P-Naphthylamine

CA UTION. This compound has carcinogenic properties and great care should be taken to avoid all contact with it during its isolation and drying. 

2-p-Tolylamino-5-hydroxynaphthalene-7-sulphonic acid. Reflux a mixture of 108 g. of pure p-toluidine, 108 g. of J acid (2-amino-5-hydroxynaphthalene-7-sulphonic acid), 84 g. of sodium bisulphite and 250 ml. of water for 30 hours in a 1500 ml. three-necked flask, equipped with a reflux condenser and mechanical stirrer. Add sodium carbonate until the mixture is alkaline and remove the excess ofp-toluidine by steam distillation. Keep the residual solution in a refrigerator until crystallisation is complete, filter with suction on a Buchner funnel, and wash with 25 ml. of saturated sodium chloride solution. Dissolve the product in ca. 350 ml. of hot water to which sufficient hydrochloric acid is added to render the mixture acid to Congo red. Keep in a refrigerator until crystallisation is complete, filter with suction, wash with a little ice-cold hydrochloric acid, followed by a small volume of ice-cold water. Dry the residual 2-p-tolylamino 6-hydroxynaphthalene-7-sulphonic acid at 100° the jdeld is 96 g. 

Benzyl phthalimide. Grind together 53 g. of finely-powdered, anhydrous potassium carbonate and 147 g. of phthalimide (Section IV,169) in a glass mortar, transfer the mixture to a 750 ml. round-bottomed flask, and treat it with 252 g. (230 ml.) of redistilled benzyl chloride. Heat in an oil bath at 190° under a reflux condenser for 3 hours. Whilst the mixture is still hot, remove the excess of benzyl chloride by steam distillation. The benzyl phthalimide commences to crystallise near the end of the steam distillation. At this point, cool the mixture rapidly with vigorous stirring so that the solid is obtained in a fine state of division. Filter the solid with suction on a Buchner funnel, wash well with water and drain as completely as possible then wash once with 200 ml. of 60 per cent, ethanol and drain again. The yield of crude product, m.p. 100-110°, is 180 g. Recrystallise from glacial acetic acid to obtain pure benzyl phthalimide, m.p. 116° the recovery is about 80 per cent. 

Benzylamine. Warm an alcoholic suspension of 118-5 g. of finely-powdered benzyl phthalimide with 25 g. of 100 per cent, hydrazine hydrate (CAUTION corrosive liquid) a white, gelatinous precipitate is produced rapidly. Decompose the latter (when its formation appears complete) by heating with excess of hydrochloric acid on a steam bath. Collect the phthalyl hydrazide which separates by suction filtration, and wash it with a little water. Concentrate the filtrate by distillation to remove alcohol, cool, filter from the small amount of precipitated phthalyl hydrazide, render alkaline with excess of sodium hydroxide solution, and extract the liberated benzylamine with ether. Dry the ethereal solution with potassium hydroxide pellets, remove the solvent (compare Fig. //, 13, 4) on a water bath and finally distil the residue. Collect the benzylamine at 185-187° the yield is 50 g. 

P-Phenylethylamine. Prepare P phenylethyl phthalimide as above by substituting p-phenylethyl bromide (Section 111,37) for benzyl 

Other Names 2-Naphthylamine P-Aminonaphthalene 3-Naphthylamine 2-Aminonaphthalene  

37270 Fast Scarlet Base B Naphthaleti-2-ylamine o-Aminonaphthalene CA Index Name 2-Naphthalenamme CAS Registry Number 91-59-8 Merck Index Number 6399 Chemical Structure 

Chemical/Dye Class Huorescent Molecular Formula C10H9N Molecular Weight 143.19 pH Range 2.8—4.4 

Physical Form White to reddish crystals Solubility Soluble in hot water, ethanol, ether Melting Point 111—113°C Boiling Point 306°C Synthesis Synthetic methodsi  

Major Applications Microelectronics,5 power transmission fluid, insulators for electronicdevices, photoresists,8 display device, imaging process,semiconductors, diesel fuel additives, 12 battery,i3 adhesive,w paints,is inks,i chalk,ii leather,is textiles,is dye synthesis,i5soil products Safety/Toxicity Carcinogenicity i. cytotoxicity, 3 genotoxicity,23 mutagenicity,24 tumorigenicity s 

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The amlnation reaction is reversible thus P-naphthylamine can be reconverted into p-naphthol by heating with aqueous sodium bisulphite solution, then adding alkali and boiling until all the ammonia is expelled. 

Thus good yields (> 60 per cent) are obtained with aniline and methyl, ethyl, n-propyl and n-butyl phosphates with a- and P-naphthylamine and methyl or ethyl phosphate nuclear substituted anilines and methyl or ethyl phosphate. 

Methylaniline Ethylaniline n-Propylaniline n-Butylaniline Benzylaniline 2 -MethyIbenzylamine N-Ethylbenzylamine 2 -Methyl o-toluidine N-Methyl m-toluidine 2 -MethyI p-toluidine N-Ethyl o-toIuidine N-Ethyl m-toIuidine 2S -Ethyl p-toluidine 2 -MethyI a-naphthylamine N-Methyl p-naphthylamine N-Phenyl- a-naphthylamine 2 -Phenyl-P-naphthylamine... 

Acetyl-o-aniaidine Acetyl-m-anisidine Acetyl-p-anisldine Acetyl-o-phenetidine Acetyl-m-phenetidine Acetyl-p-phenetidine (or phenacetin) Acetyl-a-naph thy lam ine Acetyl- p-naphthylamine... 

Solubility in 5 per cent, hydrochloric acid. Add the acid to 0 10 g. of the solid or 0 20 ml. of the liquid in quantities of 1 0 ml. until 3 0 ml. have been introduced. Some organic bases (e.g., p-naphthylamine) form hydrochlorides that are soluble in water but are precipitated by an excess of acid if solution occurs at any time, the unknown is assigned to Group IV. If the compound appears insoluble, remove some of the supernatant liquid by means of a dropper to a semimicro test-tube (75 X 10 mm.), and add 5 per cent, sodium hydroxide solution until basic and observe whether any precipitate is produced the formation of a precipitate will place the compound in Group IV. 

Phenylnaphthylamines W-Phenyl-p-naphthylamine (11) Yes Once widely used in rubber industry because of good all-round effect in diene rubbers. Now almost obsolete. 

Carcinogens Cancer-producing agents Skin Respiratory Bladder/urinary tract Liver Nasal Bone marrow Coal tar pitch dust crude anthracene dust mineral oil mist arsenic. Asbestos polycyclic aromatic hydrocarbons nickel ore arsenic bis-(chloromethyl) ether mustard gas. p-naphthylamine benzidine 4-am i nodi pheny lam ine. Vinyl chloride monomer. Mustard gas nickel ore. Benzene. 

Heating arylamines with carbon dioxide at 200 C (8500 atm) gives good yields of 3-aryl derivatives of 2,4-dihydroxyquinazoline ° (see 5e). The method is unsatisfactory when riitro, halo, and phenolic anilines and a- or p-naphthylamines are used. 

A convenient synthesis of benzo[g]quinoline via the condensation of P-naphthylamine with malondialdehyde followed by cyclization in pol5q>hosphoric acid was reported <95H(41)2221>. 

P-Nitronaphthalene is not formed by direct nitration. For the preparation of p-naphthylamine, the Bucherer reaction may be applied to p-naphthol, i.e., by heating with ammoniacal ammonium sulphite solution at 150° (under pressure). The reaction involves the addition of the bisulphite to the keto form of p-naphthol ... 

P-Bromonaphthalene. The preparation from p-naphthylamine, which has carcinogenic properties, is avoided by the use of 2-naphthylamine-1-sulphonic acid ( 2-amino-1-naphthalenesulphonic acid ) the latter is obtained commercially by cautious treatment of p-naphthol with sulphuric acid—the SOjH group first enters the 1-position—followed by the Bucherer reaction. Diazotisation and reaction with cuprous bromide yields 2-bromonaphthalene-l-sulphonic acid heating with sulphuric acid eliminates the sulphonic acid group to give 2-bromonaphthalene. 

Ethy Ibenzy lamine A -Methyl o-toluidine A -Methyl m-toluidine. 2V-Methyl p-toluidine A -Ethyl o-toluidine -Ethyl m-toluidine -Ethyl p-toluidine 2V-Methyl a-naphthylamine 2V-Methyl p-naphthylamine 2V-Phenyl- a-naphthylamine N-Phenyl- p-naphthylamine... 

The substance may be obtained from p-naphthylamine (Section IV,38) by the procedure described imder p Tolunitrile (Section IV,66). 

One of the earliest organic antioxidants, now obsolescent due to its severe staining properties, health problems, and to the production of more effective antioxidants. Phenyl-p-Naphthylamine... 

Historically, bladder tumors have been associated with exposures in the aniline dye industry. However, conclusive evidence for any one particular exposure could not be obtained in these studies since the workers were exposed to many chemicals within the same work area. For example, Case et al. (1954) investigated the incidence of bladder tumors among British workers in the chemical dye industry. In addition to aniline, the workers were exposed to other aromatic amines, including a- and P-naphthylamine, benzidine, and auramine. Although exposures could not be quantified, there was insufficient evidence to suggest that aniline was a cause of bladder cancers. More recent studies indicate that P-naphthylamine, 4-aminodiphenyl, 4-nitrodiphenyl, 4,4-diaminodiphenyl, or o-toluidine may be involved in increased cancers in the dye industry (Ward et al. 1991 Benya and Cornish 1994). 

Use Rat poison. Banned in Britain due to carcinogenic impurities such as p-naphthylamine (Cremlyn, 1991). 

Naphthol-TV-methylcarbamate, see Carbaryl 6-Naphthylamine, see 2-Naphthylamine a-Naphthylamine, see l-Naphthylamine alpha-Naphthylamine, see l-Naphthylamine p-Naphthylamine, see 2-Naphthylamine... 

Transformation of P-naphthols to P-naphthylamines using ammonium sulfite. 

ANTU was not carcinogenic in rodent feeding studies. Cases of bladder tumors among rat catchers exposed to ANTU have been attributed to P-naphthylamine, a manufacturing impurity of ANTU. In bacterial assays ANTU induced mutations. 

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