Naphthalenesulphonic acids

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. 

Reductive desulphonation of naphthalenesulphonic acids is also observed [84]. The 1-sulphonic acid substituent in a wide range of sulphonated naphthylamines is removed by reduction at mercury in aqueous sodium hydroxide [85], Reductive... 

In his experiments on the nitration of naphthalenesulphonic acid Lantz [85] found that the rate of nitration with a nitric acid and sulphuric acid mixture was highest when the concentration of sulphuric acid used was about 90% H2S04... 

HYDROXY-5-((p-SULPHOPHEN T,)AZO)-2-NAPHTHALENESULPHONIC ACID, DISODIUM SALTseeFAGlSO... 

From /8-naphthol-a-monosulphonic acid [48] and o-diazo-naphthalenesulphonic acid. Is a beautiful scarlet dyestuff which dissolves in sulphuric acid with a reddish-violet colour. 

TABLE 4. Heats of formation of two naphthalenesulphonic acids and their ammonium ion salts (all data are in kcal mol-1 and are from Reference 21)... 

Fluorescence polarization studies have also provided valuable information on excimer formation, energy migration, and molecular mobility in polymers. The role of hydrophobicity was analysed for mixtures of poly(methacrylic acid) and poly(A-vinyl-2-pyrrolidone) in solution, and the motion of 8-anilino-l-naphthalenesulphonic acid covalently bound to poly(methacrylic acid) has been... 

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