Benzenesulfonate

This is a rare transformation. The reaction of 5-phenethylamine and the bis-sulfonyl chloride of 1,2-benzenesulfonic acid, followed by KNO2 and 18-crown-6 gave R-phenethyl alcohol in 70% yield and 40% enantiomeric excess (ee). ... 

Sulfonation Treatment of benzene with hot concentrated sulfuric acid gives benzenesulfonic acid A sulfonic acid group (—SO2OH) replaces one of the ring hydrogens... 

Step 3 A rapid proton transfer from the oxygen of sulfuric acid to the oxygen of benzenesulfonate completes the process... 

Nearly all commercial acetylations are realized using acid catalysts. Catalytic acetylation of alcohols can be carried out using mineral acids, eg, perchloric acid [7601-90-3], phosphoric acid [7664-38-2], sulfuric acid [7664-93-9], benzenesulfonic acid [98-11-3], or methanesulfonic acid [75-75-2], as the catalyst. Certain acid-reacting ion-exchange resins may also be used, but these tend to decompose in hot acetic acid. Mordenite [12445-20-4], a decationized Y-zeohte, is a useful acetylation catalyst (28) and aluminum chloride [7446-70-0], catalyzes / -butanol [71-36-3] acetylation (29). 

The second generation includes latices made with functional monomers like methacrylic acid, 2-hydroxyethyl acrylate [818-61 -17, acrylamide/75 -(9ti-/7, 2-dimethylaminoethylmethacrylate [2867-47-2] and sodiumT -vinyl-benzenesulfonate [98-70-4] that create in polymeric emulsifier. The initiator decomposition products, like the sulfate groups arising from persulfate decomposition, can also act as chemically bound surfactants. These surfactants are difficult to remove from the latex particle. 

Benzene SuIfona.tion. In the benzene sulfonation process, benzene reacts with concentrated sulfuric acid to form benzenesulfonic acid at about 150°C. The benzenesulfonic acid is neutralized with sodium sulfate to produce sodium benzenesulfonate, which is then fused with caustic soda to yield sodium phenate. The sodium phenate is acidified with sulfur dioxide and a small amount of sulfuric acid to release the phenol from the sodium salt. The phenol yield by this process can be as high as 88 mol % to that of the theoretical value based on benzene. Plants employing this technology have been shut down for environmental and economic reasons. 

In the presence of an anionic surfactant such as sodium dodecyl-benzenesulfonate [25155-30-0] any protonated amine salt present forms an insoluble salt (4). Salt formation results in an increase in the pH of the solution. 

A Methylamino)phenol. This derivative (15) is easily soluble ia ethyl acetate, ethanol, diethyl ether, and benzene. It is also soluble ia hot water, but only spatingly soluble ia cold water. Industrial synthesis is by heating 3-(A/-methylamino)benzenesulfonic acid with sodium hydroxide at 200—220°C (179) or by the reaction of resorciaol with methylamiae ia the presence of aqueous phosphoric acid at 200°C (180). 

A A Diethylamino)phenol. This derivative (16) forms rhombic bipyramidal crystals. Industrial synthesis is analogous to the previously described synthesis of 3-(/V,/V-dimethy1amino)pheno1 from resorciaol and diethylamiae, by reaction of 3-(Ai,A/-diethylamiQo)benzenesulfonic acid with sodium hydroxide, or by alkylation of 3-amiaophenol hydrochloride with ethanol. 

Economically, the most important acid red is Acid Red 151. This disazo dye (39) is obtained by coupling -aminophenylazo)benzenesulfonic acid to 2-naphthol. 

Sulfonation. Benzene is converted iato benzenesulfonic acid [98-11-3] C H SO, upon reaction with fuming sulfuric acid (oleum) or chlorosulfonic acid. y -Benzenedisulfonic acid [98-48-6] CgHgS20, is prepared by reaction of benzene-sulfonic acid with oleum for 8 h at 85°C. Often under these conditions, appreciable quantities ofT -benzenedisulfonic acid [31375-02-7] are produced. 1,3,5-Benzenetrisulfonic acid [617-99-2] C H S Og, is produced by heating the disulfonic acid with oleum at 230°C (21). 

In laboratory preparations, sulfuric acid and hydrochloric acid have classically been used as esterification catalysts. However, formation of alkyl chlorides or dehydration, isomerization, or polymerization side reactions may result. Sulfonic acids, such as benzenesulfonic acid, toluenesulfonic acid, or methanesulfonic acid, are widely used in plant operations because of their less corrosive nature. Phosphoric acid is sometimes employed, but it leads to rather slow reactions. Soluble or supported metal salts minimize side reactions but usually require higher temperatures than strong acids. 

Thiophene-2-sulfonic acid is a strong acid, similar to benzenesulfonic acid. It forms a sulfonyl chloride with phosphoryl chloride which on reduction with zinc yields thiophene-2-sulfinic acid. 

Addition-elimination reactions occur on treatment of 2,3-diphenylthiirene 1,1-dioxide with benzenesulfonate ion or with trisubstituted phosphines (Scheme 86) (75JQC3189). 

The lower limit of detection is 1 p.g/dm for sodium hexadecyl sulfonate, 2.5 p.g/dm for sodium dodecyl benzenesulfonate and 10 p.g/diW for sodium dodecyl sulfonate with sample volume of O.ldiW. The method proposed is highly sensitive, simple, rapid and guarantees environmental safety of analysis. 

Trimethylphenylammonium benzenesulfonate [16093-66-6] M 293.3. Crystd repeatedly from MeOH (charcoal). 

Benzyl Orange [4-(4-benzylaminophenylazo)benzenesulfonic acid potassium salt] [589-02-6] M 405.5, pKEst(i) <0, pKEst(2) 3.8. Crystd from H2O. 

Metanil Yellow (3[ 4-phenylamino phenylazo]-benzenesulfonic acid) [587-98-4] M 375.4, pKes, <0. Salted out from water three times with sodium acetate, then repeatedly extracted with EtOH [McGrew and Schneider, J Am Chem Soc 72 2547 7950]. 

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