8-Naphthylamine

CAUl lON. 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-sulphonio 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-5-hydroxynaphthalene-7-sulphonic acid at 100° the yield is 95 g. 

Benzylatnine. 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 3ueld is 50 g. 

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

Reduction of A-nitrosomethylaniline. Into a 1 litre round-bottomed flask, fitted with a reflux condenser, place 39 g. of A-nitroso-methylaniline and 75 g. of granulated tin. Add 150 ml. of concentrated hydrochloric acid in portions of 25 ml. (compare Section IV.34) do not add the second portion until the vigorous action produced by the previous portion has subsided, etc. Heat the reaction mixture on a water bath for 45 minutes, and allow to cool. Add cautiously a solution of 135 g. of sodium hydroxide in 175 ml. of water, and steam distil (see Fig. II, 40, 1) collect about 500 ml. of distillate. Saturate the solution with salt, separate the organic layer, extract the aqueous layer with 50 ml. of ether and combine the extract with the organic layer. Dry with anhydrous potassium carbonate, remove the ether on a water bath (compare Fig. II, 13, 4), and distil the residual liquid using an air bath (Fig. II, 5, 3). Collect the pure methylaniline at 193-194° as a colourless liquid. The yield is 23 g. 

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- 

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 distiUation. 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. Reorystallise from glacial acetic acid to obtain pure benzyl phthalimide, m.p. 116° the recovery is about 80 per cent. 

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Fluoronaphthalene [321-38-0] is prepared from 1-naphthylamine by the Balz-Schiemaim reaction in 52% yield or by diazotization in anhydrous hydrogen fluoride in 82% yield. Electrophilic substitution occurs at the 4-position, eg, nitration with fuming nitric acid in acetic acid gave 88% yield of l-fluoro-4-nitro-naphthalene [341 -92-4]. 

Miscellaneous uses include several organic compounds and intermediates, eg, 1-naphthalenol, 1-naphthylamine [134-32-7] 1,2,3,4-tetrahydronaphthalene, decahydronaphthalene, and chlorinated naphthalenes. 

Naphthaleneamine. 1-Naphthylamine or a-naphth5iamine/7i5 -i2- can be made from 1-nitronaphthalene by reduction with iron—dilute HCl, or by catalytic hydrogenation it is purified by distillation and the content of 2-naphthylamine can be reduced as low as 8—10 ppm. Electroreduction of 1-nitronaphthalene to 1-naphthylamine using titania—titanium composite electrode has been described (43). Photoinduced reduction of 1-nitronaphthalene on semiconductor (eg, anatase) particles produces 1-naphthylamine in 77% yield (44). 1-Naphthylamine/7J4-J2-. can also be prepared by treating 1-naphthol with NH in the presence of a catalyst at elevated temperature. The sanitary working conditions are improved by gas-phase reaction at... 

Naphthaleneamine is a dye intermediate and is used as the starting material in the manufacture of the rodenticide, Antii (8), l-naphthalenethiourea/5 %< < -4/, which is prepared by heating a mixture of 1-naphthylamine hydrochloride, NH SCN, and a large amount water for 14—16 h while keeping its volume constant by a dding an additional amount of water, to give a 97% yield. Its LD q is 600 mg in squirrels (46). 

Pigment Blue 1 [1325-87-7] 42595 2 triarylcarbonium PTMA salt (Victoria Blue B) condensation of 4,4 -bis-A/A/-dimethyl aminoben2ophenone with /V-ethyl-1-naphthylamine, followed by oxidation and salt formation... 

Benzoquinolines. Because certaia alkaloids are characterized by these more elaborate fused-riag systems, their syathesis has beea reviewed ia detail (138). Heatiag 4-methoxy-1-naphthylamine with epichlorohydrin produces a modest yield of... 

Technologically, the most important examples of such couplers are 1-naphthylamine, 1-naphthol, and sulfonic acid derivatives of 1-naphthol (Fig. 2). Of great importance in the dyestuff industry are derivatives of l-naphthol-3-sulfonic acid, such as H-acid (8-amino-l-naphthol-3,6-disulfonic acid [90-20-0])... 

Nitro-l-diazo-2-naphthol-4-sulfonic acid prefers the 2-position in spite of the nitro group, and increasing alkalinity favors ortho coupling with diazophenols. 1-Naphthalenesulfamic acid [24344-19-2] (ArNHSO H) and N-nitro-1-naphthylamine [4323-69-7] (ArNHNO ) couple exclusively in the para position. The substitution of resorcinol [108-46-3] and y -phenylenediamine [108-45-2] is compHcated and has been discussed (29,30). The first azo dyes from aniline, eg. Aniline Yellow [60-09-3] (19) (Cl Solvent Yellow 1 Cl 11000) were manufactured in 1861 and Bismark Brown [10114-58-6] (20) (Cl Basic Brown 1 Cl 21000) appeared in 1863. The reaction is as follows ... 

Other disazo dyes with good substantivity and high wet-fastness properties on polyamides are Acid Red 114 (40), made by coupling o-toHdine to phenol which is then coupled to G-acid, followed by reaction of the phenoHc hydroxyl group with -toluenesulfonyl chloride, and Acid Blue 113 (41) (metanilic acid — 1-naphthylamine — 8-anilino-1-naphthalenesulfonic acid). 

Bake sulfonation is an important variant of the normal sulfonation procedure. The reaction is restricted to aromatic amines, the sulfate salts of which ate prepared and heated (dry) at a temperature of approximately 200°C in vacuo. The sulfonic acid group migrates to the ortho or para positions of the amine to give a mixture of orthanilic acid [88-21-1] and sulfanilic acid [121 -57-3] respectively. This tendency is also apparent in polynuclear systems so that 1-naphthylamine gives 1-naphthy1amine-4-su1fonic acid. 

Naphthylamine [134-32-7] M 143.2, m 50.8-51.2 , b 160 , pK 3.94. Sublimed at 120° in a stream of nitrogen, then crystd from pet ether (b 60-80°), or abs EtOH then diethyl ether. Dried under vacuum in an Abderhalden pistol. Has also been purified by crystn of its hydrochloride from water, followed by liberation of the free base and distn finally purified by zone melting. CARCINOGEN. 

Naphthylamine hydrochloride [552-46-5] M 179.7, m sublimes on heating. Crystd from water (charcoal). 

Dinitronaphthalene ( Gamma-dinitronaph-thalene, 1,3-DNN), Bright yel needles from aq pyridine, mp 144°, bp subl (Refs 1 32) CA Registry No 606-37-1. It is prepd by the action of nitric ac/sulfuric ac on naphthalene at low temps (Refs 14 33) by the nitration of 1-MNN with a mixt of 17.3% nitric ac, 61.2% sulfuric ac, and 21.5% w, temp 59-75°, time 90min (Ref 52) by the action of powd Cu (Ref 18) or hydrazine (Ref 22) on l-chioro-2,4-dinitro-naphthalene by the diazotization of 2,4-dinitro-1-naphthylamine followed by redn of the dia-zonium salt with EtOH (Ref 25) or by the action of Br on 5,7-dinitro-l,2,3,4-tetrahydro-naphthalene followed by dehydrobromination (Ref 13). It is used to prep more highly nitrated naphthalenes... 

If relatively basic and nucleophilic aromatic amines are diazotized in nitrosylsul-furic acid, C- instead of TV-nitrosation takes place as shown by Blangey (1938) for 1-naphthylamine, which gave in this system 4-nitroso-l-naphthylamine. A possible mechanistic explanation of Blangey s observation is given in Section 3.2. 

Table 3-1. Equilibrium constants Kxno (Scheme 3-28) and rate constants for diazotization of aniline (Ar2, Scheme 3-29) and of 1-naphthylamine (k2 and k-2/k Scheme 3-34) in water by nitrosyl chloride, nitrosyl bromide, nitrosyl thiocyanate, S-nitrosothiuronium ion [(NH2)2CSNO], and dinitrogen trioxide at 25 °C.

For substituted anilines (Thompson and Williams, 1977) and for 1-naphthylamine and a series of derivatives thereof (Castro et al., 1986a), k2 and the ratio Ar 2/Ar3 have been determined for nucleophilic catalysis with Cl-, Br-, SCN-, and SC(NH2)2. The values of k2 correspond fairly well to those found for the diazotization of aniline, but those of Ar 2/Ar3 increase markedly in the above sequence (Table 3-1). As k3 is expected to be independent of the presence of Cl- or Br- and to show little dependence on that of SCN- or thiourea, the increase in k 2/k3 for this series must be due mainly to 2. Indeed, the value of log(Ar 2/Ar3) shows a linear correlation with Pearson s nucleophilicity parameter n (Pearson et al., 1968). This parameter is based on nucleophilic substitution of iodine (as I-) in methyl iodide by various nucleophiles. The three investigations on nucleophilic catalysis of diazotization demonstrate that Pearson s criteria for bimolecular nucleophilic substitution at sp3 carbon atoms are also applicable to substitution at nitrogen atoms. 

Boldyrev and Grivnak (1984) reported that 4-nitrobenzenediazothiosulfonic acid adducts (4-N02 — C6H4 — N2 — S — S02 — Ar ), which were obtained by reaction of 4-nitrobenzenediazonium salts with benzene- and 4-toluenethiosulfonic acid salts (Ar — S02 — S K+), form azo compounds with 2-naphthol and 1-naphthylamine-4-sulfonic acid. 

Structure 12.148 was already supported by results from Stamm and Zollinger s investigation (1957) in which activation entropies were determined. The mechanism was corroborated by further activation entropy studies (Demian, 1972, 1973 Demian et al., 1983) and investigations on the 2/4-ratio of coupling of 1-naphthylamine carried out by Hashida et al. (1975 b). 

If the coupling component is not ionic, however, more dramatic effects occur, as found by Hashida et al. (1979) and by Tentorio et al. (1985). Hashida used N,N-bis(2-hydroxyethyl)aniline, while Tentorio and coworkers took 1-naphthylamine and l-amino-2-methylnaphthalene as coupling components. With cationic arenediazo-nium salts and addition of sodium dodecyl sulfate (SDS), rate increases up to 1100-fold were measured in cases where the surfactant concentration was higher than the critical micelle concentration (cmc). Under the same conditions the reaction... 

In a more recent paper (Stovpovoi et al., 1991b) Bagal and coworkers interpret their observation that Arrhenius plots of the rates of various N- and C-couplings of aromatic amines (e. g., 1-naphthylamine, 2,6-naphthylaminesulfonic acid, and 4-me-thylaniline) are linear only in aqueous systems, but not in aprotic solvents such as nitromethane or acetonitrile. Their explanation is based on an extension of the clas-... 

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