Sulphobenzoic acid

Saccharin (imide of o-sulphobenzoic acid). Upon oxidising o toluene-sulphonamide with potassium permanganate in alkaline solution, the sodium salt of o-sulphonamidobenzoic acid is formed, which upon acidifying with concentrated hydrochloric acid or warming passes spontaneously into the cyclic imide of o-sulphobenzoic acid or saccharin ... 

Derivatisation Quantification of carboxyl and hydroxyl groups with 2-(bromoniethyl)naphthalene and sulphobenzoic acid anhydride, respectively PET [11, 14]... 

Amino-2-sulphobenzoic acid [527-76-4] NI 217.1. Crystd from water. 

Nitro-4-sulphobenzoic acid [552-23-8] M 247.1, m 111°. Crystd from dilute HCl. 

Sulphobenzoic acid (monoammonium salt) [6939-89-5] M 219.5. Crystd from water. 

Amino-S-snlphanilylthiazole [473-30-3] M 238.3, m 219-221°(dec). Crystd from EtOH. 4-Amino-2-sulphobenzoic acid [527-76-4] M 217.1. Crystd from water. 

Sulphapyridine, 1007, 1008 Sulphides, 496, 497, 498, 500, 1078 Sulphinic acids, 826, 1078 o-Sulphobenzoic acid, acid ammonium salt, 988... 

Saccharin is soluble at 20°, in 290 parts of water, in 30 parts of alcohol, in 12 parts of acetone, in 50 parts of glycerol, in about 25 parts of boiling water. It is very slightly soluble in ether and chloroform soluble in dilute ammonia solution, and in solutions of alkali bicarbonates with evolution of carbon dioxide (9). Its aqueous solution is acid to litmus (2). On alkaline and acid hydrolysis saccharin gives rise to 0-sulphamoyl-benzoic acid and ammonium 0-sulphobenzoic acid respectively (2). 

Gomall and R. Robinson [28] suggested reducing sodium dinitrotoluene sulphate (e.g. the sodium salt of 2,4-dinitrotoluene-3-sulphonic acid) to yield m- toluene-diamine-3-sulphonic acid which could serve as an intermediate for obtaining azo dyes. Oxidation of sodium 2,4-dinitrotoluene-3-sulphonic acid with potassium permanganate in alkaline medium gave 2,4-dinitro-3-sulphobenzoic acid, also an intermediate for azo dyes. 

Toluene.—According to Renard,1 this compound, by electrolytic oxidation in alcoholic-sulphuric acid, forms benzaldehyde and phenose, C6H6(OH)6( ). According to Puls,2 there are produced in the same electrolyte, using a diaphragm and a platinum anode, benzaldehyde, benzoic acid, benzoic ethyl ester, and, as chief product, p-sulphobenzoic acid. Under the same conditions, Merzbacher and Smith3 had obtained a poor yield of benzoic ethyl ester. 

Sulphobenzoic Acid.—This acid, according to the statements of the same investigator, is not changed by the current. 

Interesting is the development of IPC-indirect photometric LC for UV-transparent ions, using a UV-absorbing counter ion such as sulphosalicylic or m-sulphobenzoic acid or potassium biphthalate197. 

The presence of a benzene ring in these acids makes it possible to prepare from them many derivatives which are characteristic of aromatic compounds. Benzoic acid is converted into nitrobenzoic acid by nitric acid and into sulphobenzoic acid by sulphuric acid. 

Sulphobenzoic Acids, HO3S.C6H4.COOH.—m-Sulpho-... 

Like phthalic acid, C6H4(COOH)2, o-sulphobenzoic acid yields an anhydride and an imide —... 

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