Sodium anthraquinone-2-sulfonate

Sodium anthraquinone-2-sulfonate (H2O) [131-08-8] M 328.3. See 9,10-anthraquinone-2-sulfonic acid disodium salt on p. 395. 

Alizarin (1,2-dihydroxyanthraquinone) is formed by alkali fusion of sodium anthraquinone-2-sulfonate ( silver salt ). The reaction is rather remarkable in that not only is the sulfo group replaced by hydroxyl, but a second hydroxyl is also introduced. The presence of an oxidizing agent has a favorable effect on the reaction. 

The mother liquor from the 1,8-disulfonic acid contains about 30 per cent of the original anthraquinone in the form of a complicated mixture of disulfonic acids (mainly the 1,7 acid along with a small amount of the 1,6 isomer, still smaller amounts of the 1,5 and 1,8 acids, and traces of the 2,6 and 2,7 compounds). This mixture cannot be separated in any simple way. In the industry, the residue is worked up to produce "silver salt by prolonged heating of the diluted sulfuric acid solution at 180-200°. This treatment splits out sulfo groups in the 1 position, and the resulting mixture of anthraquinone and anthraquinone-2-sulfonic acid is treated in the manner described under the preparation of sodium anthraquinone-2-sulfonate (page 228). 

Three additional solutions are also prepared. The first was a glucose solution containing 50% solids, prepared using 1443.4 g dextrose monohydrate and 1181 g water, thus containing 7.92 mol of glucose. The second was a 50% NaOH solution consisting of 840 g NaOH and 840 g water. The third was sodium anthraquinone 2-sulfonate (24 g) dissolved in 110 volumes of 30% H2O2. 

Sodium anthraquinone 2-sulfonate (SAM) is the reaction indicator. In the oxidized form it causes the solution to become deep red it is colorless in the reduced state. 

A novel clothing detergent was obtained when glucose syrup was oxidized in tandem by sodium anthraquinone 2-sulfonate/H202 and then NaOCl/TEMPO and is described (2). 

A solution of 2 g of sodium anthraquinone-2-sulfonate and 15 g of sodium hydrosulfite in 100 mL of a 20% aqueous solution of potassium hydroxide affords a blood-red solution of the diradical dianion ... 

Nitrogen [7727-37-9] M 28.0, b -195.8 . Cylinder N2 can be freed from oxygen by passage through Fieser s solution [which comprises 2g sodium anthraquinone-2-sulfonate and 15g sodium hydrosulfite dissolved in lOOmL of 20% KOH see Fieser, 7 Am Chem Soc 46 2639 7924] followed by scrubbing with saturated lead acetate solution (to remove any H2S generated by the Fieser solution), cone H2SO4 (to remove moisture), then... 

A number of important technical and economic considerations are involved in the use of sodium anthraquinone-2-sulfonate (silver salt) for the preparation of 2-Bminoanthraquinone. The cost of chloroanthra-quinone is approximately the same as anthraquinone when they are prepared according to the Friedel-Crafts reaction. The former lends itself to the direct production of an amine of 97-98.5 per cent purity. The product from silver salt is, however, of a higher purity and can, furthermore, be prepared at a lower operating temperature (viz., 170-180 C) so that steam-jacketed equipment can be employed. Consequently, despite economic handicaps, the silver-salt process is firmly entrenched and is used to a considerable extent. 

FIGURE 9.3 Structures of benzene, naphthalene, and anthracene derivatives analyzed sodium benzenesulfonate (1), 4-chloroaniline (2), 3,4-dichloroaniline (3), 2-naphthylamine (4), sodium 2-naphthalenesulfonate (5), sodium anthraquinone 2-sulfonate monohydrate (6), 1,2-diamineanthraquinone (7), 2-anthraceencarboxilic acid (8), and 2-anthramine (9). 

Anthraquinone-2-sodium sulfonate 2-Anthraquinonesulfonate sodium Anthraquinone-2-sulfonate sodium salt 2-Anthraquinone sulfonic acid, sodium salt Anthraquinone-p-sulfonic acid sodium salt. 

Empiricai CsHgNaOsS Properties M.w. 240.20 Uses Electroplating brightening agent Sodium 2-anthraquinone sulfonate CAS 131-08-8 EINECS/ELINCS 205-009-5 Synonyms 2-Anthracenesulfonic acid, 9,10-dihydro-9,10-dioxo-, sodium salt 9,10-Anthraquinone-2-sodium sulfonate 2-Anthraquinonesulfonate sodium Anthraquinone-2-sulfonate sodium salt 2-Anthraquinone sulfonic acid, sodium salt Anthraquinone-p-sulfonic acid sodium salt ... 

Reagents. Calix[4]resorcinarene (1) was prepared by a reported procedure (5). Closs-linkers, BHP and MBHP (8) were prepared by the reaction of phenol with formaldehyde in water. Photo acid generator, DIAS was prepared by the reaction of diphenyliodonium chloride with sodium 9,10-dimethoxyanthracene-2-sulfonate, which was obtained by the reduction of sodium anthraquinone-2-sulfonate with zinc and aqueous sodium hydroxide solution, followed by the methylation with dimethyl sulfate (9). 3,5-Dihydroxybenzoic acid (Merck) and 18-crown-6 (Tokyo Kasei Co.) were commercially available and used... 

It evolves no gases, but absorption is slower than in an alkaline pyrogallol solution. It can be accelerated by the addition of sodium anthraquinone-2-sulfonate or indigo carmine. 

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