Naphthalenetrisulfonic acids

In the manufacture of 2-naphthalenol, 2-naphthalenesulfonic acid must be converted to its sodium salt this can be done by adding sodium chloride to the acid, and by neutralizing with aqueous sodium hydroxide or neutralizing with the sodium sulfite by-product obtained in the caustic fusion of the sulfonate. The cmde sulfonation product, without isolation or purification of 2-naphthalenesulfonic acid, is used to make 1,6-, 2,6-, and 2,7-naphthalenedisulfonic acids and 1,3,6-naphthalenetrisulfonic acid by further sulfonation. By nitration, 5- and 8-nitro-2-naphthalenesulfonic acids, [89-69-1] and [117-41-9] respectively, are obtained, which are intermediates for Cleve s acid. All are dye intermediates. The cmde sulfonation product can be condensed with formaldehyde or alcohols or olefins to make valuable wetting, dispersing, and tanning agents. 

Another example of manufacture in this series is the sulfonation of an aminonaphthalenesulfonic acid, followed by selected desulfonation, to make 6-amino-l,3-naphthalenedisulfonic acid (21). Thus, 2-amino-l-naphthalenesulfonic acid made by amination of 2-hydroxy-1-naphthalenesulfonic acid is added to 20 wt % oleum at ca 35°C. At this temperature, 65 wt % oleum is added and the charge is stirred for 2 h, is then slowly heated to 100°C and is maintained for 12 h to produce 6-amino-l,3,5-naphthalenetrisulfonic acid. The mass is diluted with water and maintained for 3 h at 105°C to remove the sulfo group adjacent to the amino group. After cooling to ca 20°C and filtration, 6-amino-l,3-naphthalenedisulfonic acid is obtained in 80% yield (55). 

By the aLkaU fusion or alkaline hydrolysis under pressure of the appropriate naphthalenedisulfonic or naphthalenetrisulfonic acid or hydroxynaphthalenedisulfonic acid. 

By alkali fusion or alkaline hydrolysis under pressure of appropriate naphthalenedisulfonic or naphthalenetrisulfonic acid or hydroxynaphthalenedisulfonic acid f By alkaline hydrolysis of sulfone formed on boiling aqueous solution of diazonjum salt of S-arnino-l-naphthalenesulfonic acid or appropriate derivatives. 

Rivera-Utrifia and Sanchez-Polo [60] mentioned a fast degradation of 1,3, 6-naphthalenetrisulfonic acid at low pH (about 2.3) by a large number of activated carbons in contact with ozone. The catalytic activities of activated carbon quantified by the ash constituents are shown to give highly oxidative species in solution. 

Naphthalenetrisulfonic acid, 8,8 -(carbonylbis(imino-3,1-phenylenecarbonylimino(4-methyl-3,1-phenylene)carbonylimino))bis-, hexasodium salt NF060 NSC 34936 SK 24728 Sodium suramin Suramin Hexasodium Suramin sodium Suramina sodica Suramine sodique Suramine sodium Suraminum natricum sym-T-urea sodium salt. Veterinary preparation for the control of trypanosomiasis of domestic animals. Solid Soluble in H2O, insoluble in organic solvents LDso (mus iv) = 620 mg/kg. Bayer AG. 

Naphthalene-di- and/or -tri-sulfonic acids are obtained when oleum reacts with naphthalene at elevated temperatures and for an extended time directions for the preparation of 1,5-, 1,6-,146 and 2,7-naphthalenedisulfonic acid147 and of 1,3,5- and 1,3,6-naphthalenetrisulfonic acid are given in Fierz-David and Blangey s book.124a... 

---