer to the commercial product. A number of compounds have been claimed to be effective stabHizers for carbon tetrachloride, eg, alkyl cyanamides such as diethyl cyanamide (39), 0.34—1% diphenylamine (40), ethyl acetate to protect copper (41), up to 1% ethyl cyanide (42), fatty acid derivatives to protect aluminum (43), hexamethylenetetramine (44), resins and amines (45), thiocarbamide (46), and a ureide, ie, guanidine (47). [Pg.532]

Because nitrile rubber is an unsaturated copolymer it is sensitive to oxidative attack and addition of an antioxidant is necessary. The most common practice is to add an emulsion or dispersion of antioxidant or stabilizer to the latex before coagulation. This is sometimes done batchwise to the latex in the blend tank, and sometimes is added continuously to the latex as it is pumped toward further processing. PhenoHc, amine, and organic phosphite materials are used. Examples are di-Z fZ-butylcatechol, octylated diphenylamine, and tris(nonylphenyl) phosphite [26523-78-4]. All are meant to protect the product from oxidation during drying at elevated temperature and during storage until final use. Most mbber processors add additional antioxidant to their compounds when the NBR is mixed with fillers and curatives in order to extend the life of the final mbber part. [Pg.521]

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]

The dienone complex is an efiective phenylating agent for aromatic amines t.g., aniline and triearbonylcyclohexadienoneiron in glacial acetic acid at 75° overnight gives diphenylamine in 95% yield. ... [Pg.112]

Heating the sugar with strong acid yields furfural derivatives. Aldohexoses can eliminate water and formaldehyde under these conditions yielding furfural. This adehyde reacts with amines according to I to yield colored Schiff s bases. Ketohex-oses condense with diphenylamine in acid medium with simultaneous oxidation according to II to yield the condensation product shown. [Pg.180]

At the same, time attempts to apply this approach to the synthesis of phenotel-lurazine and its A-methyl derivative using diphenylamine and A-methyldiphenyl-amine as starting materials failed [83JOM(251)223 85KGS757]. The parent phe-notellurazine 35 (M = NH, R = R = H) has been prepared in low yield (7%) by refluxing an acetic acid solution of 4-trichlorotellurodiphenylamine 39 (89H1007). [Pg.16]

After standing about three hours, the diphenylamine hydrochloride is filtered and washed with benzene (Note 10). The benzene is distilled from the filtrate (Note n) and the residual triphenylamine is transferred to a 500-cc. modified Claisen flask (Org. Syn. 1, 40) and distilled under reduced pressure. The first fraction consists of some benzene, then the temperature rises rapidly and a few cubic centimeters of deeply colored distillate comes over just before the amine fraction, which is collected at i95-205°/io-i2 mm. The distillate is a yellow liquid which soon solidifies to a light yellow solid. The side arm of the distilling flask should be of rather large bore (about 10 mm.) to prevent clogging by the amine which solidifies. The crude product weighs 220-235 g. and melts at 120-124°. [Pg.117]

Vinyl Acetate CH3COOCH=CH2 OH compds, HCN, Halides, Halogens, Mer-cap tans, Amine, Silanes Oxygen Vap in Air 2.6 to 13.4% > Ambient > Ambient Inhibitor—Methyl Ether of Hydroquinone or 3-5ppm Diphenylamine. Store in a dry, cool place shield from light impurities 20.9-21.5 402 427 Free-radical polymerization initiated by Benzoyl Peroxide... [Pg.822]

Various Cu-exchanged zeolites have been examined in the nucleophilic substitution of bromo- and chlorobenzene towards aminated and oxygenated compounds (ref. 30). In amination a consecutive reaction to diphenylamine and reduction to benzene are the side-reactions (Fig. 10). [Pg.213]

Note This reagent sequence is a modiflcation of the reagent chlorine — potassium iodide — starch . Mobile phases containing ammonia must be removed completely before treatment with the reagent sequence, since otherwise the background will be colored too. Some secondary amines (e.g. diphenylamine) and some amides (e.g. 2,4-dinitrobenzamide) and methionine sulfoxide do not give reactions even in quantities of up to 1 to 2 (ig. [Pg.45]


See other pages where Amines diphenylamine is mentioned: [Pg.746]    [Pg.746]    [Pg.693]    [Pg.252]    [Pg.746]    [Pg.746]    [Pg.746]    [Pg.693]    [Pg.252]    [Pg.746]    [Pg.559]    [Pg.1048]    [Pg.232]    [Pg.233]    [Pg.544]    [Pg.534]    [Pg.643]    [Pg.382]    [Pg.908]    [Pg.142]    [Pg.383]    [Pg.1048]    [Pg.1221]    [Pg.228]    [Pg.370]   
See also in sourсe #XX -- [ Pg.262 ]




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